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Apache CXF Development Guide

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Red Hat Fuse 7.8

Develop applications with Apache CXF Web services

Red Hat Fuse Documentation Team

Abstract

Guide to developing Web services using Apache CXF.

Part I. Writing WSDL Contracts

This part describes how to define a Web service interface using WSDL.

Chapter 1. Introducing WSDL Contracts

Abstract

WSDL documents define services using Web Service Description Language and a number of possible extensions. The documents have a logical part and a concrete part. The abstract part of the contract defines the service in terms of implementation neutral data types and messages. The concrete part of the document defines how an endpoint implementing a service will interact with the outside world.

The recommended approach to design services is to define your services in WSDL and XML Schema before writing any code. When hand-editing WSDL documents you must make sure that the document is valid, as well as correct. To do this you must have some familiarity with WSDL. You can find the standard on the W3C web site, www.w3.org.

1.1. Structure of a WSDL document

Overview

A WSDL document is, at its simplest, a collection of elements contained within a root definition element. These elements describe a service and how an endpoint implementing that service is accessed.

A WSDL document has two distinct parts:

  • A logical part that defines the service in implementation neutral terms
  • A concrete part that defines how an endpoint implementing the service is exposed on a network

The logical part

The logical part of a WSDL document contains the types, the message, and the portType elements. It describes the service’s interface and the messages exchanged by the service. Within the types element, XML Schema is used to define the structure of the data that makes up the messages. A number of message elements are used to define the structure of the messages used by the service. The portType element contains one or more operation elements that define the messages sent by the operations exposed by the service.

The concrete part

The concrete part of a WSDL document contains the binding and the service elements. It describes how an endpoint that implements the service connects to the outside world. The binding elements describe how the data units described by the message elements are mapped into a concrete, on-the-wire data format, such as SOAP. The service elements contain one or more port elements which define the endpoints implementing the service.

1.2. WSDL elements

A WSDL document is made up of the following elements:

  • definitions — The root element of a WSDL document. The attributes of this element specify the name of the WSDL document, the document’s target namespace, and the shorthand definitions for the namespaces referenced in the WSDL document.
  • types — The XML Schema definitions for the data units that form the building blocks of the messages used by a service. For information about defining data types see Chapter 2, Defining Logical Data Units.
  • message — The description of the messages exchanged during invocation of a services operations. These elements define the arguments of the operations making up your service. For information on defining messages see Chapter 3, Defining Logical Messages Used by a Service.
  • portType — A collection of operation elements describing the logical interface of a service. For information about defining port types see Chapter 4, Defining Your Logical Interfaces.
  • operation — The description of an action performed by a service. Operations are defined by the messages passed between two endpoints when the operation is invoked. For information on defining operations see the section called “Operations”.
  • binding — The concrete data format specification for an endpoint. A binding element defines how the abstract messages are mapped into the concrete data format used by an endpoint. This element is where specifics such as parameter order and return values are specified.
  • service — A collection of related port elements. These elements are repositories for organizing endpoint definitions.
  • port — The endpoint defined by a binding and a physical address. These elements bring all of the abstract definitions together, combined with the definition of transport details, and they define the physical endpoint on which a service is exposed.

1.3. Designing a contract

To design a WSDL contract for your services you must perform the following steps:

  1. Define the data types used by your services.
  2. Define the messages used by your services.
  3. Define the interfaces for your services.
  4. Define the bindings between the messages used by each interface and the concrete representation of the data on the wire.
  5. Define the transport details for each of the services.

Chapter 2. Defining Logical Data Units

Abstract

When describing a service in a WSDL contract complex data types are defined as logical units using XML Schema.

2.1. Introduction to Logical Data Units

When defining a service, the first thing you must consider is how the data used as parameters for the exposed operations is going to be represented. Unlike applications that are written in a programming language that uses fixed data structures, services must define their data in logical units that can be consumed by any number of applications. This involves two steps:

  1. Breaking the data into logical units that can be mapped into the data types used by the physical implementations of the service
  2. Combining the logical units into messages that are passed between endpoints to carry out the operations

This chapter discusses the first step. Chapter 3, Defining Logical Messages Used by a Service discusses the second step.

2.2. Mapping data into logical data units

Overview

The interfaces used to implement a service define the data representing operation parameters as XML documents. If you are defining an interface for a service that is already implemented, you must translate the data types of the implemented operations into discreet XML elements that can be assembled into messages. If you are starting from scratch, you must determine the building blocks from which your messages are built, so that they make sense from an implementation standpoint.

Available type systems for defining service data units

According to the WSDL specification, you can use any type system you choose to define data types in a WSDL contract. However, the W3C specification states that XML Schema is the preferred canonical type system for a WSDL document. Therefore, XML Schema is the intrinsic type system in Apache CXF.

XML Schema as a type system

XML Schema is used to define how an XML document is structured. This is done by defining the elements that make up the document. These elements can use native XML Schema types, like xsd:int, or they can use types that are defined by the user. User defined types are either built up using combinations of XML elements or they are defined by restricting existing types. By combining type definitions and element definitions you can create intricate XML documents that can contain complex data.

When used in WSDL XML Schema defines the structure of the XML document that holds the data used to interact with a service. When defining the data units used by your service, you can define them as types that specify the structure of the message parts. You can also define your data units as elements that make up the message parts.

Considerations for creating your data units

You might consider simply creating logical data units that map directly to the types you envision using when implementing the service. While this approach works, and closely follows the model of building RPC-style applications, it is not necessarily ideal for building a piece of a service-oriented architecture.

The Web Services Interoperability Organization’s WS-I basic profile provides a number of guidelines for defining data units and can be accessed at http://www.ws-i.org/Profiles/BasicProfile-1.1-2004-08-24.html#WSDLTYPES. In addition, the W3C also provides the following guidelines for using XML Schema to represent data types in WSDL documents:

  • Use elements, not attributes.
  • Do not use protocol-specific types as base types.

2.3. Adding data units to a contract

Overview

Depending on how you choose to create your WSDL contract, creating new data definitions requires varying amounts of knowledge. The Apache CXF GUI tools provide a number of aids for describing data types using XML Schema. Other XML editors offer different levels of assistance. Regardless of the editor you choose, it is a good idea to have some knowledge about what the resulting contract should look like.

Procedure

Defining the data used in a WSDL contract involves the following steps:

  1. Determine all the data units used in the interface described by the contract.
  2. Create a types element in your contract.
  3. Create a schema element, shown in Example 2.1, “Schema entry for a WSDL contract”, as a child of the type element.

    The targetNamespace attribute specifies the namespace under which new data types are defined. Best practice is to also define the namespace that provides access to the target namespace. The remaining entries should not be changed.

    Example 2.1. Schema entry for a WSDL contract

    <schema targetNamespace="http://schemas.iona.com/bank.idl"
            xmlns="http://www.w3.org/2001/XMLSchema"
            xmlns:xsd1="http://schemas.iona.com/bank.idl"
            xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/">
  4. For each complex type that is a collection of elements, define the data type using a complexType element. See Section 2.5.1, “Defining data structures”.
  5. For each array, define the data type using a complexType element. See Section 2.5.2, “Defining arrays”.
  6. For each complex type that is derived from a simple type, define the data type using a simpleType element. See Section 2.5.4, “Defining types by restriction”.
  7. For each enumerated type, define the data type using a simpleType element. See Section 2.5.5, “Defining enumerated types”.
  8. For each element, define it using an element element. See Section 2.6, “Defining elements”.

2.4. XML Schema simple types

Overview

If a message part is going to be of a simple type it is not necessary to create a type definition for it. However, the complex types used by the interfaces defined in the contract are defined using simple types.

Entering simple types

XML Schema simple types are mainly placed in the element elements used in the types section of your contract. They are also used in the base attribute of restriction elements and extension elements.

Simple types are always entered using the xsd prefix. For example, to specify that an element is of type int, you would enter xsd:int in its type attribute as shown in Example 2.2, “Defining an element with a simple type”.

Example 2.2. Defining an element with a simple type

<element name="simpleInt" type="xsd:int" />

Supported XSD simple types

Apache CXF supports the following XML Schema simple types:

  • xsd:string
  • xsd:normalizedString
  • xsd:int
  • xsd:unsignedInt
  • xsd:long
  • xsd:unsignedLong
  • xsd:short
  • xsd:unsignedShort
  • xsd:float
  • xsd:double
  • xsd:boolean
  • xsd:byte
  • xsd:unsignedByte
  • xsd:integer
  • xsd:positiveInteger
  • xsd:negativeInteger
  • xsd:nonPositiveInteger
  • xsd:nonNegativeInteger
  • xsd:decimal
  • xsd:dateTime
  • xsd:time
  • xsd:date
  • xsd:QName
  • xsd:base64Binary
  • xsd:hexBinary
  • xsd:ID
  • xsd:token
  • xsd:language
  • xsd:Name
  • xsd:NCName
  • xsd:NMTOKEN
  • xsd:anySimpleType
  • xsd:anyURI
  • xsd:gYear
  • xsd:gMonth
  • xsd:gDay
  • xsd:gYearMonth
  • xsd:gMonthDay

2.5. Defining complex data types

Abstract

XML Schema provides a flexible and powerful mechanism for building complex data structures from its simple data types. You can create data structures by creating a sequence of elements and attributes. You can also extend your defined types to create even more complex types.

In addition to building complex data structures, you can also describe specialized types such as enumerated types, data types that have a specific range of values, or data types that need to follow certain patterns by either extending or restricting the primitive types.

2.5.1. Defining data structures

Overview

In XML Schema, data units that are a collection of data fields are defined using complexType elements. Specifying a complex type requires three pieces of information:

  1. The name of the defined type is specified in the name attribute of the complexType element.
  2. The first child element of the complexType describes the behavior of the structure’s fields when it is put on the wire. See the section called “Complex type varieties”.
  3. Each of the fields of the defined structure are defined in element elements that are grandchildren of the complexType element. See the section called “Defining the parts of a structure”.

For example, the structure shown in Example 2.3, “Simple Structure” is defined in XML Schema as a complex type with two elements.

Example 2.3. Simple Structure

struct personalInfo
{
  string name;
  int age;
};

Example 2.4, “A complex type” shows one possible XML Schema mapping for the structure shown in Example 2.3, “Simple Structure” The structure defined in Example 2.4, “A complex type” generates a message containing two elements: name and age.

.

Example 2.4. A complex type

<complexType name="personalInfo">
  <sequence>
    <element name="name" type="xsd:string" />
    <element name="age" type="xsd:int" />
  </sequence>
</complexType>
Complex type varieties

XML Schema has three ways of describing how the fields of a complex type are organized when represented as an XML document and passed on the wire. The first child element of the complexType element determines which variety of complex type is being used. Table 2.1, “Complex type descriptor elements” shows the elements used to define complex type behavior.

Table 2.1. Complex type descriptor elements
ElementComplex Type Behavior

sequence

All of a complex type’s fields can be present and they must be in the order in which they are specified in the type definition.

all

All of the complex type’s fields can be present but they can be in any order.

choice

Only one of the elements in the structure can be placed in the message.

If the structure is defined using a choice element, as shown in Example 2.5, “Simple complex choice type”, it generates a message with either a name element or an age element.

Example 2.5. Simple complex choice type

<complexType name="personalInfo">
  <choice>
    <element name="name" type="xsd:string"/>
    <element name="age" type="xsd:int"/>
  </choice>
</complexType>
Defining the parts of a structure

You define the data fields that make up a structure using element elements. Every complexType element should contain at least one element element. Each element element in the complexType element represents a field in the defined data structure.

To fully describe a field in a data structure, element elements have two required attributes:

  • The name attribute specifies the name of the data field and it must be unique within the defined complex type.
  • The type attribute specifies the type of the data stored in the field. The type can be either one of the XML Schema simple types, or any named complex type that is defined in the contract.

In addition to name and type, element elements have two other commonly used optional attributes: minOcurrs and maxOccurs. These attributes place bounds on the number of times the field occurs in the structure. By default, each field occurs only once in a complex type. Using these attributes, you can change how many times a field must or can appear in a structure. For example, you can define a field, previousJobs, that must occur at least three times, and no more than seven times, as shown in Example 2.6, “Simple complex type with occurrence constraints”.

Example 2.6. Simple complex type with occurrence constraints

<complexType name="personalInfo">
  <all>
    <element name="name" type="xsd:string"/>
    <element name="age" type="xsd:int"/>
    <element name="previousJobs" type="xsd:string:
             minOccurs="3" maxOccurs="7"/>
  </all>
</complexType>

You can also use the minOccurs to make the age field optional by setting the minOccurs to zero as shown in Example 2.7, “Simple complex type with minOccurs set to zero”. In this case age can be omitted and the data will still be valid.

Example 2.7. Simple complex type with minOccurs set to zero

<complexType name="personalInfo">
  <choice>
    <element name="name" type="xsd:string"/>
    <element name="age" type="xsd:int" minOccurs="0"/>
  </choice>
</complexType>
Defining attributes

In XML documents, attributes are contained in the element’s tag. For example, in the complexType element in the code below, name is an attribute. To specify an attribute for a complex type, you define an attribute element in the complexType element definition. An attribute element can appear only after the all, sequence, or choice element. Specify one attribute element for each of the complex type’s attributes. Any attribute elements must be direct children of the complexType element.

Example 2.8. Complex type with an attribute

<complexType name="personalInfo">
  <all>
    <element name="name" type="xsd:string"/>
    <element name="previousJobs" type="xsd:string"
             minOccurs="3" maxOccurs="7"/>
  </all>
  <attribute name="age" type="xsd:int" use="required" />
</complexType>

In the previous code, the attribute element specifies that the personalInfo complex type has an age attribute. The attribute element has these attributes:

  • name — A required attribute that specifies the string that identifies the attribute.
  • type — Specifies the type of the data stored in the field. The type can be one of the XML Schema simple types.
  • use — An optional attribute that specifies whether the complex type is required to have this attribute. Valid values are required or optional. The default is that the attribute is optional.

In an attribute element, you can specify the optional default attribute, which lets you specify a default value for the attribute.

2.5.2. Defining arrays

Overview

Apache CXF supports two methods for defining arrays in a contract. The first is define a complex type with a single element whose maxOccurs attribute has a value greater than one. The second is to use SOAP arrays. SOAP arrays provide added functionality such as the ability to easily define multi-dimensional arrays and to transmit sparsely populated arrays.

Complex type arrays

Complex type arrays are a special case of a sequence complex type. You simply define a complex type with a single element and specify a value for the maxOccurs attribute. For example, to define an array of twenty floating point numbers you use a complex type similar to the one shown in Example 2.9, “Complex type array”.

Example 2.9. Complex type array

<complexType name="personalInfo">
  <element name="averages" type="xsd:float" maxOccurs="20"/>
</complexType>

You can also specify a value for the minOccurs attribute.

SOAP arrays

SOAP arrays are defined by deriving from the SOAP-ENC:Array base type using the wsdl:arrayType element. The syntax for this is shown in Example 2.10, “Syntax for a SOAP array derived using wsdl:arrayType”. Ensure that the definitions element declares xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/".

Example 2.10. Syntax for a SOAP array derived using wsdl:arrayType

<complexType name="TypeName">
  <complexContent>
    <restriction base="SOAP-ENC:Array">
      <attribute ref="SOAP-ENC:arrayType"
                 wsdl:arrayType="ElementType<ArrayBounds>"/>
    </restriction>
  </complexContent>
</complexType>

Using this syntax, TypeName specifies the name of the newly-defined array type. ElementType specifies the type of the elements in the array. ArrayBounds specifies the number of dimensions in the array. To specify a single dimension array use []; to specify a two-dimensional array use either [][] or [,].

For example, the SOAP Array, SOAPStrings, shown in Example 2.11, “Definition of a SOAP array”, defines a one-dimensional array of strings. The wsdl:arrayType attribute specifies the type of the array elements, xsd:string, and the number of dimensions, with [] implying one dimension.

Example 2.11. Definition of a SOAP array

<complexType name="SOAPStrings">
  <complexContent>
    <restriction base="SOAP-ENC:Array">
      <attribute ref="SOAP-ENC:arrayType"
                 wsdl:arrayType="xsd:string[]"/>
    </restriction>
  </complexContent>
</complexType>

You can also describe a SOAP Array using a simple element as described in the SOAP 1.1 specification. The syntax for this is shown in Example 2.12, “Syntax for a SOAP array derived using an element”.

Example 2.12. Syntax for a SOAP array derived using an element

<complexType name="TypeName">
  <complexContent>
    <restriction base="SOAP-ENC:Array">
      <sequence>
        <element name="ElementName" type="ElementType"
                 maxOccurs="unbounded"/>
      </sequence>
    </restriction>
  </complexContent>
</complexType>

When using this syntax, the element’s maxOccurs attribute must always be set to unbounded.

2.5.3. Defining types by extension

Like most major coding languages, XML Schema allows you to create data types that inherit some of their elements from other data types. This is called defining a type by extension. For example, you could create a new type called alienInfo, that extends the personalInfo structure defined in Example 2.4, “A complex type” by adding a new element called planet.

Types defined by extension have four parts:

  1. The name of the type is defined by the name attribute of the complexType element.
  2. The complexContent element specifies that the new type will have more than one element.

    Note

    If you are only adding new attributes to the complex type, you can use a simpleContent element.

  3. The type from which the new type is derived, called the base type, is specified in the base attribute of the extension element.
  4. The new type’s elements and attributes are defined in the extension element, the same as they are for a regular complex type.

For example, alienInfo is defined as shown in Example 2.13, “Type defined by extension”.

Example 2.13. Type defined by extension

<complexType name="alienInfo">
  <complexContent>
    <extension base="xsd1:personalInfo">
      <sequence>
        <element name="planet" type="xsd:string"/>
      </sequence>
    </extension>
  </complexContent>
</complexType>

2.5.4. Defining types by restriction

Overview

XML Schema allows you to create new types by restricting the possible values of an XML Schema simple type. For example, you can define a simple type, SSN, which is a string of exactly nine characters. New types defined by restricting simple types are defined using a simpleType element.

The definition of a type by restriction requires three things:

  1. The name of the new type is specified by the name attribute of the simpleType element.
  2. The simple type from which the new type is derived, called the base type, is specified in the restriction element. See the section called “Specifying the base type”.
  3. The rules, called facets, defining the restrictions placed on the base type are defined as children of the restriction element. See the section called “Defining the restrictions”.
Specifying the base type

The base type is the type that is being restricted to define the new type. It is specified using a restriction element. The restriction element is the only child of a simpleType element and has one attribute, base, that specifies the base type. The base type can be any of the XML Schema simple types.

For example, to define a new type by restricting the values of an xsd:int you use a definition like the one shown in Example 2.14, “Using int as the base type”.

Example 2.14. Using int as the base type

<simpleType name="restrictedInt">
  <restriction base="xsd:int">
    ...
  </restriction>
</simpleType>
Defining the restrictions

The rules defining the restrictions placed on the base type are called facets. Facets are elements with one attribute, value, that defines how the facet is enforced. The available facets and their valid value settings depend on the base type. For example, xsd:string supports six facets, including:

  • length
  • minLength
  • maxLength
  • pattern
  • whitespace
  • enumeration

Each facet element is a child of the restriction element.

Example

Example 2.15, “SSN simple type description” shows an example of a simple type, SSN, which represents a social security number. The resulting type is a string of the form xxx-xx-xxxx. <SSN>032-43-9876<SSN> is a valid value for an element of this type, but <SSN>032439876</SSN> is not.

Example 2.15. SSN simple type description

<simpleType name="SSN">
  <restriction base="xsd:string">
    <pattern value="\d{3}-\d{2}-\d{4}"/>
  </restriction>
</simpleType>

2.5.5. Defining enumerated types

Overview

Enumerated types in XML Schema are a special case of definition by restriction. They are described by using the enumeration facet which is supported by all XML Schema primitive types. As with enumerated types in most modern programming languages, a variable of this type can only have one of the specified values.

Defining an enumeration in XML Schema

The syntax for defining an enumeration is shown in Example 2.16, “Syntax for an enumeration”.

Example 2.16. Syntax for an enumeration

<simpleType name="EnumName">
  <restriction base="EnumType">
    <enumeration value="Case1Value"/>
    <enumeration value="Case2Value"/>
    ...
    <enumeration value="CaseNValue"/>
  </restriction>
</simpleType>

EnumName specifies the name of the enumeration type. EnumType specifies the type of the case values. CaseNValue, where N is any number one or greater, specifies the value for each specific case of the enumeration. An enumerated type can have any number of case values, but because it is derived from a simple type, only one of the case values is valid at a time.

Example

For example, an XML document with an element defined by the enumeration widgetSize, shown in Example 2.17, “widgetSize enumeration”, would be valid if it contained <widgetSize>big</widgetSize>, but it would not be valid if it contained <widgetSize>big,mungo</widgetSize>.

Example 2.17. widgetSize enumeration

<simpleType name="widgetSize">
  <restriction base="xsd:string">
    <enumeration value="big"/>
    <enumeration value="large"/>
    <enumeration value="mungo"/>
  </restriction>
</simpleType>

2.6. Defining elements

Elements in XML Schema represent an instance of an element in an XML document generated from the schema. The most basic element consists of a single element element. Like the element element used to define the members of a complex type, they have three attributes:

  • name — A required attribute that specifies the name of the element as it appears in an XML document.
  • type — Specifies the type of the element. The type can be any XML Schema primitive type or any named complex type defined in the contract. This attribute can be omitted if the type has an in-line definition.
  • nillable — Specifies whether an element can be omitted from a document entirely. If nillable is set to true, the element can be omitted from any document generated using the schema.

An element can also have an in-line type definition. In-line types are specified using either a complexType element or a simpleType element. Once you specify if the type of data is complex or simple, you can define any type of data needed using the tools available for each type of data. In-line type definitions are discouraged because they are not reusable.

Chapter 3. Defining Logical Messages Used by a Service

Abstract

A service is defined by the messages exchanged when its operations are invoked. In a WSDL contract these messages are defined using message element. The messages are made up of one or more parts that are defined using part elements.

Overview

A service’s operations are defined by specifying the logical messages that are exchanged when an operation is invoked. These logical messages define the data that is passed over a network as an XML document. They contain all of the parameters that are a part of a method invocation. Logical messages are defined using the message element in your contracts. Each logical message consists of one or more parts, defined in part elements.

While your messages can list each parameter as a separate part, the recommended practice is to use only a single part that encapsulates the data needed for the operation.

Messages and parameter lists

Each operation exposed by a service can have only one input message and one output message. The input message defines all of the information the service receives when the operation is invoked. The output message defines all of the data that the service returns when the operation is completed. Fault messages define the data that the service returns when an error occurs.

In addition, each operation can have any number of fault messages. The fault messages define the data that is returned when the service encounters an error. These messages usually have only one part that provides enough information for the consumer to understand the error.

Message design for integrating with legacy systems

If you are defining an existing application as a service, you must ensure that each parameter used by the method implementing the operation is represented in a message. You must also ensure that the return value is included in the operation’s output message.

One approach to defining your messages is RPC style. When using RPC style, you define the messages using one part for each parameter in the method’s parameter list. Each message part is based on a type defined in the types element of the contract. Your input message contains one part for each input parameter in the method. Your output message contains one part for each output parameter, plus a part to represent the return value, if needed. If a parameter is both an input and an output parameter, it is listed as a part for both the input message and the output message.

RPC style message definition is useful when service enabling legacy systems that use transports such as Tibco or CORBA. These systems are designed around procedures and methods. As such, they are easiest to model using messages that resemble the parameter lists for the operation being invoked. RPC style also makes a cleaner mapping between the service and the application it is exposing.

Message design for SOAP services

While RPC style is useful for modeling existing systems, the service’s community strongly favors the wrapped document style. In wrapped document style, each message has a single part. The message’s part references a wrapper element defined in the types element of the contract. The wrapper element has the following characteristics:

  • It is a complex type containing a sequence of elements. For more information see Section 2.5, “Defining complex data types”.
  • If it is a wrapper for an input message:

    • It has one element for each of the method’s input parameters.
    • Its name is the same as the name of the operation with which it is associated.
  • If it is a wrapper for an output message:

    • It has one element for each of the method’s output parameters and one element for each of the method’s inout parameters.
    • Its first element represents the method’s return parameter.
    • Its name would be generated by appending Response to the name of the operation with which the wrapper is associated.

Message naming

Each message in a contract must have a unique name within its namespace. It is recommended that you use the following naming conventions:

  • Messages should only be used by a single operation.
  • Input message names are formed by appending Request to the name of the operation.
  • Output message names are formed by appending Response to the name of the operation.
  • Fault message names should represent the reason for the fault.

Message parts

Message parts are the formal data units of the logical message. Each part is defined using a part element, and is identified by a name attribute and either a type attribute or an element attribute that specifies its data type. The data type attributes are listed in Table 3.1, “Part data type attributes”.

Table 3.1. Part data type attributes
AttributeDescription

element="elem_name"

The data type of the part is defined by an element called elem_name.

type="type_name"

The data type of the part is defined by a type called type_name.

Messages are allowed to reuse part names. For instance, if a method has a parameter, foo, that is passed by reference or is an in/out, it can be a part in both the request message and the response message, as shown in Example 3.1, “Reused part”.

Example 3.1. Reused part

<message name="fooRequest">
  <part name="foo" type="xsd:int"/>
<message>
<message name="fooReply">
  <part name="foo" type="xsd:int"/>
<message>

Example

For example, imagine you had a server that stored personal information and provided a method that returned an employee’s data based on the employee’s ID number. The method signature for looking up the data is similar to Example 3.2, “personalInfo lookup method”.

Example 3.2. personalInfo lookup method

personalInfo lookup(long empId)

This method signature can be mapped to the RPC style WSDL fragment shown in Example 3.3, “RPC WSDL message definitions”.

Example 3.3. RPC WSDL message definitions

<message name="personalLookupRequest">
  <part name="empId" type="xsd:int"/>
<message/>
<message name="personalLookupResponse>
  <part name="return" element="xsd1:personalInfo"/>
<message/>

It can also be mapped to the wrapped document style WSDL fragment shown in Example 3.4, “Wrapped document WSDL message definitions”.

Example 3.4. Wrapped document WSDL message definitions

<wsdl:types>
  <xsd:schema ... >
  ...
  <element name="personalLookup">
    <complexType>
      <sequence>
        <element name="empID" type="xsd:int" />
      </sequence>
    </complexType>
  </element>
  <element name="personalLookupResponse">
    <complexType>
      <sequence>
        <element name="return" type="personalInfo" />
      </sequence>
    </complexType>
  </element>
  </schema>
</types>
<wsdl:message name="personalLookupRequest">
  <wsdl:part name="empId" element="xsd1:personalLookup"/>
<message/>
<wsdl:message name="personalLookupResponse">
  <wsdl:part name="return" element="xsd1:personalLookupResponse"/>
<message/>

Chapter 4. Defining Your Logical Interfaces

Abstract

Logical service interfaces are defined using the portType element.

Overview

Logical service interfaces are defined using the WSDL portType element. The portType element is a collection of abstract operation definitions. Each operation is defined by the input, output, and fault messages used to complete the transaction the operation represents. When code is generated to implement the service interface defined by a portType element, each operation is converted into a method containing the parameters defined by the input, output, and fault messages specified in the contract.

Process

To define a logical interface in a WSDL contract you must do the following:

  1. Create a portType element to contain the interface definition and give it a unique name. See the section called “Port types”.
  2. Create an operation element for each operation defined in the interface. See the section called “Operations”.
  3. For each operation, specify the messages used to represent the operation’s parameter list, return type, and exceptions. See the section called “Operation messages”.

Port types

A WSDL portType element is the root element in a logical interface definition. While many Web service implementations map portType elements directly to generated implementation objects, a logical interface definition does not specify the exact functionality provided by the the implemented service. For example, a logical interface named ticketSystem can result in an implementation that either sells concert tickets or issues parking tickets.

The portType element is the unit of a WSDL document that is mapped into a binding to define the physical data used by an endpoint exposing the defined service.

Each portType element in a WSDL document must have a unique name, which is specified using the name attribute, and is made up of a collection of operations, which are described in operation elements. A WSDL document can describe any number of port types.

Operations

Logical operations, defined using WSDL operation elements, define the interaction between two endpoints. For example, a request for a checking account balance and an order for a gross of widgets can both be defined as operations.

Each operation defined within a portType element must have a unique name, specified using the name attribute. The name attribute is required to define an operation.

Operation messages

Logical operations are made up of a set of elements representing the logical messages communicated between the endpoints to execute the operation. The elements that can describe an operation are listed in Table 4.1, “Operation message elements”.

Table 4.1. Operation message elements
ElementDescription

input

Specifies the message the client endpoint sends to the service provider when a request is made. The parts of this message correspond to the input parameters of the operation.

output

Specifies the message that the service provider sends to the client endpoint in response to a request. The parts of this message correspond to any operation parameters that can be changed by the service provider, such as values passed by reference. This includes the return value of the operation.

fault

Specifies a message used to communicate an error condition between the endpoints.

An operation is required to have at least one input or one output element. An operation can have both input and output elements, but it can only have one of each. Operations are not required to have any fault elements, but can, if required, have any number of fault elements.

The elements have the two attributes listed in Table 4.2, “Attributes of the input and output elements”.

Table 4.2. Attributes of the input and output elements
AttributeDescription

name

Identifies the message so it can be referenced when mapping the operation to a concrete data format. The name must be unique within the enclosing port type.

message

Specifies the abstract message that describes the data being sent or received. The value of the message attribute must correspond to the name attribute of one of the abstract messages defined in the WSDL document.

It is not necessary to specify the name attribute for all input and output elements; WSDL provides a default naming scheme based on the enclosing operation’s name. If only one element is used in the operation, the element name defaults to the name of the operation. If both an input and an output element are used, the element name defaults to the name of the operation with either Request or Response respectively appended to the name.

Return values

Because the operation element is an abstract definition of the data passed during an operation, WSDL does not provide for return values to be specified for an operation. If a method returns a value it will be mapped into the output element as the last part of that message.

Example

For example, you might have an interface similar to the one shown in Example 4.1, “personalInfo lookup interface”.

Example 4.1. personalInfo lookup interface

interface personalInfoLookup
{
  personalInfo lookup(in int empID)
  raises(idNotFound);
}

This interface can be mapped to the port type in Example 4.2, “personalInfo lookup port type”.

Example 4.2. personalInfo lookup port type

<message name="personalLookupRequest">
  <part name="empId" element="xsd1:personalLookup"/>
<message/>
<message name="personalLookupResponse">
  <part name="return" element="xsd1:personalLookupResponse"/>
<message/>
<message name="idNotFoundException">
  <part name="exception" element="xsd1:idNotFound"/>
<message/>
<portType name="personalInfoLookup">
  <operation name="lookup">
    <input name="empID" message="tns:personalLookupRequest"/>
    <output name="return" message="tns:personalLookupResponse"/>
    <fault name="exception" message="tns:idNotFoundException"/>
  </operation>
</portType>

Part II. Web Services Bindings

This part describes how to add Apache CXF bindings to a WSDL document.

Chapter 5. Understanding Bindings in WSDL

Abstract

Bindings map the logical messages used to define a service into a concrete payload format that can be transmitted and received by an endpoint.

Overview

Bindings provide a bridge between the logical messages used by a service to a concrete data format that an endpoint uses in the physical world. They describe how the logical messages are mapped into a payload format that is used on the wire by an endpoint. It is within the bindings that details such as parameter order, concrete data types, and return values are specified. For example, the parts of a message can be reordered in a binding to reflect the order required by an RPC call. Depending on the binding type, you can also identify which of the message parts, if any, represent the return type of a method.

Port types and bindings

Port types and bindings are directly related. A port type is an abstract definition of a set of interactions between two logical services. A binding is a concrete definition of how the messages used to implement the logical services will be instantiated in the physical world. Each binding is then associated with a set of network details that finish the definition of one endpoint that exposes the logical service defined by the port type.

To ensure that an endpoint defines only a single service, WSDL requires that a binding can only represent a single port type. For example, if you had a contract with two port types, you could not write a single binding that mapped both of them into a concrete data format. You would need two bindings.

However, WSDL allows for a port type to be mapped to several bindings. For example, if your contract had a single port type, you could map it into two or more bindings. Each binding could alter how the parts of the message are mapped or they could specify entirely different payload formats for the message.

The WSDL elements

Bindings are defined in a contract using the WSDL binding element. The binding element consists of attributes like, name, that specifies a unique name for the binding and type that provides reference to PortType. The value of this attribute is used to associate the binding with an endpoint as discussed in Chapter 4, Defining Your Logical Interfaces.

The actual mappings are defined in the children of the binding element. These elements vary depending on the type of payload format you decide to use. The different payload formats and the elements used to specify their mappings are discussed in the following chapters.

Adding to a contract

Apache CXF provides command line tools that can generate bindings for predefined service interfaces.

The tools will add the proper elements to your contract for you. However, it is recommended that you have some knowledge of how the different types of bindings work.

You can also add a binding to a contract using any text editor. When hand editing a contract, you are responsible for ensuring that the contract is valid.

Supported bindings

Apache CXF supports the following bindings:

  • SOAP 1.1
  • SOAP 1.2
  • CORBA
  • Pure XML

Chapter 6. Using SOAP 1.1 Messages

Abstract

Apache CXF provides a tool to generate a SOAP 1.1 binding which does not use any SOAP headers. However, you can add SOAP headers to your binding using any text or XML editor.

6.1. Adding a SOAP 1.1 Binding

Using wsdl2soap

To generate a SOAP 1.1 binding using wsdl2soap use the following command: wsdl2soap-iport-type-name-bbinding-name-doutput-directory-ooutput-file-nsoap-body-namespace-style (document/rpc)-use (literal/encoded)-v-verbose-quietwsdlurl

Note

To use wsdl2soap you will need to download the Apache CXF distribution.

The command has the following options:

OptionInterpretation

-i port-type-name

Specifies the portType element for which a binding is generated.

wsdlurl

The path and name of the WSDL file containing the portType element definition.

The tool has the following optional arguments:

OptionInterpretation

-b binding-name

Specifies the name of the generated SOAP binding.

-d output-directory

Specifies the directory to place the generated WSDL file.

-o output-file

Specifies the name of the generated WSDL file.

-n soap-body-namespace

Specifies the SOAP body namespace when the style is RPC.

-style (document/rpc)

Specifies the encoding style (document or RPC) to use in the SOAP binding. The default is document.

-use (literal/encoded)

Specifies the binding use (encoded or literal) to use in the SOAP binding. The default is literal.

-v

Displays the version number for the tool.

-verbose

Displays comments during the code generation process.

-quiet

Suppresses comments during the code generation process.

The -iport-type-name and wsdlurl arguments are required. If the -style rpc argument is specified, the -nsoap-body-namspace argument is also required. All other arguments are optional and may be listed in any order.

Important

wsdl2soap does not support the generation of document/encoded SOAP bindings.

Example

If your system has an interface that takes orders and offers a single operation to process the orders it is defined in a WSDL fragment similar to the one shown in Example 6.1, “Ordering System Interface”.

Example 6.1. Ordering System Interface

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="widgetOrderForm.wsdl"
    targetNamespace="http://widgetVendor.com/widgetOrderForm"
    xmlns="http://schemas.xmlsoap.org/wsdl/"
    xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/"
    xmlns:tns="http://widgetVendor.com/widgetOrderForm"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:xsd1="http://widgetVendor.com/types/widgetTypes"
    xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">

<message name="widgetOrder">
  <part name="numOrdered" type="xsd:int"/>
</message>
<message name="widgetOrderBill">
  <part name="price" type="xsd:float"/>
</message>
<message name="badSize">
  <part name="numInventory" type="xsd:int"/>
</message>

<portType name="orderWidgets">
  <operation name="placeWidgetOrder">
    <input message="tns:widgetOrder" name="order"/>
    <output message="tns:widgetOrderBill" name="bill"/>
    <fault message="tns:badSize" name="sizeFault"/>
  </operation>
</portType>
...
</definitions>

The SOAP binding generated for orderWidgets is shown in Example 6.2, “SOAP 1.1 Binding for orderWidgets.

Example 6.2. SOAP 1.1 Binding for orderWidgets

<binding name="orderWidgetsBinding" type="tns:orderWidgets">
  <soap:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="placeWidgetOrder">
      <soap:operation soapAction="" style="document"/>
      <input name="order">
        <soap:body use="literal"/>
      </input>
      <output name="bill">
        <soap:body use="literal"/>
      </output>
      <fault name="sizeFault">
        <soap:body use="literal"/>
      </fault>
  </operation>
</binding>

This binding specifies that messages are sent using the document/literal message style.

6.2. Adding SOAP Headers to a SOAP 1.1 Binding

Overview

SOAP headers are defined by adding soap:header elements to your default SOAP 1.1 binding. The soap:header element is an optional child of the input, output, and fault elements of the binding. The SOAP header becomes part of the parent message. A SOAP header is defined by specifying a message and a message part. Each SOAP header can only contain one message part, but you can insert as many SOAP headers as needed.

Syntax

The syntax for defining a SOAP header is shown in Example 6.3, “SOAP Header Syntax”. The message attribute of soap:header is the qualified name of the message from which the part being inserted into the header is taken. The part attribute is the name of the message part inserted into the SOAP header. Because SOAP headers are always document style, the WSDL message part inserted into the SOAP header must be defined using an element. Together the message and the part attributes fully describe the data to insert into the SOAP header.

Example 6.3. SOAP Header Syntax

<binding name="headwig">
  <soap:binding style="document"
                transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="weave">
      <soap:operation soapAction="" style="document"/>
      <input name="grain">
        <soap:body ... />
        <soap:header message="QName" part="partName"/>
      </input>
...
</binding>

As well as the mandatory message and part attributes, soap:header also supports the namespace, the use, and the encodingStyle attributes. These attributes function the same for soap:header as they do for soap:body.

Splitting messages between body and header

The message part inserted into the SOAP header can be any valid message part from the contract. It can even be a part from the parent message which is being used as the SOAP body. Because it is unlikely that you would want to send information twice in the same message, the SOAP binding provides a means for specifying the message parts that are inserted into the SOAP body.

The soap:body element has an optional attribute, parts, that takes a space delimited list of part names. When parts is defined, only the message parts listed are inserted into the SOAP body. You can then insert the remaining parts into the SOAP header.

Note

When you define a SOAP header using parts of the parent message, Apache CXF automatically fills in the SOAP headers for you.

Example

Example 6.4, “SOAP 1.1 Binding with a SOAP Header” shows a modified version of the orderWidgets service shown in Example 6.1, “Ordering System Interface”. This version has been modified so that each order has an xsd:base64binary value placed in the SOAP header of the request and response. The SOAP header is defined as being the keyVal part from the widgetKey message. In this case you are responsible for adding the SOAP header to your application logic because it is not part of the input or output message.

Example 6.4. SOAP 1.1 Binding with a SOAP Header

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="widgetOrderForm.wsdl"
    targetNamespace="http://widgetVendor.com/widgetOrderForm"
    xmlns="http://schemas.xmlsoap.org/wsdl/"
    xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/"
    xmlns:tns="http://widgetVendor.com/widgetOrderForm"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:xsd1="http://widgetVendor.com/types/widgetTypes"
    xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">

<types>
  <schema targetNamespace="http://widgetVendor.com/types/widgetTypes"
           xmlns="http://www.w3.org/2001/XMLSchema"
           xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/">
    <element name="keyElem" type="xsd:base64Binary"/>
  </schema>
</types>

<message name="widgetOrder">
  <part name="numOrdered" type="xsd:int"/>
</message>
<message name="widgetOrderBill">
  <part name="price" type="xsd:float"/>
</message>
<message name="badSize">
  <part name="numInventory" type="xsd:int"/>
</message>
<message name="widgetKey">
  <part name="keyVal" element="xsd1:keyElem"/>
</message>

<portType name="orderWidgets">
  <operation name="placeWidgetOrder">
    <input message="tns:widgetOrder" name="order"/>
    <output message="tns:widgetOrderBill" name="bill"/>
    <fault message="tns:badSize" name="sizeFault"/>
  </operation>
</portType>

<binding name="orderWidgetsBinding" type="tns:orderWidgets">
  <soap:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="placeWidgetOrder">
      <soap:operation soapAction="" style="document"/>
      <input name="order">
        <soap:body use="literal"/>
        <soap:header message="tns:widgetKey" part="keyVal"/>
      </input>
      <output name="bill">
        <soap:body use="literal"/>
        <soap:header message="tns:widgetKey" part="keyVal"/>
      </output>
      <fault name="sizeFault">
        <soap:body use="literal"/>
      </fault>
  </operation>
</binding>
...
</definitions>

You can also modify Example 6.4, “SOAP 1.1 Binding with a SOAP Header” so that the header value is a part of the input and output messages.

Chapter 7. Using SOAP 1.2 Messages

Abstract

Apache CXF provides tools to generate a SOAP 1.2 binding which does not use any SOAP headers. You can add SOAP headers to your binding using any text or XML editor.

7.1. Adding a SOAP 1.2 Binding to a WSDL Document

Using wsdl2soap

Note

To use wsdl2soap you will need to download the Apache CXF distribution.

To generate a SOAP 1.2 binding using wsdl2soap use the following command: wsdl2soap-iport-type-name-bbinding-name-soap12-doutput-directory-ooutput-file-nsoap-body-namespace-style (document/rpc)-use (literal/encoded)-v-verbose-quietwsdlurl The tool has the following required arguments:

OptionInterpretation

-i port-type-name

Specifies the portType element for which a binding is generated.

-soap12

Specifies that the generated binding uses SOAP 1.2.

wsdlurl

The path and name of the WSDL file containing the portType element definition.

The tool has the following optional arguments:

OptionInterpretation

-b binding-name

Specifies the name of the generated SOAP binding.

-soap12

Specifies that the generated binding will use SOAP 1.2.

-d output-directory

Specifies the directory to place the generated WSDL file.

-o output-file

Specifies the name of the generated WSDL file.

-n soap-body-namespace

Specifies the SOAP body namespace when the style is RPC.

-style (document/rpc)

Specifies the encoding style (document or RPC) to use in the SOAP binding. The default is document.

-use (literal/encoded)

Specifies the binding use (encoded or literal) to use in the SOAP binding. The default is literal.

-v

Displays the version number for the tool.

-verbose

Displays comments during the code generation process.

-quiet

Suppresses comments during the code generation process.

The -i port-type-name and wsdlurl arguments are required. If the -style rpc argument is specified, the -n soap-body-namspace argument is also required. All other arguments are optional and can be listed in any order.

Important

wsdl2soap does not support the generation of document/encoded SOAP 1.2 bindings.

Example

If your system has an interface that takes orders and offers a single operation to process the orders it is defined in a WSDL fragment similar to the one shown in Example 7.1, “Ordering System Interface”.

Example 7.1. Ordering System Interface

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="widgetOrderForm.wsdl"
    targetNamespace="http://widgetVendor.com/widgetOrderForm"
    xmlns="http://schemas.xmlsoap.org/wsdl/"
    xmlns:soap12="http://schemas.xmlsoap.org/wsdl/soap12/"
    xmlns:tns="http://widgetVendor.com/widgetOrderForm"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:xsd1="http://widgetVendor.com/types/widgetTypes"
    xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">

<message name="widgetOrder">
  <part name="numOrdered" type="xsd:int"/>
</message>
<message name="widgetOrderBill">
  <part name="price" type="xsd:float"/>
</message>
<message name="badSize">
  <part name="numInventory" type="xsd:int"/>
</message>

<portType name="orderWidgets">
  <operation name="placeWidgetOrder">
    <input message="tns:widgetOrder" name="order"/>
    <output message="tns:widgetOrderBill" name="bill"/>
    <fault message="tns:badSize" name="sizeFault"/>
  </operation>
</portType>
...
</definitions>

The SOAP binding generated for orderWidgets is shown in Example 7.2, “SOAP 1.2 Binding for orderWidgets”.

Example 7.2. SOAP 1.2 Binding for orderWidgets

<binding name="orderWidgetsBinding" type="tns:orderWidgets">
  <soap12:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="placeWidgetOrder">
      <soap12:operation soapAction="" style="document"/>
      <input name="order">
        <soap12:body use="literal"/>
      </input>
      <output name="bill">
        <wsoap12:body use="literal"/>
      </output>
      <fault name="sizeFault">
        <soap12:body use="literal"/>
      </fault>
  </operation>
</binding>

This binding specifies that messages are sent using the document/literal message style.

7.2. Adding Headers to a SOAP 1.2 Message

Overview

SOAP message headers are defined by adding soap12:header elements to your SOAP 1.2 message. The soap12:header element is an optional child of the input, output, and fault elements of the binding. The SOAP header becomes part of the parent message. A SOAP header is defined by specifying a message and a message part. Each SOAP header can only contain one message part, but you can insert as many headers as needed.

Syntax

The syntax for defining a SOAP header is shown in Example 7.3, “SOAP Header Syntax”.

Example 7.3. SOAP Header Syntax

<binding name="headwig">
  <soap12:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="weave">
      <soap12:operation soapAction="" style="documment"/>
      <input name="grain">
        <soap12:body ... />
        <soap12:header message="QName" part="partName"
                       use="literal|encoded"
                        encodingStyle="encodingURI"
                        namespace="namespaceURI" />
      </input>
...
</binding>

The soap12:header element’s attributes are described in Table 7.1, “soap12:header Attributes”.

Table 7.1. soap12:header Attributes
AttributeDescription

message

A required attribute specifying the qualified name of the message from which the part being inserted into the header is taken.

part

A required attribute specifying the name of the message part inserted into the SOAP header.

use

Specifies if the message parts are to be encoded using encoding rules. If set to encoded the message parts are encoded using the encoding rules specified by the value of the encodingStyle attribute. If set to literal, the message parts are defined by the schema types referenced.

encodingStyle

Specifies the encoding rules used to construct the message.

namespace

Defines the namespace to be assigned to the header element serialized with use="encoded".

Splitting messages between body and header

The message part inserted into the SOAP header can be any valid message part from the contract. It can even be a part from the parent message which is being used as the SOAP body. Because it is unlikely that you would send information twice in the same message, the SOAP 1.2 binding provides a means for specifying the message parts that are inserted into the SOAP body.

The soap12:body element has an optional attribute, parts, that takes a space delimited list of part names. When parts is defined, only the message parts listed are inserted into the body of the SOAP 1.2 message. You can then insert the remaining parts into the message’s header.

Note

When you define a SOAP header using parts of the parent message, Apache CXF automatically fills in the SOAP headers for you.

Example

Example 7.4, “SOAP 1.2 Binding with a SOAP Header” shows a modified version of the orderWidgets service shown in Example 7.1, “Ordering System Interface”. This version is modified so that each order has an xsd:base64binary value placed in the header of the request and the response. The header is defined as being the keyVal part from the widgetKey message. In this case you are responsible for adding the application logic to create the header because it is not part of the input or output message.

Example 7.4. SOAP 1.2 Binding with a SOAP Header

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="widgetOrderForm.wsdl"
    targetNamespace="http://widgetVendor.com/widgetOrderForm"
    xmlns="http://schemas.xmlsoap.org/wsdl/"
    xmlns:soap12="http://schemas.xmlsoap.org/wsdl/soap12/"
    xmlns:tns="http://widgetVendor.com/widgetOrderForm"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:xsd1="http://widgetVendor.com/types/widgetTypes"
    xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">

<types>
  <schema targetNamespace="http://widgetVendor.com/types/widgetTypes"
           xmlns="http://www.w3.org/2001/XMLSchema"
           xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/">
    <element name="keyElem" type="xsd:base64Binary"/>
  </schema>
</types>

<message name="widgetOrder">
  <part name="numOrdered" type="xsd:int"/>
</message>
<message name="widgetOrderBill">
  <part name="price" type="xsd:float"/>
</message>
<message name="badSize">
  <part name="numInventory" type="xsd:int"/>
</message>
<message name="widgetKey">
  <part name="keyVal" element="xsd1:keyElem"/>
</message>

<portType name="orderWidgets">
  <operation name="placeWidgetOrder">
    <input message="tns:widgetOrder" name="order"/>
    <output message="tns:widgetOrderBill" name="bill"/>
    <fault message="tns:badSize" name="sizeFault"/>
  </operation>
</portType>

<binding name="orderWidgetsBinding" type="tns:orderWidgets">
  <soap12:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="placeWidgetOrder">
      <soap12:operation soapAction="" style="document"/>
      <input name="order">
        <soap12:body use="literal"/>
        <soap12:header message="tns:widgetKey" part="keyVal"/>
      </input>
      <output name="bill">
        <soap12:body use="literal"/>
        <soap12:header message="tns:widgetKey" part="keyVal"/>
      </output>
      <fault name="sizeFault">
        <soap12:body use="literal"/>
      </fault>
  </operation>
</binding>
...
</definitions>

You can modify Example 7.4, “SOAP 1.2 Binding with a SOAP Header” so that the header value is a part of the input and output messages, as shown in Example 7.5, “SOAP 1.2 Binding for orderWidgets with a SOAP Header”. In this case keyVal is a part of the input and output messages. In the soap12:body elements the parts attribute specifies that keyVal should not be inserted into the body. However, it is inserted into the header.

Example 7.5. SOAP 1.2 Binding for orderWidgets with a SOAP Header

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="widgetOrderForm.wsdl"
    targetNamespace="http://widgetVendor.com/widgetOrderForm"
    xmlns="http://schemas.xmlsoap.org/wsdl/"
    xmlns:soap12="http://schemas.xmlsoap.org/wsdl/soap12/"
    xmlns:tns="http://widgetVendor.com/widgetOrderForm"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:xsd1="http://widgetVendor.com/types/widgetTypes"
    xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">

<types>
  <schema targetNamespace="http://widgetVendor.com/types/widgetTypes"
           xmlns="http://www.w3.org/2001/XMLSchema"
           xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/">
    <element name="keyElem" type="xsd:base64Binary"/>
  </schema>
</types>

<message name="widgetOrder">
  <part name="numOrdered" type="xsd:int"/>
  <part name="keyVal" element="xsd1:keyElem"/>
</message>
<message name="widgetOrderBill">
  <part name="price" type="xsd:float"/>
  <part name="keyVal" element="xsd1:keyElem"/>
</message>
<message name="badSize">
  <part name="numInventory" type="xsd:int"/>
</message>

<portType name="orderWidgets">
  <operation name="placeWidgetOrder">
    <input message="tns:widgetOrder" name="order"/>
    <output message="tns:widgetOrderBill" name="bill"/>
    <fault message="tns:badSize" name="sizeFault"/>
  </operation>
</portType>

<binding name="orderWidgetsBinding" type="tns:orderWidgets">
  <soap12:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="placeWidgetOrder">
      <soap12:operation soapAction="" style="document"/>
      <input name="order">
        <soap12:body use="literal" parts="numOrdered"/>
        <soap12:header message="tns:widgetOrder" part="keyVal"/>
      </input>
      <output name="bill">
        <soap12:body use="literal" parts="bill"/>
        <soap12:header message="tns:widgetOrderBill" part="keyVal"/>
      </output>
      <fault name="sizeFault">
        <soap12:body use="literal"/>
      </fault>
  </operation>
</binding>
...
</definitions>

Chapter 8. Sending Binary Data Using SOAP with Attachments

Abstract

SOAP attachments provide a mechanism for sending binary data as part of a SOAP message. Using SOAP with attachments requires that you define your SOAP messages as MIME multipart messages.

Overview

SOAP messages generally do not carry binary data. However, the W3C SOAP 1.1 specification allows for using MIME multipart/related messages to send binary data in SOAP messages. This technique is called using SOAP with attachments. SOAP attachments are defined in the W3C’s SOAP Messages with Attachments Note.

Namespace

The WSDL extensions used to define the MIME multipart/related messages are defined in the namespace http://schemas.xmlsoap.org/wsdl/mime/.

In the discussion that follows, it is assumed that this namespace is prefixed with mime. The entry in the WSDL definitions element to set this up is shown in Example 8.1, “MIME Namespace Specification in a Contract”.

Example 8.1. MIME Namespace Specification in a Contract

xmlns:mime="http://schemas.xmlsoap.org/wsdl/mime/"

Changing the message binding

In a default SOAP binding, the first child element of the input, output, and fault elements is a soap:body element describing the body of the SOAP message representing the data. When using SOAP with attachments, the soap:body element is replaced with a mime:multipartRelated element.

Note

WSDL does not support using mime:multipartRelated for fault messages.

The mime:multipartRelated element tells Apache CXF that the message body is a multipart message that potentially contains binary data. The contents of the element define the parts of the message and their contents. mime:multipartRelated elements contain one or more mime:part elements that describe the individual parts of the message.

The first mime:part element must contain the soap:body element that would normally appear in a default SOAP binding. The remaining mime:part elements define the attachments that are being sent in the message.

Describing a MIME multipart message

MIME multipart messages are described using a mime:multipartRelated element that contains a number of mime:part elements. To fully describe a MIME multipart message you must do the following:

  1. Inside the input or output message you are sending as a MIME multipart message, add a mime:mulipartRelated element as the first child element of the enclosing message.
  2. Add a mime:part child element to the mime:multipartRelated element and set its name attribute to a unique string.
  3. Add a soap:body element as the child of the mime:part element and set its attributes appropriately.

    Note

    If the contract had a default SOAP binding, you can copy the soap:body element from the corresponding message from the default binding into the MIME multipart message.

  4. Add another mime:part child element to the mime:multipartReleated element and set its name attribute to a unique string.
  5. Add a mime:content child element to the mime:part element to describe the contents of this part of the message.

    To fully describe the contents of a MIME message part the mime:content element has the following attributes:

    Table 8.1. mime:content Attributes
    AttributeDescription +

    part

    Specifies the name of the WSDL message part, from the parent message definition, that is used as the content of this part of the MIME multipart message being placed on the wire.

    +

    type

    The MIME type of the data in this message part. MIME types are defined as a type and a subtype using the syntax type/subtype.

    +

    There are a number of predefined MIME types such as image/jpeg and text/plain. The MIME types are maintained by the Internet Assigned Numbers Authority (IANA) and described in detail in Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies and Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types.

    +

  6. For each additional MIME part, repeat steps [i303819] and [i303821].

Example

Example 8.2, “Contract using SOAP with Attachments” shows a WSDL fragment defining a service that stores X-rays in JPEG format. The image data, xRay, is stored as an xsd:base64binary and is packed into the MIME multipart message’s second part, imageData. The remaining two parts of the input message, patientName and patientNumber, are sent in the first part of the MIME multipart image as part of the SOAP body.

Example 8.2. Contract using SOAP with Attachments

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="XrayStorage"
    targetNamespace="http://mediStor.org/x-rays"
    xmlns="http://schemas.xmlsoap.org/wsdl/"
    xmlns:tns="http://mediStor.org/x-rays"
    xmlns:mime="http://schemas.xmlsoap.org/wsdl/mime/"
    xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema">

  <message name="storRequest">
    <part name="patientName" type="xsd:string"/>
    <part name="patientNumber" type="xsd:int"/>
    <part name="xRay" type="xsd:base64Binary"/>
  </message>
  <message name="storResponse">
    <part name="success" type="xsd:boolean"/>
  </message>

  <portType name="xRayStorage">
    <operation name="store">
      <input message="tns:storRequest" name="storRequest"/>
      <output message="tns:storResponse" name="storResponse"/>
    </operation>
  </portType>

  <binding name="xRayStorageBinding" type="tns:xRayStorage">
    <soap:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
      <operation name="store">
      <soap:operation soapAction="" style="document"/>
      <input name="storRequest">
        <mime:multipartRelated>
          <mime:part name="bodyPart">
            <soap:body use="literal"/>
          </mime:part>
          <mime:part name="imageData">
            <mime:content part="xRay" type="image/jpeg"/>
          </mime:part>
        </mime:multipartRelated>
      </input>
      <output name="storResponse">
        <soap:body use="literal"/>
      </output>
    </operation>
  </binding>

  <service name="xRayStorageService">
    <port binding="tns:xRayStorageBinding" name="xRayStoragePort">
      <soap:address location="http://localhost:9000"/>
    </port>
  </service>
</definitions>

Chapter 9. Sending Binary Data with SOAP MTOM

Abstract

SOAP Message Transmission Optimization Mechanism (MTOM) replaces SOAP with attachments as a mechanism for sending binary data as part of an XML message. Using MTOM with Apache CXF requires adding the correct schema types to a service’s contract and enabling the MTOM optimizations.

9.1. Overview of MTOM

SOAP Message Transmission Optimization Mechanism (MTOM) specifies an optimized method for sending binary data as part of a SOAP message. Unlike SOAP with Attachments, MTOM requires the use of XML-binary Optimized Packaging (XOP) packages for transmitting binary data. Using MTOM to send binary data does not require you to fully define the MIME Multipart/Related message as part of the SOAP binding. It does, however, require that you do the following:

  1. Annotate the data that you are going to send as an attachment.

    You can annotate either your WSDL or the Java class that implements your data.

  2. Enable the runtime’s MTOM support.

    This can be done either programmatically or through configuration.

  3. Develop a DataHandler for the data being passed as an attachment.

    Note

    Developing DataHandlers is beyond the scope of this book.

9.2. Annotating Data Types to use MTOM

Overview

In WSDL, when defining a data type for passing along a block of binary data, such as an image file or a sound file, you define the element for the data to be of type xsd:base64Binary. By default, any element of type xsd:base64Binary results in the generation of a byte[] which can be serialized using MTOM. However, the default behavior of the code generators does not take full advantage of the serialization.

In order to fully take advantage of MTOM you must add annotations to either your service’s WSDL document or the JAXB class that implements the binary data structure. Adding the annotations to the WSDL document forces the code generators to generate streaming data handlers for the binary data. Annotating the JAXB class involves specifying the proper content types and might also involve changing the type specification of the field containing the binary data.

WSDL first

Example 9.1, “Message for MTOM” shows a WSDL document for a Web service that uses a message which contains one string field, one integer field, and a binary field. The binary field is intended to carry a large image file, so it is not appropriate to send it as part of a normal SOAP message.

Example 9.1. Message for MTOM

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="XrayStorage"
    targetNamespace="http://mediStor.org/x-rays"
    xmlns="http://schemas.xmlsoap.org/wsdl/"
    xmlns:tns="http://mediStor.org/x-rays"
    xmlns:soap12="http://schemas.xmlsoap.org/wsdl/soap12/"
    xmlns:xsd1="http://mediStor.org/types/"
    xmlns:xsd="http://www.w3.org/2001/XMLSchema">

  <types>
    <schema targetNamespace="http://mediStor.org/types/"
            xmlns="http://www.w3.org/2001/XMLSchema">
      <complexType name="xRayType">
        <sequence>
          <element name="patientName" type="xsd:string" />
          <element name="patientNumber" type="xsd:int" />
          <element name="imageData" type="xsd:base64Binary" />
        </sequence>
      </complexType>
      <element name="xRay" type="xsd1:xRayType" />
    </schema>
  </types>

  <message name="storRequest">
    <part name="record" element="xsd1:xRay"/>
  </message>
  <message name="storResponse">
    <part name="success" type="xsd:boolean"/>
  </message>

  <portType name="xRayStorage">
    <operation name="store">
      <input message="tns:storRequest" name="storRequest"/>
      <output message="tns:storResponse" name="storResponse"/>
    </operation>
  </portType>

  <binding name="xRayStorageSOAPBinding" type="tns:xRayStorage">
    <soap12:binding style="document" transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="store">
      <soap12:operation soapAction="" style="document"/>
      <input name="storRequest">
        <soap12:body use="literal"/>
      </input>
      <output name="storResponse">
        <soap12:body use="literal"/>
      </output>
    </operation>
  </binding>
  ...
</definitions>

If you want to use MTOM to send the binary part of the message as an optimized attachment you must add the xmime:expectedContentTypes attribute to the element containing the binary data. This attribute is defined in the http://www.w3.org/2005/05/xmlmime namespace and specifies the MIME types that the element is expected to contain. You can specify a comma separated list of MIME types. The setting of this attribute changes how the code generators create the JAXB class for the data. For most MIME types, the code generator creates a DataHandler. Some MIME types, such as those for images, have defined mappings.

Note

The MIME types are maintained by the Internet Assigned Numbers Authority(IANA) and are described in detail in Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies and Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types.

For most uses you specify application/octet-stream.

Example 9.2, “Binary Data for MTOM” shows how you can modify xRayType from Example 9.1, “Message for MTOM” for using MTOM.

Example 9.2. Binary Data for MTOM

...
  <types>
    <schema targetNamespace="http://mediStor.org/types/"
            xmlns="http://www.w3.org/2001/XMLSchema"
            xmlns:xmime="http://www.w3.org/2005/05/xmlmime">
      <complexType name="xRayType">
        <sequence>
          <element name="patientName" type="xsd:string" />
          <element name="patientNumber" type="xsd:int" />
          <element name="imageData" type="xsd:base64Binary"
                   xmime:expectedContentTypes="application/octet-stream"/>
        </sequence>
      </complexType>
      <element name="xRay" type="xsd1:xRayType" />
    </schema>
  </types>
...

The generated JAXB class generated for xRayType no longer contains a byte[]. Instead the code generator sees the xmime:expectedContentTypes attribute and generates a DataHandler for the imageData field.

Note

You do not need to change the binding element to use MTOM. The runtime makes the appropriate changes when the data is sent.

Java first

If you are doing Java first development you can make your JAXB class MTOM ready by doing the following:

  1. Make sure the field holding the binary data is a DataHandler.
  2. Add the @XmlMimeType() annotation to the field containing the data you want to stream as an MTOM attachment.

Example 9.3, “JAXB Class for MTOM” shows a JAXB class annotated for using MTOM.

Example 9.3. JAXB Class for MTOM

@XmlType
public class XRayType {
    protected String patientName;
    protected int patientNumber;
    @XmlMimeType("application/octet-stream")
    protected DataHandler imageData;
  ...
}

9.3. Enabling MTOM

By default the Apache CXF runtime does not enable MTOM support. It sends all binary data as either part of the normal SOAP message or as an unoptimized attachment. You can activate MTOM support either programmatically or through the use of configuration.

9.3.1. Using JAX-WS APIs

Overview

Both service providers and consumers must have the MTOM optimizations enabled. The JAX-WS APIs offer different mechanisms for each type of endpoint.

Service provider

If you published your service provider using the JAX-WS APIs you enable the runtime’s MTOM support as follows:

  1. Access the Endpoint object for your published service.

    The easiest way to access the Endpoint object is when you publish the endpoint. For more information see Chapter 31, Publishing a Service.

  2. Get the SOAP binding from the Endpoint using its getBinding() method, as shown in Example 9.4, “Getting the SOAP Binding from an Endpoint”.

    Example 9.4. Getting the SOAP Binding from an Endpoint

    // Endpoint ep is declared previously
    SOAPBinding binding = (SOAPBinding)ep.getBinding();

    You must cast the returned binding object to a SOAPBinding object to access the MTOM property.

  3. Set the binding’s MTOM enabled property to true using the binding’s setMTOMEnabled() method, as shown in Example 9.5, “Setting a Service Provider’s MTOM Enabled Property”.

    Example 9.5. Setting a Service Provider’s MTOM Enabled Property

    binding.setMTOMEnabled(true);
Consumer

To MTOM enable a JAX-WS consumer you must do the following:

  1. Cast the consumer’s proxy to a BindingProvider object.

    For information on getting a consumer proxy see Chapter 25, Developing a Consumer Without a WSDL Contract or Chapter 28, Developing a Consumer From a WSDL Contract.

  2. Get the SOAP binding from the BindingProvider using its getBinding() method, as shown in Example 9.6, “Getting a SOAP Binding from a BindingProvider.

    Example 9.6. Getting a SOAP Binding from a BindingProvider

    // BindingProvider bp declared previously
    SOAPBinding binding = (SOAPBinding)bp.getBinding();
  3. Set the bindings MTOM enabled property to true using the binding’s setMTOMEnabled() method, as shown in Example 9.7, “Setting a Consumer’s MTOM Enabled Property”.

    Example 9.7. Setting a Consumer’s MTOM Enabled Property

    binding.setMTOMEnabled(true);

9.3.2. Using configuration

Overview

If you publish your service using XML, such as when deploying to a container, you can enable your endpoint’s MTOM support in the endpoint’s configuration file. For more information on configuring endpoint’s see Part IV, “Configuring Web Service Endpoints”.

Procedure

The MTOM property is set inside the jaxws:endpoint element for your endpoint. To enable MTOM do the following:

  1. Add a jaxws:property child element to the endpoint’s jaxws:endpoint element.
  2. Add a entry child element to the jaxws:property element.
  3. Set the entry element’s key attribute to mtom-enabled.
  4. Set the entry element’s value attribute to true.
Example

Example 9.8, “Configuration for Enabling MTOM” shows an endpoint that is MTOM enabled.

Example 9.8. Configuration for Enabling MTOM

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:jaxws="http://cxf.apache.org/jaxws"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
                           http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
                           http://cxf.apache.org/jaxws http://cxf.apache.org/schema/jaxws.xsd">

  <jaxws:endpoint id="xRayStorage"
                  implementor="demo.spring.xRayStorImpl"
                  address="http://localhost/xRayStorage">
    <jaxws:properties>
      <entry key="mtom-enabled" value="true"/>
    </jaxws:properties>
  </jaxws:endpoint>
</beans>

Chapter 10. Using XML Documents

Abstract

The pure XML payload format provides an alternative to the SOAP binding by allowing services to exchange data using straight XML documents without the overhead of a SOAP envelope.

XML binding namespace

The extensions used to describe XML format bindings are defined in the namespace http://cxf.apache.org/bindings/xformat. Apache CXF tools use the prefix xformat to represent the XML binding extensions. Add the following line to your contracts:

xmlns:xformat="http://cxf.apache.org/bindings/xformat"

Hand editing

To map an interface to a pure XML payload format do the following:

  1. Add the namespace declaration to include the extensions defining the XML binding. See the section called “XML binding namespace”.
  2. Add a standard WSDL binding element to your contract to hold the XML binding, give the binding a unique name, and specify the name of the WSDL portType element that represents the interface being bound.
  3. Add an xformat:binding child element to the binding element to identify that the messages are being handled as pure XML documents without SOAP envelopes.
  4. Optionally, set the xformat:binding element’s rootNode attribute to a valid QName. For more information on the effect of the rootNode attribute see the section called “XML messages on the wire”.
  5. For each operation defined in the bound interface, add a standard WSDL operation element to hold the binding information for the operation’s messages.
  6. For each operation added to the binding, add the input, output, and fault children elements to represent the messages used by the operation.

    These elements correspond to the messages defined in the interface definition of the logical operation.

  7. Optionally add an xformat:body element with a valid rootNode attribute to the added input, output, and fault elements to override the value of rootNode set at the binding level.
Note

If any of your messages have no parts, for example the output message for an operation that returns void, you must set the rootNode attribute for the message to ensure that the message written on the wire is a valid, but empty, XML document.

XML messages on the wire

When you specify that an interface’s messages are to be passed as XML documents, without a SOAP envelope, you must take care to ensure that your messages form valid XML documents when they are written on the wire. You also need to ensure that non-Apache CXF participants that receive the XML documents understand the messages generated by Apache CXF.

A simple way to solve both problems is to use the optional rootNode attribute on either the global xformat:binding element or on the individual message’s xformat:body elements. The rootNode attribute specifies the QName for the element that serves as the root node for the XML document generated by Apache CXF. When the rootNode attribute is not set, Apache CXF uses the root element of the message part as the root element when using doc style messages, or an element using the message part name as the root element when using rpc style messages.

For example, if the rootNode attribute is not set the message defined in Example 10.1, “Valid XML Binding Message” would generate an XML document with the root element lineNumber.

Example 10.1. Valid XML Binding Message

<type ... >
  ...
  <element name="operatorID" type="xsd:int"/>
  ...
</types>
<message name="operator">
  <part name="lineNumber" element="ns1:operatorID"/>
</message>

For messages with one part, Apache CXF will always generate a valid XML document even if the rootNode attribute is not set. However, the message in Example 10.2, “Invalid XML Binding Message” would generate an invalid XML document.

Example 10.2. Invalid XML Binding Message

<types>
  ...
  <element name="pairName" type="xsd:string"/>
  <element name="entryNum" type="xsd:int"/>
  ...
</types>

<message name="matildas">
  <part name="dancing" element="ns1:pairName"/>
  <part name="number" element="ns1:entryNum"/>
</message>

Without the rootNode attribute specified in the XML binding, Apache CXF will generate an XML document similar to Example 10.3, “Invalid XML Document” for the message defined in Example 10.2, “Invalid XML Binding Message”. The generated XML document is invalid because it has two root elements: pairName and entryNum.

Example 10.3. Invalid XML Document

<pairName>
  Fred&Linda
</pairName>
<entryNum>
  123
</entryNum>

If you set the rootNode attribute, as shown in Example 10.4, “XML Binding with rootNode set” Apache CXF will wrap the elements in the specified root element. In this example, the rootNode attribute is defined for the entire binding and specifies that the root element will be named entrants.

Example 10.4. XML Binding with rootNode set

<portType name="danceParty">
  <operation name="register">
    <input message="tns:matildas" name="contestant"/>
  </operation>
</portType>

<binding name="matildaXMLBinding" type="tns:dancingMatildas">
  <xmlformat:binding rootNode="entrants"/>
  <operation name="register">
    <input name="contestant"/>
    <output name="entered"/>
</binding>

An XML document generated from the input message would be similar to Example 10.5, “XML Document generated using the rootNode attribute”. Notice that the XML document now only has one root element.

Example 10.5. XML Document generated using the rootNode attribute

<entrants>
  <pairName>
    Fred&Linda
  <entryNum>
    123
  </entryNum>
</entrants>

Overriding the binding’s rootNode attribute setting

You can also set the rootNode attribute for each individual message, or override the global setting for a particular message, by using the xformat:body element inside of the message binding. For example, if you wanted the output message defined in Example 10.4, “XML Binding with rootNode set” to have a different root element from the input message, you could override the binding’s root element as shown in Example 10.6, “Using xformat:body.

Example 10.6. Using xformat:body

<binding name="matildaXMLBinding" type="tns:dancingMatildas">
  <xmlformat:binding rootNode="entrants"/>
  <operation name="register">
    <input name="contestant"/>
    <output name="entered">
      <xformat:body rootNode="entryStatus" />
    </output>
  </operation>
</binding>

Part III. Web Services Transports

This part describes how to add Apache CXF transports to a WSDL document.

Chapter 11. Understanding How Endpoints are Defined in WSDL

Abstract

Endpoints represent an instantiated service. They are defined by combining a binding and the networking details used to expose the endpoint.

Overview

An endpoint can be thought of as a physical manifestation of a service. It combines a binding, which specifies the physical representation of the logical data used by a service, and a set of networking details that define the physical connection details used to make the service contactable by other endpoints.

Note

CXF providers are servers for CXF consumers, which correspond to clients. If you are using the CXF (camel-cxf) component as the starting endpoint in a route, then the endpoint is both a Camel consumer and a CXF provider. If you are using the Camel CXF component, as an ending endpoint in a route, then the endpoint is both a Camel producer and a CXF consumer.

Endpoints and services

In the same way a binding can only map a single interface, an endpoint can only map to a single service. However, a service can be manifested by any number of endpoints. For example, you could define a ticket selling service that was manifested by four different endpoints. However, you could not have a single endpoint that manifested both a ticket selling service and a widget selling service.

The WSDL elements

Endpoints are defined in a contract using a combination of the WSDL service element and the WSDL port element. The service element is a collection of related port elements. The port elements define the actual endpoints.

The WSDL service element has a single attribute, name, that specifies a unique name. The service element is used as the parent element of a collection of related port elements. WSDL makes no specification about how the port elements are related. You can associate the port elements in any manner you see fit.

The WSDL port element has a has a binding attribute, that specifies the binding used by the endpoint and is a reference to the wsdl:binding element. It also includes the name attribute, which is a mandatory attribute that provides a unique name among all ports. The port element is the parent element of the elements that specify the actual transport details used by the endpoint. The elements used to specify the transport details are discussed in the following sections.

Adding endpoints to a contract

Apache CXF provides command line tools that can generated endpoints for predefined service interface and binding combinations.

The tools will add the proper elements to your contract for you. However, it is recommended that you have some knowledge of how the different transports used in defining an endpoint work.

You can also add an endpoint to a contract using any text editor. When you hand edit a contract, you are responsible for ensuring that the contract is valid.

Supported transports

Endpoint definitions are built using extensions defined for each of the transports Apache CXF supports. This includes the following transports:

  • HTTP
  • CORBA
  • Java Messaging Service

Chapter 12. Using HTTP

Abstract

HTTP is the underlying transport for the Web. It provides a standardized, robust, and flexible platform for communicating between endpoints. Because of these factors it is the assumed transport for most WS-* specifications and is integral to RESTful architectures.

12.1. Adding a Basic HTTP Endpoint

Alternative HTTP runtimes

Apache CXF supports the following alternative HTTP runtime implementations:

Netty HTTP URL

Normally, a HTTP endpoint uses whichever HTTP runtime is included on the classpath (either Undertow or Netty). If both the Undertow runtime and Netty runtime are included on the classpath, however, you need to specify explicitly when you want to use the Netty runtime, because the Undertow runtime will be used by default.

In the case where more than one HTTP runtime is available on the classpath, you can select the Undertow runtime by specifying the endpoint URL to have the following format:

netty://http://RestOfURL

Payload types

There are three ways of specifying an HTTP endpoint’s address depending on the payload format you are using.

  • SOAP 1.1 uses the standardized soap:address element.
  • SOAP 1.2 uses the soap12:address element.
  • All other payload formats use the http:address element.
Note

From Camel 2.16.0 release, Apache Camel CXF Payload supports stream cache out of box.

SOAP 1.1

When you are sending SOAP 1.1 messages over HTTP you must use the SOAP 1.1 address element to specify the endpoint’s address. It has one attribute, location, that specifies the endpoint’s address as a URL. The SOAP 1.1 address element is defined in the namespace http://schemas.xmlsoap.org/wsdl/soap/.

Example 12.1, “SOAP 1.1 Port Element” shows a port element used to send SOAP 1.1 messages over HTTP.

Example 12.1. SOAP 1.1 Port Element

<definitions ...
             xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" ...>
  ...
  <service name="SOAP11Service">
    <port binding="SOAP11Binding" name="SOAP11Port">
      <soap:address location="http://artie.com/index.xml">
    </port>
  </service>
  ...
<definitions>

SOAP 1.2

When you are sending SOAP 1.2 messages over HTTP you must use the SOAP 1.2 address element to specify the endpoint’s address. It has one attribute, location, that specifies the endpoint’s address as a URL. The SOAP 1.2 address element is defined in the namespace http://schemas.xmlsoap.org/wsdl/soap12/.

Example 12.2, “SOAP 1.2 Port Element” shows a port element used to send SOAP 1.2 messages over HTTP.

Example 12.2. SOAP 1.2 Port Element

<definitions ...
             xmlns:soap12="http://schemas.xmlsoap.org/wsdl/soap12/" ... >
  <service name="SOAP12Service">
    <port binding="SOAP12Binding" name="SOAP12Port">
      <soap12:address location="http://artie.com/index.xml">
    </port>
  </service>
  ...
</definitions>

Other messages types

When your messages are mapped to any payload format other than SOAP you must use the HTTP address element to specify the endpoint’s address. It has one attribute, location, that specifies the endpoint’s address as a URL. The HTTP address element is defined in the namespace http://schemas.xmlsoap.org/wsdl/http/.

Example 12.3, “HTTP Port Element” shows a port element used to send an XML message.

Example 12.3. HTTP Port Element

<definitions ...
             xmlns:http="http://schemas.xmlsoap.org/wsdl/http/" ... >
  <service name="HTTPService">
    <port binding="HTTPBinding" name="HTTPPort">
      <http:address location="http://artie.com/index.xml">
    </port>
  </service>
  ...
</definitions>

12.2. Configuring a Consumer

12.2.1. Mechanisms for HTTP Consumer Endpoints

HTTP consumer endpoints can specify a number of HTTP connection attributes including whether the endpoint automatically accepts redirect responses, whether the endpoint can use chunking, whether the endpoint will request a keep-alive, and how the endpoint interacts with proxies. In addition to the HTTP connection properties, an HTTP consumer endpoint can specify how it is secured.

A consumer endpoint can be configured using two mechanisms:

12.2.2. Using Configuration

Namespace

The elements used to configure an HTTP consumer endpoint are defined in the namespace http://cxf.apache.org/transports/http/configuration. It is commonly referred to using the prefix http-conf. In order to use the HTTP configuration elements you must add the lines shown in Example 12.4, “HTTP Consumer Configuration Namespace” to the beans element of your endpoint’s configuration file. In addition, you must add the configuration elements' namespace to the xsi:schemaLocation attribute.

Example 12.4. HTTP Consumer Configuration Namespace

<beans ...
       xmlns:http-conf="http://cxf.apache.org/transports/http/configuration"
       ...
       xsi:schemaLocation="...
                           http://cxf.apache.org/transports/http/configuration
                              http://cxf.apache.org/schemas/configuration/http-conf.xsd
                          ...">
Undertow runtime or Netty runtime

You can use the elements from the http-conf namespace to configure either the Undertow runtime or the Netty runtime.

The conduit element

You configure an HTTP consumer endpoint using the http-conf:conduit element and its children. The http-conf:conduit element takes a single attribute, name, that specifies the WSDL port element corresponding to the endpoint. The value for the name attribute takes the form portQName`.http-conduit`. Example 12.5, “http-conf:conduit Element” shows the http-conf:conduit element that would be used to add configuration for an endpoint that is specified by the WSDL fragment <port binding="widgetSOAPBinding" name="widgetSOAPPort> when the endpoint’s target namespace is http://widgets.widgetvendor.net.

Example 12.5. http-conf:conduit Element

...
  <http-conf:conduit name="{http://widgets/widgetvendor.net}widgetSOAPPort.http-conduit">
    ...
  </http-conf:conduit>
...

The http-conf:conduit element has child elements that specify configuration information. They are described in Table 12.1, “Elements Used to Configure an HTTP Consumer Endpoint”.

Table 12.1. Elements Used to Configure an HTTP Consumer Endpoint
ElementDescription

http-conf:client

Specifies the HTTP connection properties such as timeouts, keep-alive requests, content types, etc. See the section called “The client element”.

http-conf:authorization

Specifies the parameters for configuring the basic authentication method that the endpoint uses preemptively. The preferred approach is to supply a http-conf:basicAuthSupplier object.

http-conf:proxyAuthorization

Specifies the parameters for configuring basic authentication against outgoing HTTP proxy servers.

http-conf:tlsClientParameters

Specifies the parameters used to configure SSL/TLS.

http-conf:basicAuthSupplier

Specifies the bean reference or class name of the object that supplies the basic authentication information used by the endpoint, either preemptively or in response to a 401 HTTP challenge.

http-conf:trustDecider

Specifies the bean reference or class name of the object that checks the HTTP(S) URLConnection object to establish trust for a connection with an HTTPS service provider before any information is transmitted.

The client element

The http-conf:client element is used to configure the non-security properties of a consumer endpoint’s HTTP connection. Its attributes, described in Table 12.2, “HTTP Consumer Configuration Attributes”, specify the connection’s properties.

Table 12.2. HTTP Consumer Configuration Attributes
AttributeDescription

ConnectionTimeout

Specifies the amount of time, in milliseconds, that the consumer attempts to establish a connection before it times out. The default is 30000.

0 specifies that the consumer will continue to send the request indefinitely.

ReceiveTimeout

Specifies the amount of time, in milliseconds, that the consumer will wait for a response before it times out. The default is 30000.

0 specifies that the consumer will wait indefinitely.

AutoRedirect

Specifies if the consumer will automatically follow a server issued redirection. The default is false.

MaxRetransmits

Specifies the maximum number of times a consumer will retransmit a request to satisfy a redirect. The default is -1 which specifies that unlimited retransmissions are allowed.

AllowChunking

Specifies whether the consumer will send requests using chunking. The default is true which specifies that the consumer will use chunking when sending requests.

Chunking cannot be used if either of the following are true:

  • http-conf:basicAuthSupplier is configured to provide credentials preemptively.
  • AutoRedirect is set to true.

In both cases the value of AllowChunking is ignored and chunking is disallowed.

Accept

Specifies what media types the consumer is prepared to handle. The value is used as the value of the HTTP Accept property. The value of the attribute is specified using multipurpose internet mail extensions (MIME) types.

AcceptLanguage

Specifies what language (for example, American English) the consumer prefers for the purpose of receiving a response. The value is used as the value of the HTTP AcceptLanguage property.

Language tags are regulated by the International Organization for Standards (ISO) and are typically formed by combining a language code, determined by the ISO-639 standard, and country code, determined by the ISO-3166 standard, separated by a hyphen. For example, en-US represents American English.

AcceptEncoding

Specifies what content encodings the consumer is prepared to handle. Content encoding labels are regulated by the Internet Assigned Numbers Authority (IANA). The value is used as the value of the HTTP AcceptEncoding property.

ContentType

Specifies the media type of the data being sent in the body of a message. Media types are specified using multipurpose internet mail extensions (MIME) types. The value is used as the value of the HTTP ContentType property. The default is text/xml.

For web services, this should be set to text/xml. If the client is sending HTML form data to a CGI script, this should be set to application/x-www-form-urlencoded. If the HTTP POST request is bound to a fixed payload format (as opposed to SOAP), the content type is typically set to application/octet-stream.

Host

Specifies the Internet host and port number of the resource on which the request is being invoked. The value is used as the value of the HTTP Host property.

This attribute is typically not required. It is only required by certain DNS scenarios or application designs. For example, it indicates what host the client prefers for clusters (that is, for virtual servers mapping to the same Internet protocol (IP) address).

Connection

Specifies whether a particular connection is to be kept open or closed after each request/response dialog. There are two valid values:

  • Keep-Alive — Specifies that the consumer wants the connection kept open after the initial request/response sequence. If the server honors it, the connection is kept open until the consumer closes it.
  • close(default) — Specifies that the connection to the server is closed after each request/response sequence.

CacheControl

Specifies directives about the behavior that must be adhered to by caches involved in the chain comprising a request from a consumer to a service provider. See Section 12.2.4, “Consumer Cache Control Directives”.

Cookie

Specifies a static cookie to be sent with all requests.

BrowserType

Specifies information about the browser from which the request originates. In the HTTP specification from the World Wide Web consortium (W3C) this is also known as the user-agent. Some servers optimize based on the client that is sending the request.

Referer

Specifies the URL of the resource that directed the consumer to make requests on a particular service. The value is used as the value of the HTTP Referer property.

This HTTP property is used when a request is the result of a browser user clicking on a hyperlink rather than typing a URL. This can allow the server to optimize processing based upon previous task flow, and to generate lists of back-links to resources for the purposes of logging, optimized caching, tracing of obsolete or mistyped links, and so on. However, it is typically not used in web services applications.

If the AutoRedirect attribute is set to true and the request is redirected, any value specified in the Referer attribute is overridden. The value of the HTTP Referer property is set to the URL of the service that redirected the consumer’s original request.

DecoupledEndpoint

Specifies the URL of a decoupled endpoint for the receipt of responses over a separate provider→consumer connection. For more information on using decoupled endpoints see, Section 12.6, “Using the HTTP Transport in Decoupled Mode”.

You must configure both the consumer endpoint and the service provider endpoint to use WS-Addressing for the decoupled endpoint to work.

ProxyServer

Specifies the URL of the proxy server through which requests are routed.

ProxyServerPort

Specifies the port number of the proxy server through which requests are routed.

ProxyServerType

Specifies the type of proxy server used to route requests. Valid values are:

  • HTTP(default)
  • SOCKS
Example

Example 12.6, “HTTP Consumer Endpoint Configuration” shows the configuration of an HTTP consumer endpoint that wants to keep its connection to the provider open between requests, that will only retransmit requests once per invocation, and that cannot use chunking streams.

Example 12.6. HTTP Consumer Endpoint Configuration

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:http-conf="http://cxf.apache.org/transports/http/configuration"
       xsi:schemaLocation="http://cxf.apache.org/transports/http/configuration
                             http://cxf.apache.org/schemas/configuration/http-conf.xsd
                           http://www.springframework.org/schema/beans
                             http://www.springframework.org/schema/beans/spring-beans.xsd">

  <http-conf:conduit name="{http://apache.org/hello_world_soap_http}SoapPort.http-conduit">
    <http-conf:client Connection="Keep-Alive"
                      MaxRetransmits="1"
                      AllowChunking="false" />
  </http-conf:conduit>
</beans>
More information

For more information on HTTP conduits see Chapter 16, Conduits.

12.2.3. Using WSDL

Namespace

The WSDL extension elements used to configure an HTTP consumer endpoint are defined in the namespace http://cxf.apache.org/transports/http/configuration. It is commonly referred to using the prefix http-conf. In order to use the HTTP configuration elements you must add the line shown in Example 12.7, “HTTP Consumer WSDL Element’s Namespace” to the definitions element of your endpoint’s WSDL document.

Example 12.7. HTTP Consumer WSDL Element’s Namespace

<definitions ...
       xmlns:http-conf="http://cxf.apache.org/transports/http/configuration"
Undertow runtime or Netty runtime

You can use the elements from the http-conf namespace to configure either the Undertow runtime or the Netty runtime.

The client element

The http-conf:client element is used to specify the connection properties of an HTTP consumer in a WSDL document. The http-conf:client element is a child of the WSDL port element. It has the same attributes as the client element used in the configuration file. The attributes are described in Table 12.2, “HTTP Consumer Configuration Attributes”.

Example

Example 12.8, “WSDL to Configure an HTTP Consumer Endpoint” shows a WSDL fragment that configures an HTTP consumer endpoint to specify that it does not interact with caches.

Example 12.8. WSDL to Configure an HTTP Consumer Endpoint

<service ... >
  <port ... >
    <soap:address ... />
    <http-conf:client CacheControl="no-cache" />
  </port>
</service>

12.2.4. Consumer Cache Control Directives

Table 12.3, “http-conf:client Cache Control Directives” lists the cache control directives supported by an HTTP consumer.

Table 12.3. http-conf:client Cache Control Directives
DirectiveBehavior

no-cache

Caches cannot use a particular response to satisfy subsequent requests without first revalidating that response with the server. If specific response header fields are specified with this value, the restriction applies only to those header fields within the response. If no response header fields are specified, the restriction applies to the entire response.

no-store

Caches must not store either any part of a response or any part of the request that invoked it.

max-age

The consumer can accept a response whose age is no greater than the specified time in seconds.

max-stale

The consumer can accept a response that has exceeded its expiration time. If a value is assigned to max-stale, it represents the number of seconds beyond the expiration time of a response up to which the consumer can still accept that response. If no value is assigned, the consumer can accept a stale response of any age.

min-fresh

The consumer wants a response that is still fresh for at least the specified number of seconds indicated.

no-transform

Caches must not modify media type or location of the content in a response between a provider and a consumer.

only-if-cached

Caches should return only responses that are currently stored in the cache, and not responses that need to be reloaded or revalidated.

cache-extension

Specifies additional extensions to the other cache directives. Extensions can be informational or behavioral. An extended directive is specified in the context of a standard directive, so that applications not understanding the extended directive can adhere to the behavior mandated by the standard directive.

12.3. Configuring a Service Provider

12.3.1. Mechanisms for a HTTP Service Provider

HTTP service provider endpoints can specify a number of HTTP connection attributes including if it will honor keep alive requests, how it interacts with caches, and how tolerant it is of errors in communicating with a consumer.

A service provider endpoint can be configured using two mechanisms:

12.3.2. Using Configuration

Namespace

The elements used to configure an HTTP provider endpoint are defined in the namespace http://cxf.apache.org/transports/http/configuration. It is commonly referred to using the prefix http-conf. In order to use the HTTP configuration elements you must add the lines shown in Example 12.9, “HTTP Provider Configuration Namespace” to the beans element of your endpoint’s configuration file. In addition, you must add the configuration elements' namespace to the xsi:schemaLocation attribute.

Example 12.9. HTTP Provider Configuration Namespace

<beans ...
       xmlns:http-conf="http://cxf.apache.org/transports/http/configuration"
       ...
       xsi:schemaLocation="...
                           http://cxf.apache.org/transports/http/configuration
                              http://cxf.apache.org/schemas/configuration/http-conf.xsd
                          ...">
Undertow runtime or Netty runtime

You can use the elements from the http-conf namespace to configure either the Undertow runtime or the Netty runtime.

The destination element

You configure an HTTP service provider endpoint using the http-conf:destination element and its children. The http-conf:destination element takes a single attribute, name, that specifies the WSDL port element that corresponds to the endpoint. The value for the name attribute takes the form portQName`.http-destination`. Example 12.10, “http-conf:destination Element” shows the http-conf:destination element that is used to add configuration for an endpoint that is specified by the WSDL fragment <port binding="widgetSOAPBinding" name="widgetSOAPPort> when the endpoint’s target namespace is http://widgets.widgetvendor.net.

Example 12.10. http-conf:destination Element

...
  <http-conf:destination name="{http://widgets/widgetvendor.net}widgetSOAPPort.http-destination">
    ...
  </http-conf:destination>
...

The http-conf:destination element has a number of child elements that specify configuration information. They are described in Table 12.4, “Elements Used to Configure an HTTP Service Provider Endpoint”.

Table 12.4. Elements Used to Configure an HTTP Service Provider Endpoint
ElementDescription

http-conf:server

Specifies the HTTP connection properties. See the section called “The server element”.

http-conf:contextMatchStrategy

Specifies the parameters that configure the context match strategy for processing HTTP requests.

http-conf:fixedParameterOrder

Specifies whether the parameter order of an HTTP request handled by this destination is fixed.

The server element

The http-conf:server element is used to configure the properties of a service provider endpoint’s HTTP connection. Its attributes, described in Table 12.5, “HTTP Service Provider Configuration Attributes”, specify the connection’s properties.

Table 12.5. HTTP Service Provider Configuration Attributes
AttributeDescription

ReceiveTimeout

Sets the length of time, in milliseconds, the service provider attempts to receive a request before the connection times out. The default is 30000.

0 specifies that the provider will not timeout.

SuppressClientSendErrors

Specifies whether exceptions are to be thrown when an error is encountered on receiving a request. The default is false; exceptions are thrown on encountering errors.

SuppressClientReceiveErrors

Specifies whether exceptions are to be thrown when an error is encountered on sending a response to a consumer. The default is false; exceptions are thrown on encountering errors.

HonorKeepAlive

Specifies whether the service provider honors requests for a connection to remain open after a response has been sent. The default is false; keep-alive requests are ignored.

RedirectURL

Specifies the URL to which the client request should be redirected if the URL specified in the client request is no longer appropriate for the requested resource. In this case, if a status code is not automatically set in the first line of the server response, the status code is set to 302 and the status description is set to Object Moved. The value is used as the value of the HTTP RedirectURL property.

CacheControl

Specifies directives about the behavior that must be adhered to by caches involved in the chain comprising a response from a service provider to a consumer. See Section 12.3.4, “Service Provider Cache Control Directives”.

ContentLocation

Sets the URL where the resource being sent in a response is located.

ContentType

Specifies the media type of the information being sent in a response. Media types are specified using multipurpose internet mail extensions (MIME) types. The value is used as the value of the HTTP ContentType location.

ContentEncoding

Specifies any additional content encodings that have been applied to the information being sent by the service provider. Content encoding labels are regulated by the Internet Assigned Numbers Authority (IANA). Possible content encoding values include zip, gzip, compress, deflate, and identity. This value is used as the value of the HTTP ContentEncoding property.

The primary use of content encodings is to allow documents to be compressed using some encoding mechanism, such as zip or gzip. Apache CXF performs no validation on content codings. It is the user’s responsibility to ensure that a specified content coding is supported at application level.

ServerType

Specifies what type of server is sending the response. Values take the form program-name/version; for example, Apache/1.2.5.

Example

Example 12.11, “HTTP Service Provider Endpoint Configuration” shows the configuration for an HTTP service provider endpoint that honors keep-alive requests and suppresses all communication errors.

Example 12.11. HTTP Service Provider Endpoint Configuration

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:http-conf="http://cxf.apache.org/transports/http/configuration"
       xsi:schemaLocation="http://cxf.apache.org/transports/http/configuration
                             http://cxf.apache.org/schemas/configuration/http-conf.xsd
                           http://www.springframework.org/schema/beans
                             http://www.springframework.org/schema/beans/spring-beans.xsd">

  <http-conf:destination name="{http://apache.org/hello_world_soap_http}SoapPort.http-destination">
    <http-conf:server SuppressClientSendErrors="true"
                      SuppressClientReceiveErrors="true"
                      HonorKeepAlive="true" />
  </http-conf:destination>
</beans>

12.3.3. Using WSDL

Namespace

The WSDL extension elements used to configure an HTTP provider endpoint are defined in the namespace http://cxf.apache.org/transports/http/configuration. It is commonly referred to using the prefix http-conf. To use the HTTP configuration elements you must add the line shown in Example 12.12, “HTTP Provider WSDL Element’s Namespace” to the definitions element of your endpoint’s WSDL document.

Example 12.12. HTTP Provider WSDL Element’s Namespace

<definitions ...
       xmlns:http-conf="http://cxf.apache.org/transports/http/configuration"
Undertow runtime or Netty runtime

You can use the elements from the http-conf namespace to configure either the Undertow runtime or the Netty runtime.

The server element

The http-conf:server element is used to specify the connection properties of an HTTP service provider in a WSDL document. The http-conf:server element is a child of the WSDL port element. It has the same attributes as the server element used in the configuration file. The attributes are described in Table 12.5, “HTTP Service Provider Configuration Attributes”.

Example

Example 12.13, “WSDL to Configure an HTTP Service Provider Endpoint” shows a WSDL fragment that configures an HTTP service provider endpoint specifying that it will not interact with caches.

Example 12.13. WSDL to Configure an HTTP Service Provider Endpoint

<service ... >
  <port ... >
    <soap:address ... />
    <http-conf:server CacheControl="no-cache" />
  </port>
</service>

12.3.4. Service Provider Cache Control Directives

Table 12.6, “http-conf:server Cache Control Directives” lists the cache control directives supported by an HTTP service provider.

Table 12.6. http-conf:server Cache Control Directives
DirectiveBehavior

no-cache

Caches cannot use a particular response to satisfy subsequent requests without first revalidating that response with the server. If specific response header fields are specified with this value, the restriction applies only to those header fields within the response. If no response header fields are specified, the restriction applies to the entire response.

public

Any cache can store the response.

private

Public (shared) caches cannot store the response because the response is intended for a single user. If specific response header fields are specified with this value, the restriction applies only to those header fields within the response. If no response header fields are specified, the restriction applies to the entire response.

no-store

Caches must not store any part of the response or any part of the request that invoked it.

no-transform

Caches must not modify the media type or location of the content in a response between a server and a client.

must-revalidate

Caches must revalidate expired entries that relate to a response before that entry can be used in a subsequent response.

proxy-revalidate

Does the same as must-revalidate, except that it can only be enforced on shared caches and is ignored by private unshared caches. When using this directive, the public cache directive must also be used.

max-age

Clients can accept a response whose age is no greater that the specified number of seconds.

s-max-age

Does the same as max-age, except that it can only be enforced on shared caches and is ignored by private unshared caches. The age specified by s-max-age overrides the age specified by max-age. When using this directive, the proxy-revalidate directive must also be used.

cache-extension

Specifies additional extensions to the other cache directives. Extensions can be informational or behavioral. An extended directive is specified in the context of a standard directive, so that applications not understanding the extended directive can adhere to the behavior mandated by the standard directive.

12.4. Configuring the Undertow Runtime

Overview

The Undertow runtime is used by HTTP service providers and HTTP consumers using a decoupled endpoint. The runtime’s thread pool can be configured, and you can also set a number of the security settings for an HTTP service provider through the Undertow runtime.

Maven dependency

If you use Apache Maven as your build system, you can add the Undertow runtime to your project by including the following dependency in your project’s pom.xml file:

<dependency>
    <groupId>org.apache.cxf</groupId>
    <artifactId>cxf-rt-transports-http-undertow</artifactId>
    <version>${cxf-version}</version>
</dependency>

Namespace

The elements used to configure the Undertow runtime are defined in the namespace http://cxf.apache.org/transports/http-undertow/configuration. In order to use the Undertow configuration elements you must add the lines shown in Example 12.14, “Undertow Runtime Configuration Namespace” to the beans element of your endpoint’s configuration file. In this example, the namespace is assigned the prefix httpu. In addition, you must add the configuration element’s namespace to the xsi:schemaLocation attribute.

Example 12.14. Undertow Runtime Configuration Namespace

<beans ...
       xmlns:httpu="http://cxf.apache.org/transports/http-undertow/configuration"
       ...
       xsi:schemaLocation="...
                           http://cxf.apache.org/transports/http-undertow/configuration
                              http://cxf.apache.org/schemas/configuration/http-undertow.xsd
                          ...">

The engine-factory element

The httpu:engine-factory element is the root element used to configure the Undertow runtime used by an application. It has a single required attribute, bus, whose value is the name of the Bus that manages the Undertow instances being configured.

Note

The value is typically cxf which is the name of the default Bus instance.

The http:engine-factory element has three children that contain the information used to configure the HTTP ports instantiated by the Undertow runtime factory. The children are described in Table 12.7, “Elements for Configuring a Undertow Runtime Factory”.

Table 12.7. Elements for Configuring a Undertow Runtime Factory
ElementDescription

httpu:engine

Specifies the configuration for a particular Undertow runtime instance. See the section called “The engine element”.

httpu:identifiedTLSServerParameters

Specifies a reusable set of properties for securing an HTTP service provider. It has a single attribute, id, that specifies a unique identifier by which the property set can be referred.

httpu:identifiedThreadingParameters

Specifies a reusable set of properties for controlling a Undertow instance’s thread pool. It has a single attribute, id, that specifies a unique identifier by which the property set can be referred.

See the section called “Configuring the thread pool”.

The engine element

The httpu:engine element is used to configure specific instances of the Undertow runtime. It has a single attribute, port, that specifies the number of the port being managed by the Undertow instance.

Note

You can specify a value of 0 for the port attribute. Any threading properties specified in an httpu:engine element with its port attribute set to 0 are used as the configuration for all Undertow listeners that are not explicitly configured.

Each httpu:engine element can have two children: one for configuring security properties and one for configuring the Undertow instance’s thread pool. For each type of configuration you can either directly provide the configuration information or you can provide a reference to a set of configuration properties defined in the parent httpu:engine-factory element.

The child elements used to provide the configuration properties are described in Table 12.8, “Elements for Configuring an Undertow Runtime Instance”.

Table 12.8. Elements for Configuring an Undertow Runtime Instance
ElementDescription

httpu:tlsServerParameters

Specifies a set of properties for configuring the security used for the specific Undertow instance.

httpu:tlsServerParametersRef

Refers to a set of security properties defined by a identifiedTLSServerParameters element. The id attribute provides the id of the referred identifiedTLSServerParameters element.

httpu:threadingParameters

Specifies the size of the thread pool used by the specific Undertow instance. See the section called “Configuring the thread pool”.

httpu:threadingParametersRef

Refers to a set of properties defined by a identifiedThreadingParameters element. The id attribute provides the id of the referred identifiedThreadingParameters element.

Configuring the thread pool

You can configure the size of an Undertow instance’s thread pool by either:

  • Specifying the size of the thread pool using a identifiedThreadingParameters element in the engine-factory element. You then refer to the element using a threadingParametersRef element.
  • Specifying the size of the of the thread pool directly using a threadingParameters element.

The threadingParameters has two attributes to specify the size of a thread pool. The attributes are described in Table 12.9, “Attributes for Configuring an Undertow Thread Pool”.

Note

The httpu:identifiedThreadingParameters element has a single child threadingParameters element.

Table 12.9. Attributes for Configuring an Undertow Thread Pool
AttributeDescription

workerIOThreads

Specifies the number of I/O threads to be created for the worker. If not specified, the dafult value will be chosen. The default value is one I/O thread per CPU core.

minThreads

Specifies the minimum number of threads available to the Undertow instance for processing requests.

maxThreads

Specifies the maximum number of threads available to the Undertow instance for processing requests.

Example

Example 12.15, “Configuring an Undertow Instance” shows a configuration fragment that configures an Undertow instance on port number 9001.

Example 12.15. Configuring an Undertow Instance

<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:sec="http://cxf.apache.org/configuration/security"
  xmlns:http="http://cxf.apache.org/transports/http/configuration"
  xmlns:httpu="http://cxf.apache.org/transports/http-undertow/configuration"
  xmlns:jaxws="http://java.sun.com/xml/ns/jaxws"
  xsi:schemaLocation="http://cxf.apache.org/configuration/security
  		      http://cxf.apache.org/schemas/configuration/security.xsd
            http://cxf.apache.org/transports/http/configuration
            http://cxf.apache.org/schemas/configuration/http-conf.xsd
            http://cxf.apache.org/transports/http-undertow/configuration
            http://cxf.apache.org/schemas/configuration/http-undertow.xsd
            http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans-2.0.xsd">
  ...

  <httpu:engine-factory bus="cxf">
    <httpu:identifiedTLSServerParameters id="secure">
      <sec:keyManagers keyPassword="password">
        <sec:keyStore type="JKS" password="password"
                      file="certs/cherry.jks"/>
      </sec:keyManagers>
    </httpu:identifiedTLSServerParameters>

    <httpu:engine port="9001">
      <httpu:tlsServerParametersRef id="secure" />
      <httpu:threadingParameters minThreads="5"
                                 maxThreads="15" />
    </httpu:engine>
  </httpu:engine-factory>
 </beans>

12.5. Configuring the Netty Runtime

Overview

The Netty runtime is used by HTTP service providers and HTTP consumers using a decoupled endpoint. The runtime’s thread pool can be configured, and you can also set a number of the security settings for an HTTP service provider through the Netty runtime.

Maven dependencies

If you use Apache Maven as your build system, you can add the server-side implementation of the Netty runtime (for defining Web service endpoints) to your project by including the following dependency in your project’s pom.xml file:

<dependency>
    <groupId>org.apache.cxf</groupId>
    <artifactId>cxf-rt-transports-http-netty-server</artifactId>
    <version>${cxf-version}</version>
</dependency>

You can add the client-side implementation of the Netty runtime (for defining Web service clients) to your project by including the following dependency in your project’s pom.xml file:

<dependency>
    <groupId>org.apache.cxf</groupId>
    <artifactId>cxf-rt-transports-http-netty-client</artifactId>
    <version>${cxf-version}</version>
</dependency>

Namespace

The elements used to configure the Netty runtime are defined in the namespace http://cxf.apache.org/transports/http-netty-server/configuration. It is commonly referred to using the prefix httpn. In order to use the Netty configuration elements you must add the lines shown in Example 12.16, “Netty Runtime Configuration Namespace” to the beans element of your endpoint’s configuration file. In addition, you must add the configuration elements' namespace to the xsi:schemaLocation attribute.

Example 12.16. Netty Runtime Configuration Namespace

<beans ...
       xmlns:httpn="http://cxf.apache.org/transports/http-netty-server/configuration"
       ...
       xsi:schemaLocation="...
               http://cxf.apache.org/transports/http-netty-server/configuration
            http://cxf.apache.org/schemas/configuration/http-netty-server.xsd
               ...">

The engine-factory element

The httpn:engine-factory element is the root element used to configure the Netty runtime used by an application. It has a single required attribute, bus, whose value is the name of the Bus that manages the Netty instances being configured.

Note

The value is typically cxf, which is the name of the default Bus instance.

The httpn:engine-factory element has three children that contain the information used to configure the HTTP ports instantiated by the Netty runtime factory. The children are described in Table 12.10, “Elements for Configuring a Netty Runtime Factory”.

Table 12.10. Elements for Configuring a Netty Runtime Factory
ElementDescription

httpn:engine

Specifies the configuration for a particular Netty runtime instance. See the section called “The engine element”.

httpn:identifiedTLSServerParameters

Specifies a reusable set of properties for securing an HTTP service provider. It has a single attribute, id, that specifies a unique identifier by which the property set can be referred.

httpn:identifiedThreadingParameters

Specifies a reusable set of properties for controlling a Netty instance’s thread pool. It has a single attribute, id, that specifies a unique identifier by which the property set can be referred.

See the section called “Configuring the thread pool”.

The engine element

The httpn:engine element is used to configure specific instances of the Netty runtime. Table 12.11, “Attributes for Configuring a Netty Runtime Instance” shows the attributes supported by the httpn:engine element.

Table 12.11. Attributes for Configuring a Netty Runtime Instance
AttributeDescription

port

Specifies the port used by the Netty HTTP server instance. You can specify a value of 0 for the port attribute. Any threading properties specified in an engine element with its port attribute set to 0 are used as the configuration for all Netty listeners that are not explicitly configured.

host

Specifies the listen address used by the Netty HTTP server instance. The value can be a hostname or an IP address. If not specified, Netty HTTP server will listen on all local addresses.

readIdleTime

Specifies the maximum read idle time for a Netty connection. The timer is reset whenever there are any read actions on the underlying stream.

writeIdleTime

Specifies the maximum write idle time for a Netty connection. The timer is reset whenever there are any write actions on the underlying stream.

maxChunkContentSize

Specifies the maximum aggregated content size for a Netty connection. The default value is 10MB.

A httpn:engine element has one child element for configuring security properties and one child element for configuring the Netty instance’s thread pool. For each type of configuration you can either directly provide the configuration information or you can provide a reference to a set of configuration properties defined in the parent httpn:engine-factory element.

The supported child elements of httpn:engine are shown in Table 12.12, “Elements for Configuring a Netty Runtime Instance”.

Table 12.12. Elements for Configuring a Netty Runtime Instance
ElementDescription

httpn:tlsServerParameters

Specifies a set of properties for configuring the security used for the specific Netty instance.

httpn:tlsServerParametersRef

Refers to a set of security properties defined by a identifiedTLSServerParameters element. The id attribute provides the id of the referred identifiedTLSServerParameters element.

httpn:threadingParameters

Specifies the size of the thread pool used by the specific Netty instance. See the section called “Configuring the thread pool”.

httpn:threadingParametersRef

Refers to a set of properties defined by a identifiedThreadingParameters element. The id attribute provides the id of the referred identifiedThreadingParameters element.

httpn:sessionSupport

When true, enables support for HTTP sessions. Default is false.

httpn:reuseAddress

Specifies a boolean value to set the ReuseAddress TCP socket option. Default is false.

Configuring the thread pool

You can configure the size of a Netty instance’s thread pool by either:

  • Specifying the size of the thread pool using a identifiedThreadingParameters element in the engine-factory element. You then refer to the element using a threadingParametersRef element.
  • Specifying the size of the of the thread pool directly using a threadingParameters element.

The threadingParameters element has one attribute to specify the size of a thread pool, as described in Table 12.13, “Attributes for Configuring a Netty Thread Pool”.

Note

The httpn:identifiedThreadingParameters element has a single child threadingParameters element.

Table 12.13. Attributes for Configuring a Netty Thread Pool
AttributeDescription

threadPoolSize

Specifies the number of threads available to the Netty instance for processing requests.

Example

Example 12.17, “Configuring a Netty Instance” shows a configuration fragment that configures a variety of Netty ports.

Example 12.17. Configuring a Netty Instance

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:beans="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:h="http://cxf.apache.org/transports/http/configuration"
       xmlns:httpn="http://cxf.apache.org/transports/http-netty-server/configuration"
       xmlns:sec="http://cxf.apache.org/configuration/security"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans
            http://www.springframework.org/schema/beans/spring-beans.xsd
        http://cxf.apache.org/configuration/security
            http://cxf.apache.org/schemas/configuration/security.xsd
        http://cxf.apache.org/transports/http/configuration
            http://cxf.apache.org/schemas/configuration/http-conf.xsd
        http://cxf.apache.org/transports/http-netty-server/configuration
            http://cxf.apache.org/schemas/configuration/http-netty-server.xsd"
>
    ...
    <httpn:engine-factory bus="cxf">
       <httpn:identifiedTLSServerParameters id="sample1">
         <httpn:tlsServerParameters jsseProvider="SUN" secureSocketProtocol="TLS">
            <sec:clientAuthentication want="false" required="false"/>
         </httpn:tlsServerParameters>
       </httpn:identifiedTLSServerParameters>

       <httpn:identifiedThreadingParameters id="sampleThreading1">
          <httpn:threadingParameters threadPoolSize="120"/>
       </httpn:identifiedThreadingParameters>

       <httpn:engine port="9000" readIdleTime="30000" writeIdleTime="90000">
          <httpn:threadingParametersRef id="sampleThreading1"/>
       </httpn:engine>

       <httpn:engine port="0">
          <httpn:threadingParameters threadPoolSize="400"/>
       </httpn:engine>

       <httpn:engine port="9001" readIdleTime="40000" maxChunkContentSize="10000">
         <httpn:threadingParameters threadPoolSize="99" />
         <httpn:sessionSupport>true</httpn:sessionSupport>
       </httpn:engine>

       <httpn:engine port="9002">
         <httpn:tlsServerParameters>
           <sec:clientAuthentication want="true" required="true"/>
         </httpn:tlsServerParameters>
       </httpn:engine>

       <httpn:engine port="9003">
          <httpn:tlsServerParametersRef id="sample1"/>
       </httpn:engine>

    </httpn:engine-factory>
</beans>

12.6. Using the HTTP Transport in Decoupled Mode

Overview

In normal HTTP request/response scenarios, the request and the response are sent using the same HTTP connection. The service provider processes the request and responds with a response containing the appropriate HTTP status code and the contents of the response. In the case of a successful request, the HTTP status code is set to 200.

In some instances, such as when using WS-RM or when requests take an extended period of time to execute, it makes sense to decouple the request and response message. In this case the service providers sends the consumer a 202 Accepted response to the consumer over the back-channel of the HTTP connection on which the request was received. It then processes the request and sends the response back to the consumer using a new decoupled server→client HTTP connection. The consumer runtime receives the incoming response and correlates it with the appropriate request before returning to the application code.

Configuring decoupled interactions

Using the HTTP transport in decoupled mode requires that you do the following:

  1. Configure the consumer to use WS-Addressing.

    See the section called “Configuring an endpoint to use WS-Addressing”.

  2. Configure the consumer to use a decoupled endpoint.

    See the section called “Configuring the consumer”.

  3. Configure any service providers that the consumer interacts with to use WS-Addressing.

    See the section called “Configuring an endpoint to use WS-Addressing”.

Configuring an endpoint to use WS-Addressing

Specify that the consumer and any service provider with which the consumer interacts use WS-Addressing.

You can specify that an endpoint uses WS-Addressing in one of two ways:

  • Adding the wswa:UsingAddressing element to the endpoint’s WSDL port element as shown in Example 12.18, “Activating WS-Addressing using WSDL”.

    Example 12.18. Activating WS-Addressing using WSDL

    ...
    <service name="WidgetSOAPService">
      <port name="WidgetSOAPPort" binding="tns:WidgetSOAPBinding">
        <soap:address="http://widgetvendor.net/widgetSeller" />
        <wswa:UsingAddressing xmlns:wswa="http://www.w3.org/2005/02/addressing/wsdl"/>
      </port>
    </service>
    ...
  • Adding the WS-Addressing policy to the endpoint’s WSDL port element as shown in Example 12.19, “Activating WS-Addressing using a Policy”.

    Example 12.19. Activating WS-Addressing using a Policy

    ...
    <service name="WidgetSOAPService">
      <port name="WidgetSOAPPort" binding="tns:WidgetSOAPBinding">
        <soap:address="http://widgetvendor.net/widgetSeller" />
        <wsp:Policy xmlns:wsp="http://www.w3.org/2006/07/ws-policy"> <wsam:Addressing xmlns:wsam="http://www.w3.org/2007/02/addressing/metadata"> <wsp:Policy/> </wsam:Addressing> </wsp:Policy>
      </port>
    </service>
    ...
Note

The WS-Addressing policy supersedes the wswa:UsingAddressing WSDL element.

Configuring the consumer

Configure the consumer endpoint to use a decoupled endpoint using the DecoupledEndpoint attribute of the http-conf:conduit element.

Example 12.20, “Configuring a Consumer to Use a Decoupled HTTP Endpoint” shows the configuration for setting up the endpoint defined in Example 12.18, “Activating WS-Addressing using WSDL” to use use a decoupled endpoint. The consumer now receives all responses at http://widgetvendor.net/widgetSellerInbox.

Example 12.20. Configuring a Consumer to Use a Decoupled HTTP Endpoint

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:http="http://cxf.apache.org/transports/http/configuration"
       xsi:schemaLocation="http://cxf.apache.org/transports/http/configuration
                             http://cxf.apache.org/schemas/configuration/http-conf.xsd
                           http://www.springframework.org/schema/beans
                             http://www.springframework.org/schema/beans/spring-beans.xsd">

  <http:conduit name="{http://widgetvendor.net/services}WidgetSOAPPort.http-conduit">
    <http:client DecoupledEndpoint="http://widgetvendor.net:9999/decoupled_endpoint" />
  </http:conduit>
</beans>

How messages are processed

Using the HTTP transport in decoupled mode adds extra layers of complexity to the processing of HTTP messages. While the added complexity is transparent to the implementation level code in an application, it might be important to understand what happens for debugging reasons.

Figure 12.1, “Message Flow in for a Decoupled HTTP Transport” shows the flow of messages when using HTTP in decoupled mode.

Figure 12.1. Message Flow in for a Decoupled HTTP Transport

There are fifteen steps in a decoupled message exchange.

A request starts the following process:

  1. The consumer implementation invokes an operation and a request message is generated.
  2. The WS-Addressing layer adds the WS-A headers to the message.

    When a decoupled endpoint is specified in the consumer’s configuration, the address of the decoupled endpoint is placed in the WS-A ReplyTo header.

  3. The message is sent to the service provider.
  4. The service provider receives the message.
  5. The request message from the consumer is dispatched to the provider’s WS-A layer.
  6. Because the WS-A ReplyTo header is not set to anonymous, the provider sends back a message with the HTTP status code set to 202, acknowledging that the request has been received.
  7. The HTTP layer sends a 202 Accepted message back to the consumer using the original connection’s back-channel.
  8. The consumer receives the 202 Accepted reply on the back-channel of the HTTP connection used to send the original message.

    When the consumer receives the 202 Accepted reply, the HTTP connection closes.

  9. The request is passed to the service provider’s implementation where the request is processed.
  10. When the response is ready, it is dispatched to the WS-A layer.
  11. The WS-A layer adds the WS-Addressing headers to the response message.
  12. The HTTP transport sends the response to the consumer’s decoupled endpoint.
  13. The consumer’s decoupled endpoint receives the response from the service provider.
  14. The response is dispatched to the consumer’s WS-A layer where it is correlated to the proper request using the WS-A RelatesTo header.
  15. The correlated response is returned to the client implementation and the invoking call is unblocked.

Chapter 13. Using SOAP Over JMS

Abstract

Apache CXF implements the W3C standard SOAP/JMS transport. This standard is intended to provide a more robust alternative to SOAP/HTTP services. Apache CXF applications using this transport should be able to interoperate with applications that also implement the SOAP/JMS standard. The transport is configured directly in an endpoint’s WSDL.

NOTE: Support for the JMS 1.0.2 APIs has been removed in CXF 3.0. If you are using RedHat JBoss Fuse 6.2 or higher (includes CXF 3.0), your JMS provider must support the JMS 1.1 APIs.

13.1. Basic configuration

Overview

The SOAP over JMS protocol is defined by the World Wide Web Consortium(W3C) as a way of providing a more reliable transport layer to the customary SOAP/HTTP protocol used by most services. The Apache CXF implementation is fully compliant with the specification and should be compatible with any framework that is also compliant.

This transport uses JNDI to find the JMS destinations. When an operation is invoked, the request is packaged as a SOAP message and sent in the body of a JMS message to the specified destination.

To use the SOAP/JMS transport:

  1. Specify that the transport type is SOAP/JMS.
  2. Specify the target destination using a JMS URI.
  3. Optionally, configure the JNDI connection.
  4. Optionally, add additional JMS configuration.

Specifying the JMS transport type

You configure a SOAP binding to use the JMS transport when specifying the WSDL binding. You set the soap:binding element’s transport attribute to http://www.w3.org/2010/soapjms/. Example 13.1, “SOAP over JMS binding specification” shows a WSDL binding that uses SOAP/JMS.

Example 13.1. SOAP over JMS binding specification

<wsdl:binding ... >
  <soap:binding style="document"
                transport="http://www.w3.org/2010/soapjms/" />
  ...
</wsdl:binding>

Specifying the target destination

You specify the address of the JMS target destination when specifying the WSDL port for the endpoint. The address specification for a SOAP/JMS endpoint uses the same soap:address element and attribute as a SOAP/HTTP endpoint. The difference is the address specification. JMS endpoints use a JMS URI as defined in the URI Scheme for JMS 1.0. Example 13.2, “JMS URI syntax” shows the syntax for a JMS URI.

Example 13.2. JMS URI syntax

jms:variant:destination?options

Table 13.1, “JMS URI variants” describes the available variants for the JMS URI.

Table 13.1. JMS URI variants
VariantDescription

jndi

Specifies that the destination name is a JNDI queue name. When using this variant, you must provide the configuration for accessing the JNDI provider.

jndi-topic

Specifies that the destination name is a JNDI topic name. When using this variant, you must provide the configuration for accessing the JNDI provider.

queue

Specifies that the destination is a queue name resolved using JMS. The string provided is passed into Session.createQueue() to create a representation of the destination.

topic

Specifies that the destination is a topic name resolved using JMS. The string provided is passed into Session.createTopic() to create a representation of the destination.

The options portion of a JMS URI are used to configure the transport and are discussed in Section 13.2, “JMS URIs”.

Example 13.3, “SOAP/JMS endpoint address” shows the WSDL port entry for a SOAP/JMS endpoint whose target destination is looked up using JNDI.

Example 13.3. SOAP/JMS endpoint address

<wsdl:port ... >
  ...
  <soap:address location="jms:jndi:dynamicQueues/test.cxf.jmstransport.queue" />
</wsdl:port>

Configuring JNDI and the JMS transport

The SOAP/JMS provides several ways to configure the JNDI connection and the JMS transport:

13.2. JMS URIs

Overview

When using SOAP/JMS, a JMS URI is used to specify the endpoint’s target destination. The JMS URI can also be used to configure JMS connection by appending one or more options to the URI. These options are detailed in the IETF standard, URI Scheme for Java Message Service 1.0. They can be used to configure the JNDI system, the reply destination, the delivery mode to use, and other JMS properties.

Syntax

As shown in Example 13.4, “Syntax for JMS URI options”, you can append one or more options to the end of a JMS URI by separating them from the destination’s address with a question mark(?). Multiple options are separated by an ampersand(&). Example 13.4, “Syntax for JMS URI options” shows the syntax for using multiple options in a JMS URI.

Example 13.4. Syntax for JMS URI options

jms:variant:jmsAddress?option1=value1&option2=value2&_optionN_=valueN

JMS properties

Table 13.2, “JMS properties settable as URI options” shows the URI options that affect the JMS transport layer.

Table 13.2. JMS properties settable as URI options
PropertyDefaultDescription

conduitIdSelectorPrefix

 

[Optional] A string value that is prefixed to all correlation IDs that the conduit creates. The selector can use it to listen for replies.

deliveryMode

PERSISTENT

Specifies whether to use JMS PERSISTENT or NON_PERSISTENT message semantics. In the case of PERSISTENT delivery mode, the JMS broker stores messages in persistent storage before acknowledging them; whereas NON_PERSISTENT messages are kept in memory only.

durableSubscriptionClientID

 

[Optional] Specifies the client identifier for the connection. This property is used to associate a connection with a state that the provider maintains on behalf of the client. This enables subsequent subscribers with the same identity to resume the subscription in the state that the preceding subscriber left it.

durableSubscriptionName

 

[Optional] Specifies the name of the subscription.

messageType

byte

Specifies the JMS message type used by CXF. Valid values are:

  • byte
  • text
  • binary

password

 

[Optional] Specifies the password for creating the connection. Appending this property to the URI is discouraged.

priority

4

Specifies the JMS message priority, which ranges from 0 (lowest) to 9 (highest).

receiveTimout

60000

Specifies the time, in milliseconds, the client will wait for a reply when request/reply exchanges are used.

reconnectOnException

true

[Deprecated in CXF 3.0] Specifies whether the transport should reconnect when exceptions occur.

As of 3.0, the transport will always reconnect when an exception occurs.

replyToName

 

[Optional] Specifies the reply destination for queue messages. The reply destination appears in the JMSReplyTo header. Setting this property is recommended for applications that have request-reply semantics because the JMS provider will assign a temporary reply queue if one is not specified.

The value of this property is interpreted according to the variant specified in the JMS URI:

  • jndi variant—the name of the destination queue resolved by JNDI
  • queue variant—the name of the destination queue resolved using JMS

sessionTransacted

false

Specifies the transaction type. Valid values are:

  • true—resource local transactions
  • false—JTA transactions

timeToLive

0

Specifies the time, in milliseconds, after which the JMS provider will discard the message. A value of 0 indicates an infinite lifetime.

topicReplyToName

 

[Optional] Specifies the reply destination for topic messages. The value of this property is interpreted according to the variant specified in the JMS URI:

  • jndi-topic—the name of the destination topic resolved by JNDI
  • topic—the name of the destination topic resolved by JMS

useConduitIdSelector

true

Specifies whether the conduit’s UUID will be used as the prefix for all correlation IDs.

As all conduits are assigned a unique UUID, setting this property to true enables multiple endpoints to share a JMS queue or topic.

username

 

[Optional] Specifies the username to use to create the connection.

JNDI properties

Table 13.3, “JNDI properties settable as URI options” shows the URI options that can be used to configure JNDI for this endpoint.

Table 13.3. JNDI properties settable as URI options
PropertyDescription

jndiConnectionFactoryName

Specifies the JNDI name of the JMS connection factory.

jndiInitialContextFactory

Specifies the fully qualified Java class name of the JNDI provider (which must be of javax.jms.InitialContextFactory type). Equivalent to setting the java.naming.factory.initial Java system property.

jndiTransactionManagerName

Specifies the name of the JTA transaction manager that will be searched for in Spring, Blueprint, or JNDI. If a transaction manager is found, JTA transactions will be enabled. See the sessionTransacted JMS property.

jndiURL

Specifies the URL that initializes the JNDI provider. Equivalent to setting the java.naming.provider.url Java system property.

Additional JNDI properties

The properties, java.naming.factory.initial and java.naming.provider.url, are standard properties, which are required to initialize any JNDI provider. Sometimes, however, a JNDI provider might support custom properties in addition to the standard ones. In this case, you can set an arbitrary JNDI property by setting a URI option of the form jndi-PropertyName.

For example, if you were using SUN’s LDAP implementation of JNDI, you could set the JNDI property, java.naming.factory.control, in a JMS URI as shown in Example 13.5, “Setting a JNDI property in a JMS URI”.

Example 13.5. Setting a JNDI property in a JMS URI

jms:queue:FOO.BAR?jndi-java.naming.factory.control=com.sun.jndi.ldap.ResponseControlFactory

Example

If the JMS provider is not already configured, it is possible to provide the requisite JNDI configuration details in the URI using options (see Table 13.3, “JNDI properties settable as URI options”). For example, to configure an endpoint to use the Apache ActiveMQ JMS provider and connect to the queue called test.cxf.jmstransport.queue, use the URI shown in Example 13.6, “JMS URI that configures a JNDI connection”.

Example 13.6. JMS URI that configures a JNDI connection

jms:jndi:dynamicQueues/test.cxf.jmstransport.queue
?jndiInitialContextFactory=org.apache.activemq.jndi.ActiveMQInitialContextFactory
&jndiConnectionFactoryName=ConnectionFactory
&jndiURL=tcp://localhost:61616

Publishing a service

The JAX-WS standard publish() method cannot be used to publish a SOAP/JMS service. Instead, you must use the Apache CXF’s JaxWsServerFactoryBean class as shown in Example 13.7, “Publishing a SOAP/JMS service”.

Example 13.7. Publishing a SOAP/JMS service

String address = "jms:jndi:dynamicQueues/test.cxf.jmstransport.queue3"
    + "?jndiInitialContextFactory"
    + "=org.apache.activemq.jndi.ActiveMQInitialContextFactory"
    + "&jndiConnectionFactoryName=ConnectionFactory"
    + "&jndiURL=tcp://localhost:61500";
Hello implementor = new HelloImpl();
JaxWsServerFactoryBean svrFactory = new JaxWsServerFactoryBean();
svrFactory.setServiceClass(Hello.class);
svrFactory.setAddress(address);
svrFactory.setTransportId(JMSSpecConstants.SOAP_JMS_SPECIFICIATION_TRANSPORTID);
svrFactory.setServiceBean(implementor);
svrFactory.create();

The code in Example 13.7, “Publishing a SOAP/JMS service” does the following:

Creates the JMS URI representing t he endpoint’s address.

Instantiates a JaxWsServerFactoryBean to publish the service.

Sets the address field of the factory bean with the JMS URI of the service.

Specifies that the service created by the factory will use the SOAP/JMS transport.

Consuming a service

The standard JAX-WS APIs cannot be used to consume a SOAP/JMS service. Instead, you must use the Apache CXF’s JaxWsProxyFactoryBean class as shown in Example 13.8, “Consuming a SOAP/JMS service”.

Example 13.8. Consuming a SOAP/JMS service

// Java
public void invoke() throws Exception {
    String address = "jms:jndi:dynamicQueues/test.cxf.jmstransport.queue3"
        + "?jndiInitialContextFactory"
        + "=org.apache.activemq.jndi.ActiveMQInitialContextFactory"
        + "&jndiConnectionFactoryName=ConnectionFactory&jndiURL=tcp://localhost:61500";
    JaxWsProxyFactoryBean factory = new JaxWsProxyFactoryBean();
    factory.setAddress(address);
    factory.setTransportId(JMSSpecConstants.SOAP_JMS_SPECIFICIATION_TRANSPORTID);
    factory.setServiceClass(Hello.class);
    Hello client = (Hello)factory.create();
    String reply = client.sayHi(" HI");
    System.out.println(reply);
}

The code in Example 13.8, “Consuming a SOAP/JMS service” does the following:

Creates the JMS URI representing t he endpoint’s address.

Instantiates a JaxWsProxyFactoryBean to create the proxy.

Sets the address field of the factory bean with the JMS URI of the service.

Specifies that the proxy created by the factory will use the SOAP/JMS transport.

13.3. WSDL extensions

Overview

You can specify the basic configuration of the JMS transport by inserting WSDL extension elements into the contract, either at binding scope, service scope, or port scope. The WSDL extensions enable you to specify the properties for bootstrapping a JNDI InitialContext, which can then be used to look up JMS destinations. You can also set some properties that affect the behavior of the JMS transport layer.

SOAP/JMS namespace

the SOAP/JMS WSDL extensions are defined in the http://www.w3.org/2010/soapjms/ namespace. To use them in your WSDL contracts add the following setting to the wsdl:definitions element:

<wsdl:definitions ...
    xmlns:soapjms="http://www.w3.org/2010/soapjms/"
  ... >

WSDL extension elements

Table 13.4, “SOAP/JMS WSDL extension elements” shows all of the WSDL extension elements you can use to configure the JMS transport.

Table 13.4. SOAP/JMS WSDL extension elements
ElementDefaultDescription

soapjms:jndiInitialContextFactory

 

Specifies the fully qualified Java class name of the JNDI provider. Equivalent to setting the java.naming.factory.initial Java system property.

soapjms:jndiURL

 

Specifies the URL that initializes the JNDI provider. Equivalent to setting the java.naming.provider.url Java system property.

soapjms:jndiContextParameter

 

Specifies an additional property for creating the JNDI InitialContext. Use the name and value attributes to specify the property.

soapjms:jndiConnectionFactoryName

 

Specifies the JNDI name of the JMS connection factory.

soapjms:deliveryMode

PERSISTENT

Specifies whether to use JMS PERSISTENT or NON_PERSISTENT message semantics. In the case of PERSISTENT delivery mode, the JMS broker stores messages in persistent storage before acknowledging them; whereas NON_PERSISTENT messages are kept in memory only.

soapjms:replyToName

 

[Optional] Specifies the reply destination for queue messages. The reply destination appears in the JMSReplyTo header. Setting this property is recommended for applications that have request-reply semantics because the JMS provider will assign a temporary reply queue if one is not specified.

The value of this property is interpreted according to the variant specified in the JMS URI:

  • jndi variant—the name of the destination queue resolved by JNDI
  • queue variant—the name of the destination queue resolved using JMS

soapjms:priority

4

Specifies the JMS message priority, which ranges from 0 (lowest) to 9 (highest).

soapjms:timeToLive

0

Time, in milliseconds, after which the JMS provider will discard the message. A value of 0 represents an infinite lifetime.

Configuration scopes

The WSDL elements placement in the WSDL contract effect the scope of the configuration changes on the endpoints defined in the contract. The SOAP/JMS WSDL elements can be placed as children of either the wsdl:binding element, the wsdl:service element, or the wsdl:port element. The parent of the SOAP/JMS elements determine which of the following scopes the configuration is placed into.

Binding scope
You can configure the JMS transport at the binding scope by placing extension elements inside the wsdl:binding element. Elements in this scope define the default configuration for all endpoints that use this binding. Any settings in the binding scope can be overridden at the service scope or the port scope.
Service scope
You can configure the JMS transport at the service scope by placing extension elements inside a wsdl:service element. Elements in this scope define the default configuration for all endpoints in this service. Any settings in the service scope can be overridden at the port scope.
Port scope
You can configure the JMS transport at the port scope by placing extension elements inside a wsdl:port element. Elements in the port scope define the configuration for this port. They override the defaults of the same extension elements defined at the service scope or at the binding scope.

Example

Example 13.9, “WSDL contract with SOAP/JMS configuration” shows a WSDL contract for a SOAP/JMS service. It configures the JNDI layer in the binding scope, the message delivery details in the service scope, and the reply destination in the port scope.

Example 13.9. WSDL contract with SOAP/JMS configuration

<wsdl:definitions ...
    xmlns:soapjms="http://www.w3.org/2010/soapjms/"
  ... >
  ...
  <wsdl:binding name="JMSGreeterPortBinding" type="tns:JMSGreeterPortType">
    ...
    <soapjms:jndiInitialContextFactory>
      org.apache.activemq.jndi.ActiveMQInitialContextFactory
    </soapjms:jndiInitialContextFactory>
    <soapjms:jndiURL>tcp://localhost:61616</soapjms:jndiURL>
    <soapjms:jndiConnectionFactoryName>
      ConnectionFactory
    </soapjms:jndiConnectionFactoryName>
    ...
  </wsdl:binding>
  ...
  <wsdl:service name="JMSGreeterService">
    ...
    <soapjms:deliveryMode>NON_PERSISTENT</soapjms:deliveryMode>
    <soapjms:timeToLive>60000</soapjms:timeToLive>
    ...
    <wsdl:port binding="tns:JMSGreeterPortBinding" name="GreeterPort">
      <soap:address location="jms:jndi:dynamicQueues/test.cxf.jmstransport.queue" />
      <soapjms:replyToName>
        dynamicQueues/greeterReply.queue
      </soapjms:replyToName>
      ...
    </wsdl:port>
    ...
  </wsdl:service>
  ...
</wsdl:definitions>

The WSDL in Example 13.9, “WSDL contract with SOAP/JMS configuration” does the following:

Declares the namespace for the SOAP/JMS extensions.

Configures the JNDI connections in the binding scope.

Sets the JMS delivery style to non-persistent and each message to live for one minute.

Specifies the target destination.

Configures the JMS transport so that reply messages are delivered on the greeterReply.queue queue.

Chapter 14. Using Generic JMS

Abstract

Apache CXF provides a generic implementation of a JMS transport. The generic JMS transport is not restricted to using SOAP messages and allows for connecting to any application that uses JMS.

NOTE: Support for the JMS 1.0.2 APIs has been removed in CXF 3.0. If you are using RedHat JBoss Fuse 6.2 or higher (includes CXF 3.0), your JMS provider must support the JMS 1.1 APIs.

14.1. Approaches to Configuring JMS

The Apache CXF generic JMS transport can connect to any JMS provider and work with applications that exchange JMS messages with bodies of either TextMessage or ByteMessage.

There are two ways to enable and configure the JMS transport:

14.2. Using the JMS configuration bean

Overview

To simplify JMS configuration and make it more powerful, Apache CXF uses a single JMS configuration bean to configure JMS endpoints. The bean is implemented by the org.apache.cxf.transport.jms.JMSConfiguration class. It can be used to either configure endpoint’s directly or to configure the JMS conduits and destinations.

Configuration namespace

The JMS configuration bean uses the Spring p-namespace to make the configuration as simple as possible. To use this namespace you need to declare it in the configuration’s root element as shown in Example 14.1, “Declaring the Spring p-namespace”.

Example 14.1. Declaring the Spring p-namespace

<beans ...
  xmlns:p="http://www.springframework.org/schema/p"
  ... >
  ...
</beans>

Specifying the configuration

You specify the JMS configuration by defining a bean of class org.apache.cxf.transport.jms.JMSConfiguration. The properties of the bean provide the configuration settings for the transport.

Important

In CXF 3.0, the JMS transport no longer has a dependency on Spring JMS, so some Spring JMS-related options have been removed.

Table 14.1, “General JMS Configuration Properties” lists properties that are common to both providers and consumers.

Table 14.1. General JMS Configuration Properties
PropertyDefaultDescription

connectionFactory

 

[Required] Specifies a reference to a bean that defines a JMS ConnectionFactory.

wrapInSingleConnectionFactory

true [pre v3.0]

Removed in CXF 3.0

pre CXF 3.0 Specifies whether to wrap the ConnectionFactory with a Spring SingleConnectionFactory.

Enable this property when using a ConnectionFactory that does not pool connections, as it will improve the performance of the JMS transport. This is so because the JMS transport creates a new connection for each message, and the SingleConnectionFactory is needed to cache the connection, so it can be reused.

reconnectOnException

false

Deprecated in CXF 3.0 CXF always reconnects when an exception occurs.

pre CXF 3.0 Specifies whether to create a new connection when an exception occurs.

When wrapping the ConnectionFactory with a Spring SingleConnectionFactory:

  • true — on an exception, create a new connection

    Do not enable this option when using a PooledConnectionFactory, as this option only returns the pooled connection, but does not reconnect.

  • false — on an exception, do not try to reconnect

targetDestination

 

Specifies the JNDI name or provider-specific name of a destination.

replyDestination

 

Specifies the JMS name of the JMS destination where replies are sent. This property allows the use of a user-defined destination for replies. For more details see Section 14.6, “Using a Named Reply Destination”.

destinationResolver

DynamicDestinationResolver

Specifies a reference to a Spring DestinationResolver.

This property allows you to define how destination names are resolved to JMS destinations. Valid values are:

  • DynamicDestinationResolver — resolve destination names using the features of the JMS provider.
  • JndiDestinationResolver — resolve destination names using JNDI.

transactionManager

 

Specifies a reference to a Spring transaction manager. This enables the service to participate in JTA transactions.

taskExecutor

SimpleAsyncTaskExecutor

Removed in CXF 3.0

pre CXF 3.0 Specifies a reference to a Spring TaskExecutor. This is used in listeners to decide how to handle incoming messages.

useJms11

false

Removed in CXF 3.0 CXF 3.0 supports JMS 1.1 features only.

pre CXF 3.0 Specifies whether JMS 1.1 features are used. Valid values are:

  • true — JMS 1.1 features
  • false — JMS 1.0.2 features

messageIdEnabled

true

Removed in CXF 3.0

pre CXF 3.0 Specifies whether the JMS transport wants the JMS broker to provide message IDs. Valid values are:

  • true — broker needs to provide message IDs
  • false — broker need not provide message IDs

    In this case, the endpoint calls its message producer’s setDisableMessageID() method with a value of true. The broker is then given a hint that it need not generate message IDs or add them to the endpoint’s messages. The broker either accepts the hint or ignores it.

messageTimestampEnabled

true

Removed in CXF 3.0

pre CXF 3.0 Specifies whether the JMS transport wants the JMS broker to provide message time stamps. Valid values are:

  • true — broker needs to provide message timestamps
  • false — broker need not provide message timestamps

    In this case, the endpoint calls its message producer’s setDisableMessageTimestamp() method with a value of true. The broker is then given a hint that it need not generate time stamps or add them to the endpoint’s messages. The broker either accepts the hint or ignores it.

cacheLevel

-1 (feature disabled)

Removed in CXF 3.0

pre CXF 3.0 Specifies the level of caching that the JMS listener container may apply. Valid values are:

  • 0 — CACHE_NONE
  • 1 — CACHE_CONNECTION
  • 2 — CACHE_SESSION
  • 3 — CACHE_CONSUMER
  • 4 — CACHE_AUTO

For details, see Class DefaultMessageListenerContainer

pubSubNoLocal

false

Specifies whether to receive your own messages when using topics.

  • true — do not receive your own messages
  • false — receive your own messages

receiveTimeout

60000

Specifies the time, in milliseconds, to wait for response messages.

explicitQosEnabled

false

Specifies whether the QoS settings (such as priority, persistence, time to live) are explicitly set for each message (true) or use the default values (false).

deliveryMode

2

Specifies whether a message is persistent. Valid values are:

  • 1 (NON_PERSISTENT)—messages are kept memory only
  • 2 (PERSISTENT)—messages are persisted to disk

priority

4

Specifies message priority. JMS priority values range from 0 (lowest) to 9 (highest). See your JMS provider’s documentation for details.

timeToLive

0 (indefinitely)

Specifies the time, in milliseconds, before a message that has been sent is discarded.

sessionTransacted

false

Specifies whether JMS transactions are used.

concurrentConsumers

1

Removed in CXF 3.0

pre CXF 3.0 Specifies the minimum number of concurrent consumers for the listener.

maxConcurrentConsumers

1

Removed in CXF 3.0

pre CXF 3.0 Specifies the maximum number of concurrent consumers for the listener.

messageSelector

 

Specifies the string value of the selector used to filter incoming messages. This property enables multiple connections to share a queue. For more information on the syntax used to specify message selectors, see the JMS 1.1 specification.

subscriptionDurable

false

Specifies whether the server uses durable subscriptions.

durableSubscriptionName

 

Specifies the name (string) used to register the durable subscription.

messageType

text

Specifies how the message data will be packaged as a JMS message. Valid values are:

  • text — specifies that the data will be packaged as a TextMessage
  • byte — specifies that the data will be packaged as an array of bytes (byte[])
  • binary — specifies that the data will be packaged as an ByteMessage

pubSubDomain

false

Specifies whether the target destination is a topic or a queue. Valid values are:

  • true — topic
  • false — queue

jmsProviderTibcoEms

false

Specifies whether the JMS provider is Tibco EMS.

When set to true, the principal in the security context is populated from the JMS_TIBCO_SENDER header.

useMessageIDAsCorrelationID

false

Removed in CXF 3.0

Specifies whether JMS will use the message ID to correlate messages.

When set to true, the client sets a generated correlation ID.

maxSuspendedContinuations

-1 (feature disabled)

CXF 3.0 Specifies the maximum number of suspended continuations the JMS destination may have. When the current number exceeds the specified maximum, the JMSListenerContainer is stopped.

reconnectPercentOfMax

70

CXF 3.0 Specifies when to restart the JMSListenerContainer stopped for exceeding maxSuspendedContinuations.

The listener container is restarted when its current number of suspended continuations falls below the value of (maxSuspendedContinuations * reconnectPercentOfMax/100).

As shown in Example 14.2, “JMS configuration bean”, the bean’s properties are specified as attributes to the bean element. They are all declared in the Spring p namespace.

Example 14.2. JMS configuration bean

<bean id="jmsConfig"
      class="org.apache.cxf.transport.jms.JMSConfiguration"
      p:connectionFactory="jmsConnectionFactory"
      p:targetDestination="dynamicQueues/greeter.request.queue"
      p:pubSubDomain="false" />

Applying the configuration to an endpoint

The JMSConfiguration bean can be applied directly to both server and client endpoints using the Apache CXF features mechanism. To do so:

  1. Set the endpoint’s address attribute to jms://.
  2. Add a jaxws:feature element to the endpoint’s configuration.
  3. Add a bean of type org.apache.cxf.transport.jms.JMSConfigFeature to the feature.
  4. Set the bean element’s p:jmsConfig-ref attribute to the ID of the JMSConfiguration bean.

Example 14.3, “Adding JMS configuration to a JAX-WS client” shows a JAX-WS client that uses the JMS configuration from Example 14.2, “JMS configuration bean”.

Example 14.3. Adding JMS configuration to a JAX-WS client

<jaxws:client id="CustomerService"
              xmlns:customer="http://customerservice.example.com/"
              serviceName="customer:CustomerServiceService"
              endpointName="customer:CustomerServiceEndpoint"
              address="jms://"
              serviceClass="com.example.customerservice.CustomerService">
  <jaxws:features>
    <bean xmlns="http://www.springframework.org/schema/beans"
          class="org.apache.cxf.transport.jms.JMSConfigFeature"
          p:jmsConfig-ref="jmsConfig"/>
  </jaxws:features>
</jaxws:client>

Applying the configuration to the transport

The JMSConfiguration bean can be applied to JMS conduits and JMS destinations using the jms:jmsConfig-ref element. The jms:jmsConfig-ref element’s value is the ID of the JMSConfiguration bean.

Example 14.4, “Adding JMS configuration to a JMS conduit” shows a JMS conduit that uses the JMS configuration from Example 14.2, “JMS configuration bean”.

Example 14.4. Adding JMS configuration to a JMS conduit

<jms:conduit name="{http://cxf.apache.org/jms_conf_test}HelloWorldQueueBinMsgPort.jms-conduit">
  ...
  <jms:jmsConfig-ref>jmsConf</jms:jmsConfig-ref>
</jms:conduit>

14.3. Optimizing Client-Side JMS Performance

Overview

Two major settings affect the JMS performance of clients: pooling and synchronous receives.

Pooling

On the client side, CXF creates a new JMS session and JMS producer for each message. This is so because neither session nor producer objects are thread safe. Creating a producer is especially time intensive because it requires communicating with the server.

Pooling connection factories improves performance by caching the connection, session, and producer.

For ActiveMQ, configuring pooling is simple; for example:

import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.activemq.pool.PooledConnectionFactory;

ConnectionFactory cf = new ActiveMQConnectionFactory("tcp://localhost:61616");
PooledConnectionFactory pcf = new PooledConnectionFactory();

//Set expiry timeout because the default (0) prevents reconnection on failure
pcf.setExpiryTimeout(5000);
pcf.setConnectionFactory(cf);

JMSConfiguration jmsConfig = new JMSConfiguration();

jmsConfig.setConnectionFactory(pdf);

For more information on pooling, see "Appendix A Optimizing Performance of JMS Single- and Multiple-Resource Transactions" in the Red Hat JBoss Fuse Transaction Guide

Avoiding synchronous receives

For request/reply exchanges, the JMS transport sends a request and then waits for a reply. Whenever possible, request/reply messaging is implemented asynchronously using a JMS MessageListener.

However, CXF must use a synchronous Consumer.receive() method when it needs to share queues between endpoints. This scenario requires the MessageListener to use a message selector to filter the messages. The message selector must be known in advance, so the MessageListener is opened only once.

Two cases in which the message selector cannot be known in advance should be avoided:

  • When JMSMessageID is used as the JMSCorrelationID

    If the JMS properties useConduitIdSelector and conduitSelectorPrefix are not set on the JMS transport, the client does not set a JMSCorrelationId. This causes the server to use the JMSMessageId of the request message as the JMSCorrelationId. As JMSMessageID cannot be known in advance, the client has to use a synchronous Consumer.receive() method.

    Note that you must use the Consumer.receive() method with IBM JMS endpoints (their default).

  • The user sets the JMStype in the request message and then sets a custom JMSCorrelationID.

    Again, as the custom JMSCorrelationID cannot be known in advance, the client has to use a synchronous Consumer.receive() method.

So the general rule is to avoid using settings that require using a synchronous receive.

14.4. Configuring JMS Transactions

Overview

CXF 3.0 supports both local JMS transactions and JTA transactions on CXF endpoints, when using one-way messaging.

Local transactions

Transactions using local resources roll back the JMS message only when an exception occurs. They do not directly coordinate other resources, such as database transactions.

To set up a local transaction, configure the endpoint as you normally would, and set the property sessionTrasnsacted to true.

Note

For more information on transactions and pooling, see the Red Hat JBoss Fuse Transaction Guide.

JTA transactions

Using JTA transactions, you can coordinate any number of XA resources. If a CXF endpoint is configured for JTA transactions, it starts a transaction before calling the service implementation. The transaction will be committed if no exception occurs. Otherwise, it will be rolled back.

In JTA transactions, a JMS message is consumed and the data written to a database. When an exception occurs, both resources are rolled back, so either the message is consumed and the data is written to the database, or the message is rolled back and the data is not written to the database.

Configuring JTA transactions requires two steps:

  1. Defining a transaction manager

    • bean method

      • Define a transaction manager

        <bean id="transactionManager"
           class="org.apache.geronimo.transaction.manager.GeronimoTransactionManager"/>
      • Set the name of the transaction manager in the JMS URI

        jms:queue:myqueue?jndiTransactionManager=TransactionManager

        This example finds a bean with the ID TransactionManager.

    • OSGi reference method

      • Look up the transaction manager as an OSGi service using Blueprint

        <reference id="TransactionManager" interface="javax.transaction.TransactionManager"/>
      • Set the name of the transaction manager in the JMS URI

        jms:jndi:myqueue?jndiTransactionManager=java:comp/env/TransactionManager

        This example looks up the transaction manager in JNDI.

  2. Configuring a JCA pooled connection factory

    Using Spring to define the JCA pooled connection factory:

    <bean id="xacf" class="org.apache.activemq.ActiveMQXAConnectionFactory">
      <property name="brokerURL" value="tcp://localhost:61616" />
    </bean>
    
    <bean id="ConnectionFactory" class="org.apache.activemq.jms.pool.JcaPooledConnectionFactory">
      <property name="transactionManager" ref="transactionManager" />
      <property name="connectionFactory" ref="xacf" />
    </bean>

    In this example, the first bean defines an ActiveMQ XA connection factory, which is given to a JcaPooledConnectionFactory. The JcaPooledConnectionFactory is then provided as the default bean with id ConnectionFactory.

    Note that the JcaPooledConnectionFactory looks like a normal ConnectionFactory. But when a new connection and session are opened, it checks for an XA transaction and, if found, automatically registers the JMS session as an XA resource. This allows the JMS session to participate in the JMS transaction.

    Important

    Directly setting an XA ConnectionFactory on the JMS transport will not work!

14.5. Using WSDL to configure JMS

14.5.1. JMS WSDL Extension Namespance

The WSDL extensions for defining a JMS endpoint are defined in the namespace http://cxf.apache.org/transports/jms. In order to use the JMS extensions you will need to add the line shown in Example 14.5, “JMS WSDL extension namespace” to the definitions element of your contract.

Example 14.5. JMS WSDL extension namespace

xmlns:jms="http://cxf.apache.org/transports/jms"

14.5.2. Basic JMS configuration

Overview

The JMS address information is provided using the jms:address element and its child, the jms:JMSNamingProperties element. The jms:address element’s attributes specify the information needed to identify the JMS broker and the destination. The jms:JMSNamingProperties element specifies the Java properties used to connect to the JNDI service.

Important

Information specified using the JMS feature will override the information in the endpoint’s WSDL file.

Specifying the JMS address

The basic configuration for a JMS endpoint is done by using a jms:address element as the child of your service’s port element. The jms:address element used in WSDL is identical to the one used in the configuration file. Its attributes are listed in Table 14.2, “JMS endpoint attributes”.

Table 14.2. JMS endpoint attributes
AttributeDescription

destinationStyle

Specifies if the JMS destination is a JMS queue or a JMS topic.

jndiConnectionFactoryName

Specifies the JNDI name bound to the JMS connection factory to use when connecting to the JMS destination.

jmsDestinationName

Specifies the JMS name of the JMS destination to which requests are sent.

jmsReplyDestinationName

Specifies the JMS name of the JMS destinations where replies are sent. This attribute allows you to use a user defined destination for replies. For more details see Section 14.6, “Using a Named Reply Destination”.

jndiDestinationName

Specifies the JNDI name bound to the JMS destination to which requests are sent.

jndiReplyDestinationName

Specifies the JNDI name bound to the JMS destinations where replies are sent. This attribute allows you to use a user defined destination for replies. For more details see Section 14.6, “Using a Named Reply Destination”.

connectionUserName

Specifies the user name to use when connecting to a JMS broker.

connectionPassword

Specifies the password to use when connecting to a JMS broker.

The jms:address WSDL element uses a jms:JMSNamingProperties child element to specify additional information needed to connect to a JNDI provider.

Specifying JNDI properties

To increase interoperability with JMS and JNDI providers, the jms:address element has a child element, jms:JMSNamingProperties, that allows you to specify the values used to populate the properties used when connecting to the JNDI provider. The jms:JMSNamingProperties element has two attributes: name and value. name specifies the name of the property to set. value attribute specifies the value for the specified property. jms:JMSNamingProperties element can also be used for specification of provider specific properties.

The following is a list of common JNDI properties that can be set:

  1. java.naming.factory.initial
  2. java.naming.provider.url
  3. java.naming.factory.object
  4. java.naming.factory.state
  5. java.naming.factory.url.pkgs
  6. java.naming.dns.url
  7. java.naming.authoritative
  8. java.naming.batchsize
  9. java.naming.referral
  10. java.naming.security.protocol
  11. java.naming.security.authentication
  12. java.naming.security.principal
  13. java.naming.security.credentials
  14. java.naming.language
  15. java.naming.applet

For more details on what information to use in these attributes, check your JNDI provider’s documentation and consult the Java API reference material.

Example

Example 14.6, “JMS WSDL port specification” shows an example of a JMS WSDL port specification.

Example 14.6. JMS WSDL port specification

<service name="JMSService">
  <port binding="tns:Greeter_SOAPBinding" name="SoapPort">
    <jms:address jndiConnectionFactoryName="ConnectionFactory"
                 jndiDestinationName="dynamicQueues/test.Celtix.jmstransport" >
      <jms:JMSNamingProperty name="java.naming.factory.initial"
                             value="org.activemq.jndi.ActiveMQInitialContextFactory" />
      <jms:JMSNamingProperty name="java.naming.provider.url"
                             value="tcp://localhost:61616" />
    </jms:address>
  </port>
</service>

14.5.3. JMS client configuration

Overview

JMS consumer endpoints specify the type of messages they use. JMS consumer endpoint can use either a JMS ByteMessage or a JMS TextMessage.

When using an ByteMessage the consumer endpoint uses a byte[] as the method for storing data into and retrieving data from the JMS message body. When messages are sent, the message data, including any formating information, is packaged into a byte[] and placed into the message body before it is placed on the wire. When messages are received, the consumer endpoint will attempt to unmarshall the data stored in the message body as if it were packed in a byte[].

When using a TextMessage, the consumer endpoint uses a string as the method for storing and retrieving data from the message body. When messages are sent, the message information, including any format-specific information, is converted into a string and placed into the JMS message body. When messages are received the consumer endpoint will attempt to unmarshall the data stored in the JMS message body as if it were packed into a string.

When native JMS applications interact with Apache CXF consumers, the JMS application is responsible for interpreting the message and the formatting information. For example, if the Apache CXF contract specifies that the binding used for a JMS endpoint is SOAP, and the messages are packaged as TextMessage, the receiving JMS application will get a text message containing all of the SOAP envelope information.

Specifying the message type

The type of messages accepted by a JMS consumer endpoint is configured using the optional jms:client element. The jms:client element is a child of the WSDL port element and has one attribute:

Table 14.3. JMS Client WSDL Extensions

messageType

Specifies how the message data will be packaged as a JMS message. text specifies that the data will be packaged as a TextMessage. binary specifies that the data will be packaged as an ByteMessage.

Example

Example 14.7, “WSDL for a JMS consumer endpoint” shows the WSDL for configuring a JMS consumer endpoint.

Example 14.7. WSDL for a JMS consumer endpoint

<service name="JMSService">
  <port binding="tns:Greeter_SOAPBinding" name="SoapPort">
    <jms:address jndiConnectionFactoryName="ConnectionFactory"
                 jndiDestinationName="dynamicQueues/test.Celtix.jmstransport" >
      <jms:JMSNamingProperty name="java.naming.factory.initial"
                             value="org.activemq.jndi.ActiveMQInitialContextFactory" />
      <jms:JMSNamingProperty name="java.naming.provider.url"
                             value="tcp://localhost:61616" />
    </jms:address>
    <jms:client messageType="binary" />
  </port>
</service>

14.5.4. JMS provider configuration

Overview

JMS provider endpoints have a number of behaviors that are configurable. These include:

  • how messages are correlated
  • the use of durable subscriptions
  • if the service uses local JMS transactions
  • the message selectors used by the endpoint
Specifying the configuration

Provider endpoint behaviors are configured using the optional jms:server element. The jms:server element is a child of the WSDL wsdl:port element and has the following attributes:

Table 14.4. JMS provider endpoint WSDL extensions
AttributeDescription

useMessageIDAsCorrealationID

Specifies whether JMS will use the message ID to correlate messages. The default is false.

durableSubscriberName

Specifies the name used to register a durable subscription.

messageSelector

Specifies the string value of a message selector to use. For more information on the syntax used to specify message selectors, see the JMS 1.1 specification.

transactional

Specifies whether the local JMS broker will create transactions around message processing. The default is false. [a]

[a] Currently, setting the transactional attribute to true is not supported by the runtime.
Example

Example 14.8, “WSDL for a JMS provider endpoint” shows the WSDL for configuring a JMS provider endpoint.

Example 14.8. WSDL for a JMS provider endpoint

<service name="JMSService">
  <port binding="tns:Greeter_SOAPBinding" name="SoapPort">
    <jms:address jndiConnectionFactoryName="ConnectionFactory"
                 jndiDestinationName="dynamicQueues/test.Celtix.jmstransport" >
      <jms:JMSNamingProperty name="java.naming.factory.initial"
                             value="org.activemq.jndi.ActiveMQInitialContextFactory" />
      <jms:JMSNamingProperty name="java.naming.provider.url"
                             value="tcp://localhost:61616" />
    </jms:address>
    <jms:server messageSelector="cxf_message_selector"
                useMessageIDAsCorrelationID="true"
                transactional="true"
                durableSubscriberName="cxf_subscriber" />
  </port>
</service>

14.6. Using a Named Reply Destination

Overview

By default, Apache CXF endpoints using JMS create a temporary queue for sending replies back and forth. If you prefer to use named queues, you can configure the queue used to send replies as part of an endpoint’s JMS configuration.

Setting the reply destination name

You specify the reply destination using either the jmsReplyDestinationName attribute or the jndiReplyDestinationName attribute in the endpoint’s JMS configuration. A client endpoint will listen for replies on the specified destination and it will specify the value of the attribute in the ReplyTo field of all outgoing requests. A service endpoint will use the value of the jndiReplyDestinationName attribute as the location for placing replies if there is no destination specified in the request’s ReplyTo field.

Example

Example 14.9, “JMS Consumer Specification Using a Named Reply Queue” shows the configuration for a JMS client endpoint.

Example 14.9. JMS Consumer Specification Using a Named Reply Queue

<jms:conduit name="{http://cxf.apache.org/jms_endpt}HelloWorldJMSPort.jms-conduit">
    <jms:address destinationStyle="queue"
                 jndiConnectionFactoryName="myConnectionFactory"
                 jndiDestinationName="myDestination"
                 jndiReplyDestinationName="myReplyDestination" >
      <jms:JMSNamingProperty name="java.naming.factory.initial"
                             value="org.apache.cxf.transport.jms.MyInitialContextFactory" />
      <jms:JMSNamingProperty name="java.naming.provider.url"
                             value="tcp://localhost:61616" />
    </jms:address>
  </jms:conduit>

Chapter 15. Integrating with Apache ActiveMQ

Overview

If you are using Apache ActiveMQ as your JMS provider, the JNDI name of your destinations can be specified in a special format that dynamically creates JNDI bindings for queues or topics. This means that it is not necessary to configure the JMS provider in advance with the JNDI bindings for your queues or topics.

The initial context factory

The key to integrating Apache ActiveMQ with JNDI is the ActiveMQInitialContextFactory class. This class is used to create a JNDI InitialContext instance, which you can then use to access JMS destinations in the JMS broker.

Example 15.1, “SOAP/JMS WSDL to connect to Apache ActiveMQ” shows SOAP/JMS WSDL extensions to create a JNDI InitialContext that is integrated with Apache ActiveMQ.

Example 15.1. SOAP/JMS WSDL to connect to Apache ActiveMQ

<soapjms:jndiInitialContextFactory>
  org.apache.activemq.jndi.ActiveMQInitialContextFactory
</soapjms:jndiInitialContextFactory>
<soapjms:jndiURL>tcp://localhost:61616</soapjms:jndiURL>

In Example 15.1, “SOAP/JMS WSDL to connect to Apache ActiveMQ”, the Apache ActiveMQ client connects to the broker port located at tcp://localhost:61616.

Looking up the connection factory

As well as creating a JNDI InitialContext instance, you must specify the JNDI name that is bound to a javax.jms.ConnectionFactory instance. In the case of Apache ActiveMQ, there is a predefined binding in the InitialContext instance, which maps the JNDI name ConnectionFactory to an ActiveMQConnectionFactory instance. Example 15.2, “SOAP/JMS WSDL for specifying the Apache ActiveMQ connection factory” shaows the SOAP/JMS extension element for specifying the Apache ActiveMQ connection factory.

Example 15.2. SOAP/JMS WSDL for specifying the Apache ActiveMQ connection factory

<soapjms:jndiConnectionFactoryName>
  ConnectionFactory
</soapjms:jndiConnectionFactoryName>

Syntax for dynamic destinations

To access queues or topics dynamically, specify the destination’s JNDI name as a JNDI composite name in either of the following formats:

dynamicQueues/QueueName
dynamicTopics/TopicName

QueueName and TopicName are the names that the Apache ActiveMQ broker uses. They are not abstract JNDI names.

Example 15.3, “WSDL port specification with a dynamically created queue” shows a WSDL port that uses a dynamically created queue.

Example 15.3. WSDL port specification with a dynamically created queue

<service name="JMSService">
  <port binding="tns:GreeterBinding" name="JMSPort">
    <jms:address jndiConnectionFactoryName="ConnectionFactory"
                 jndiDestinationName="dynamicQueues/greeter.request.queue" >
      <jms:JMSNamingProperty name="java.naming.factory.initial"
                             value="org.activemq.jndi.ActiveMQInitialContextFactory" />
      <jms:JMSNamingProperty name="java.naming.provider.url"
                             value="tcp://localhost:61616" />
    </jms:address>
  </port>
</service>

When the application attempts to open the JMS connection, Apache ActiveMQ will check to see if a queue with the JNDI name greeter.request.queue exists. If it does not exist, it will create a new queue and bind it to the JNDI name greeter.request.queue.

Chapter 16. Conduits

Abstract

Conduits are a low-level piece of the transport architecture that are used to implement outbound connections. Their behavior and life-cycle can effect system performance and processing load.

Overview

Conduits manage the client-side, or outbound, transport details in the Apache CXF runtime. They are responsible for opening ports, establishing outbound connections, sending messages, and listening for any responses between an application and a single external endpoint. If an application connects to multiple endpoints, it will have one conduit instance for each endpoint.

Each transport type implements its own conduit using the Conduit interface. This allows for a standardized interface between the application level functionality and the transports.

In general, you only need to worry about the conduits being used by your application when configuring the client-side transport details. The underlying semantics of how the runtime handles conduits is, generally, not something a developer needs to worry about.

However, there are cases when an understanding of conduit’s can prove helpful:

  • Implementing a custom transport
  • Advanced application tuning to manage limited resources

Conduit life-cycle

Conduits are managed by the client implementation object. Once created, a conduit lives for the duration of the client implementation object. The conduit’s life-cycle is:

  1. When the client implementation object is created, it is given a reference to a ConduitSelector object.
  2. When the client needs to send a message is request’s a reference to a conduit from the conduit selector.

    If the message is for a new endpoint, the conduit selector creates a new conduit and passes it to the client implementation. Otherwise, it passes the client a reference to the conduit for the target endpoint.

  3. The conduit sends messages when needed.
  4. When the client implementation object is destroyed, all of the conduits associated with it are destroyed.

Conduit weight

The weight of a conduit object depends on the transport implementation. HTTP conduits are extremely light weight. JMS conduits are heavy because they are associated with the JMS Session object and one or more JMSListenerContainer objects.

Part IV. Configuring Web Service Endpoints

This guide describes how to create Apache CXF endpoints in Red Hat Fuse.

Chapter 17. Configuring JAX-WS Endpoints

Abstract

JAX-WS endpoints are configured using one of three Spring configuration elements. The correct element depends on what type of endpoint you are configuring and which features you wish to use. For consumers you use the jaxws:client element. For service providers you can use either the jaxws:endpoint element or the jaxws:server element.

The information used to define an endpoint is typically defined in the endpoint’s contract. You can use the configuration element’s to override the information in the contract. You can also use the configuration elements to provide information that is not provided in the contract.

You must use the configuration elements to activate advanced features such as WS-RM. This is done by providing child elements to the endpoint’s configuration element. Note that when dealing with endpoints developed using a Java-first approach it is likely that the SEI serving as the endpoint’s contract is lacking information about the type of binding and transport to use.

17.1. Configuring Service Providers

17.1.1. Elements for Configuring Service Providers

Apache CXF has two elements that can be used to configure a service provider:

The differences between the two elements are largely internal to the runtime. The jaxws:endpoint element injects properties into the org.apache.cxf.jaxws.EndpointImpl object created to support a service endpoint. The jaxws:server element injects properties into the org.apache.cxf.jaxws.support.JaxWsServerFactoryBean object created to support the endpoint. The EndpointImpl object passes the configuration data to the JaxWsServerFactoryBean object. The JaxWsServerFactoryBean object is used to create the actual service object. Because either configuration element will configure a service endpoint, you can choose based on the syntax you prefer.

17.1.2. Using the jaxws:endpoint Element

Overview

The jaxws:endpoint element is the default element for configuring JAX-WS service providers. Its attributes and children specify all of the information needed to instantiate a service provider. Many of the attributes map to information in the service’s contract. The children are used to configure interceptors and other advanced features.

Identifying the endpoint being configured

For the runtime to apply the configuration to the proper service provider, it must be able to identify it. The basic means for identifying a service provider is to specify the class that implements the endpoint. This is done using the jaxws:endpoint element’s implementor attribute.

For instances where different endpoint’s share a common implementation, it is possible to provide different configuration for each endpoint. There are two approaches for distinguishing a specific endpoint in configuration:

  • a combination of the serviceName attribute and the endpointName attribute

    The serviceName attribute specifies the wsdl:service element defining the service’s endpoint. The endpointName attribute specifies the specific wsdl:port element defining the service’s endpoint. Both attributes are specified as QNames using the format ns:name. ns is the namespace of the element and name is the value of the element’s name attribute.

    Note

    If the wsdl:service element only has one wsdl:port element, the endpointName attribute can be omitted.

  • the name attribute

    The name attribute specifies the QName of the specific wsdl:port element defining the service’s endpoint. The QName is provided in the format {ns}localPart. ns is the namespace of the wsdl:port element and localPart is the value of the wsdl:port element’s name attribute.

Attributes

The attributes of the jaxws:endpoint element configure the basic properties of the endpoint. These properties include the address of the endpoint, the class that implements the endpoint, and the bus that hosts the endpoint.

Table 17.1, “Attributes for Configuring a JAX-WS Service Provider Using the jaxws:endpoint Element” describes the attribute of the jaxws:endpoint element.

Table 17.1. Attributes for Configuring a JAX-WS Service Provider Using the jaxws:endpoint Element
AttributeDescription

id

Specifies a unique identifier that other configuration elements can use to refer to the endpoint.

implementor

Specifies the class implementing the service. You can specify the implementation class using either the class name or an ID reference to a Spring bean configuring the implementation class. This class must be on the classpath.

implementorClass

Specifies the class implementing the service. This attribute is useful when the value provided to the implementor attribute is a reference to a bean that is wrapped using Spring AOP.

address

Specifies the address of an HTTP endpoint. This value overrides the value specified in the services contract.

wsdlLocation

Specifies the location of the endpoint’s WSDL contract. The WSDL contract’s location is relative to the folder from which the service is deployed.

endpointName

Specifies the value of the service’s wsdl:port element’s name attribute. It is specified as a QName using the format ns:name where ns is the namespace of the wsdl:port element.

serviceName

Specifies the value of the service’s wsdl:service element’s name attribute. It is specified as a QName using the format ns:name where ns is the namespace of the wsdl:service element.

publish

Specifies if the service should be automatically published. If this is set to false, the developer must explicitly publish the endpointas described in Chapter 31, Publishing a Service.

bus

Specifies the ID of the Spring bean configuring the bus used to manage the service endpoint. This is useful when configuring several endpoints to use a common set of features.

bindingUri

Specifies the ID of the message binding the service uses. A list of valid binding IDs is provided in Chapter 23, Apache CXF Binding IDs.

name

Specifies the stringified QName of the service’s wsdl:port element. It is specified as a QName using the format {ns}localPart. ns is the namespace of the wsdl:port element and localPart is the value of the wsdl:port element’s name attribute.

abstract

Specifies if the bean is an abstract bean. Abstract beans act as parents for concrete bean definitions and are not instantiated. The default is false. Setting this to true instructs the bean factory not to instantiate the bean.

depends-on

Specifies a list of beans that the endpoint depends on being instantiated before it can be instantiated.

createdFromAPI

Specifies that the user created that bean using Apache CXF APIs, such as Endpoint.publish() or Service.getPort().

The default is false.

Setting this to true does the following:

  • Changes the internal name of the bean by appending .jaxws-endpoint to its id
  • Makes the bean abstract

publishedEndpointUrl

The URL that is placed in the address element of the generated WSDL. If this value is not specified, the value of the address attribute is used. This attribute is useful when the "public" URL is not be the same as the URL on which the service is deployed.

In addition to the attributes listed in Table 17.1, “Attributes for Configuring a JAX-WS Service Provider Using the jaxws:endpoint Element”, you might need to use multiple xmlns:shortName attributes to declare the namespaces used by the endpointName and serviceName attributes.

Example

Example 17.1, “Simple JAX-WS Endpoint Configuration” shows the configuration for a JAX-WS endpoint that specifies the address where the endpoint is published. The example assumes that you want to use the defaults for all other values or that the implementation has specified values in the annotations.

Example 17.1. Simple JAX-WS Endpoint Configuration

<beans ...
  xmlns:jaxws="http://cxf.apache.org/jaxws"
  ...
  schemaLocation="...
    http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd
    ...">
  <jaxws:endpoint id="example"
                  implementor="org.apache.cxf.example.DemoImpl"
                  address="http://localhost:8080/demo" />
</beans>

Example 17.2, “JAX-WS Endpoint Configuration with a Service Name” shows the configuration for a JAX-WS endpoint whose contract contains two service definitions. In this case, you must specify which service definition to instantiate using the serviceName attribute.

Example 17.2. JAX-WS Endpoint Configuration with a Service Name

<beans ...
  xmlns:jaxws="http://cxf.apache.org/jaxws"
  ...
  schemaLocation="...
    http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd
    ...">

  <jaxws:endpoint id="example2"
                  implementor="org.apache.cxf.example.DemoImpl"
                  serviceName="samp:demoService2"
                  xmlns:samp="http://org.apache.cxf/wsdl/example" />

</beans>

The xmlns:samp attribute specifies the namespace in which the WSDL service element is defined.

Example 17.3, “JAX-WS Endpoint Configuration with with HTTP/2 enabled” shows the configuration for a JAX-WS endpoint that specifies the address with HTTP/2 enabled.

Configuring HTTP/2 for Apache CXF

HTTP/2 is supported when using the standalone Apache CXF Undertow transport (http-undertow) on Apache Karaf. To enable the HTTP/2 protocol you must set the jaxws:endpoint element’s address attribute as an absolute URL and set the org.apache.cxf.transports.http_undertow.EnableHttp2 property as true.

Note

This HTTP/2 implementation only supports server side HTTP/2 transport with plain HTTP or HTTPS.

Example 17.3. JAX-WS Endpoint Configuration with with HTTP/2 enabled

<beans ...
  xmlns:jaxws="http://cxf.apache.org/jaxws"
  ...
  schemaLocation="...
  http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd
  ...">

  <cxf:bus>
    <cxf:properties>
        <entry key="org.apache.cxf.transports.http_undertow.EnableHttp2" value="true"/>
    </cxf:properties>
  </cxf:bus>

  <jaxws:endpoint id="example3"
                implementor="org.apache.cxf.example.DemoImpl"
                address="http://localhost:8080/demo" />
  </jaxws:endpoint>

</beans>
Note

For improved performance, Red Hat recommends using the servlet transport on Apache Karaf (pax-web-undertow) which enables centralized configuration and tuning of the web container, however, pax-web-undertow does not support the HTTP/2 transport protocol.

17.1.3. Using the jaxws:server Element

Overview

The jaxws:server element is an element for configuring JAX-WS service providers. It injects the configuration information into the org.apache.cxf.jaxws.support.JaxWsServerFactoryBean. This is a Apache CXF specific object. If you are using a pure Spring approach to building your services, you will not be forced to use Apache CXF specific APIs to interact with the service.

The attributes and children of the jaxws:server element specify all of the information needed to instantiate a service provider. The attributes specify the information that is required to instantiate an endpoint. The children are used to configure interceptors and other advanced features.

Identifying the endpoint being configured

In order for the runtime to apply the configuration to the proper service provider, it must be able to identify it. The basic means for identifying a service provider is to specify the class that implements the endpoint. This is done using the jaxws:server element’s serviceBean attribute.

For instances where different endpoint’s share a common implementation, it is possible to provide different configuration for each endpoint. There are two approaches for distinguishing a specific endpoint in configuration:

  • a combination of the serviceName attribute and the endpointName attribute

    The serviceName attribute specifies the wsdl:service element defining the service’s endpoint. The endpointName attribute specifies the specific wsdl:port element defining the service’s endpoint. Both attributes are specified as QNames using the format ns:name. ns is the namespace of the element and name is the value of the element’s name attribute.

    Note

    If the wsdl:service element only has one wsdl:port element, the endpointName attribute can be omitted.

  • the name attribute

    The name attribute specifies the QName of the specific wsdl:port element defining the service’s endpoint. The QName is provided in the format {ns}localPart. ns is the namespace of the wsdl:port element and localPart is the value of the wsdl:port element’s name attribute.

Attributes

The attributes of the jaxws:server element configure the basic properties of the endpoint. These properties include the address of the endpoint, the class that implements the endpoint, and the bus that hosts the endpoint.

Table 17.2, “Attributes for Configuring a JAX-WS Service Provider Using the jaxws:server Element” describes the attribute of the jaxws:server element.

Table 17.2. Attributes for Configuring a JAX-WS Service Provider Using the jaxws:server Element
AttributeDescription

id

Specifies a unique identifier that other configuration elements can use to refer to the endpoint.

serviceBean

Specifies the class implementing the service. You can specify the implementation class using either the class name or an ID reference to a Spring bean configuring the implementation class. This class must be on the classpath.

serviceClass

Specifies the class implementing the service. This attribute is useful when the value provided to the implementor attribute is a reference to a bean that is wrapped using Spring AOP.

address

Specifies the address of an HTTP endpoint. This value will override the value specified in the services contract.

wsdlLocation

Specifies the location of the endpoint’s WSDL contract. The WSDL contract’s location is relative to the folder from which the service is deployed.

endpointName

Specifies the value of the service’s wsdl:port element’s name attribute. It is specified as a QName using the format ns:name, where ns is the namespace of the wsdl:port element.

serviceName

Specifies the value of the service’s wsdl:service element’s name attribute. It is specified as a QName using the format ns:name, where ns is the namespace of the wsdl:service element.

publish

Specifies if the service should be automatically published. If this is set to false, the developer must explicitly publish the endpointas described in Chapter 31, Publishing a Service.

bus

Specifies the ID of the Spring bean configuring the bus used to manage the service endpoint. This is useful when configuring several endpoints to use a common set of features.

bindingId

Specifies the ID of the message binding the service uses. A list of valid binding IDs is provided in Chapter 23, Apache CXF Binding IDs.

name

Specifies the stringified QName of the service’s wsdl:port element. It is specified as a QName using the format {ns}localPart, where ns is the namespace of the wsdl:port element and localPart is the value of the wsdl:port element’s name attribute.

abstract

Specifies if the bean is an abstract bean. Abstract beans act as parents for concrete bean definitions and are not instantiated. The default is false. Setting this to true instructs the bean factory not to instantiate the bean.

depends-on

Specifies a list of beans that the endpoint depends on being instantiated before the endpoint can be instantiated.

createdFromAPI

Specifies that the user created that bean using Apache CXF APIs, such as Endpoint.publish() or Service.getPort().

The default is false.

Setting this to true does the following:

  • Changes the internal name of the bean by appending .jaxws-endpoint to its id
  • Makes the bean abstract

In addition to the attributes listed in Table 17.2, “Attributes for Configuring a JAX-WS Service Provider Using the jaxws:server Element”, you might need to use multiple xmlns:shortName attributes to declare the namespaces used by the endpointName and serviceName attributes.

Example

Example 17.4, “Simple JAX-WS Server Configuration” shows the configuration for a JAX-WS endpoint that specifies the address where the endpoint is published.

Example 17.4. Simple JAX-WS Server Configuration

<beans ...
  xmlns:jaxws="http://cxf.apache.org/jaxws"
  ...
  schemaLocation="...
    http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd
    ...">
  <jaxws:server id="exampleServer"
                  serviceBean="org.apache.cxf.example.DemoImpl"
                  address="http://localhost:8080/demo" />
</beans>

17.1.4. Adding Functionality to Service Providers

Overview

The jaxws:endpoint and the jaxws:server elements provide the basic configuration information needed to instantiate a service provider. To add functionality to your service provider or to perform advanced configuration you must add child elements to the configuration.

Child elements allow you to do the following:

Elements

Table 17.3, “Elements Used to Configure JAX-WS Service Providers” describes the child elements that jaxws:endpoint supports.

Table 17.3. Elements Used to Configure JAX-WS Service Providers
ElementDescription

jaxws:handlers

Specifies a list of JAX-WS Handler implementations for processing messages. For more information on JAX-WS Handler implementations see Chapter 43, Writing Handlers.

jaxws:inInterceptors

Specifies a list of interceptors that process inbound requests. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxws:inFaultInterceptors

Specifies a list of interceptors that process inbound fault messages. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxws:outInterceptors

Specifies a list of interceptors that process outbound replies. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxws:outFaultInterceptors

Specifies a list of interceptors that process outbound fault messages. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxws:binding

Specifies a bean configuring the message binding used by the endpoint. Message bindings are configured using implementations of the org.apache.cxf.binding.BindingFactory interface.[a]

jaxws:dataBinding [b]

Specifies the class implementing the data binding used by the endpoint. This is specified using an embedded bean definition.

jaxws:executor

Specifies a Java executor that is used for the service. This is specified using an embedded bean definition.

jaxws:features

Specifies a list of beans that configure advanced features of Apache CXF. You can provide either a list of bean references or a list of embedded beans.

jaxws:invoker

Specifies an implementation of the org.apache.cxf.service.Invoker interface used by the service. [c]

jaxws:properties

Specifies a Spring map of properties that are passed along to the endpoint. These properties can be used to control features like enabling MTOM support.

jaxws:serviceFactory

Specifies a bean configuring the JaxWsServiceFactoryBean object used to instantiate the service.

[a] The SOAP binding is configured using the soap:soapBinding bean.
[b] The jaxws:endpoint element does not support the jaxws:dataBinding element.
[c] The Invoker implementation controls how a service is invoked. For example, it controls whether each request is handled by a new instance of the service implementation or if state is preserved across invocations.

17.1.5. Enable Schema Validation on a JAX-WS Endpoint

Overview

You can set the schema-validation-enabled property to enable schema validation on a jaxws:endpoint element or on a jaxws:server element. When schema validation is enabled, the messages sent between client and server are checked for conformity to the schema. By default, schema validation is turned off, because it has a significant impact on performance.

Example

To enable schema validation on a JAX-WS endpoint, set the schema-validation-enabled property in the jaxws:properties child element of the jaxws:endpoint element or of the jaxws:server element. For example, to enable schema validation on a jaxws:endpoint element:

<jaxws:endpoint name="{http://apache.org/hello_world_soap_http}SoapPort"
    wsdlLocation="wsdl/hello_world.wsdl"
    createdFromAPI="true">
    <jaxws:properties>
        <entry key="schema-validation-enabled" value="BOTH" />
    </jaxws:properties>
</jaxws:endpoint>

For the list of allowed values of the schema-validation-enabled property, see Section 24.3.4.7, “Schema Validation Type Values”.

17.2. Configuring Consumer Endpoints

Overview

JAX-WS consumer endpoints are configured using the jaxws:client element. The element’s attributes provide the basic information necessary to create a consumer.

To add other functionality, like WS-RM, to the consumer you add children to the jaxws:client element. Child elements are also used to configure the endpoint’s logging behavior and to inject other properties into the endpoint’s implementation.

Basic Configuration Properties

The attributes described in Table 17.4, “Attributes Used to Configure a JAX-WS Consumer” provide the basic information necessary to configure a JAX-WS consumer. You only need to provide values for the specific properties you want to configure. Most of the properties have sensible defaults, or they rely on information provided by the endpoint’s contract.

Table 17.4. Attributes Used to Configure a JAX-WS Consumer
AttributeDescription

address

Specifies the HTTP address of the endpoint where the consumer will make requests. This value overrides the value set in the contract.

bindingId

Specifies the ID of the message binding the consumer uses. A list of valid binding IDs is provided in Chapter 23, Apache CXF Binding IDs.

bus

Specifies the ID of the Spring bean configuring the bus managing the endpoint.

endpointName

Specifies the value of the wsdl:port element’s name attribute for the service on which the consumer is making requests. It is specified as a QName using the format ns:name, where ns is the namespace of the wsdl:port element.

serviceName

Specifies the value of the wsdl:service element’s name attribute for the service on which the consumer is making requests. It is specified as a QName using the format ns:name where ns is the namespace of the wsdl:service element.

username

Specifies the username used for simple username/password authentication.

password

Specifies the password used for simple username/password authentication.

serviceClass

Specifies the name of the service endpoint interface(SEI).

wsdlLocation

Specifies the location of the endpoint’s WSDL contract. The WSDL contract’s location is relative to the folder from which the client is deployed.

name

Specifies the stringified QName of the wsdl:port element for the service on which the consumer is making requests. It is specified as a QName using the format {ns}localPart, where ns is the namespace of the wsdl:port element and localPart is the value of the wsdl:port element’s name attribute.

abstract

Specifies if the bean is an abstract bean. Abstract beans act as parents for concrete bean definitions and are not instantiated. The default is false. Setting this to true instructs the bean factory not to instantiate the bean.

depends-on

Specifies a list of beans that the endpoint depends on being instantiated before it can be instantiated.

createdFromAPI

Specifies that the user created that bean using Apache CXF APIs like Service.getPort().

The default is false.

Setting this to true does the following:

  • Changes the internal name of the bean by appending .jaxws-client to its id
  • Makes the bean abstract

In addition to the attributes listed in Table 17.4, “Attributes Used to Configure a JAX-WS Consumer”, it might be necessary to use multiple xmlns:shortName attributes to declare the namespaces used by the endpointName and the serviceName attributes.

Adding functionality

To add functionality to your consumer or to perform advanced configuration, you must add child elements to the configuration.

Child elements allow you to do the following:

Table 17.5, “Elements For Configuring a Consumer Endpoint” describes the child element’s you can use to configure a JAX-WS consumer.

Table 17.5. Elements For Configuring a Consumer Endpoint
ElementDescription

jaxws:binding

Specifies a bean configuring the message binding used by the endpoint. Message bindings are configured using implementations of the org.apache.cxf.binding.BindingFactory interface.[a]

jaxws:dataBinding

Specifies the class implementing the data binding used by the endpoint. You specify this using an embedded bean definition. The class implementing the JAXB data binding is org.apache.cxf.jaxb.JAXBDataBinding.

jaxws:features

Specifies a list of beans that configure advanced features of Apache CXF. You can provide either a list of bean references or a list of embedded beans.

jaxws:handlers

Specifies a list of JAX-WS Handler implementations for processing messages. For more information in JAX-WS Handler implementations see Chapter 43, Writing Handlers.

jaxws:inInterceptors

Specifies a list of interceptors that process inbound responses. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxws:inFaultInterceptors

Specifies a list of interceptors that process inbound fault messages. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxws:outInterceptors

Specifies a list of interceptors that process outbound requests. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxws:outFaultInterceptors

Specifies a list of interceptors that process outbound fault messages. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxws:properties

Specifies a map of properties that are passed to the endpoint.

jaxws:conduitSelector

Specifies an org.apache.cxf.endpoint.ConduitSelector implementation for the client to use. A ConduitSelector implementation will override the default process used to select the Conduit object that is used to process outbound requests.

[a] The SOAP binding is configured using the soap:soapBinding bean.

Example

Example 17.5, “Simple Consumer Configuration” shows a simple consumer configuration.

Example 17.5. Simple Consumer Configuration

<beans ...
  xmlns:jaxws="http://cxf.apache.org/jaxws"
  ...
  schemaLocation="...
    http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd
    ...">
  <jaxws:client id="bookClient"
                serviceClass="org.apache.cxf.demo.BookClientImpl"
                address="http://localhost:8080/books"/>
  ...
</beans>

Enable schema validation on a JAX-WS consumer

To enable schema validation on a JAX-WS consumer, set the schema-validation-enabled property in the jaxws:properties child element of the jaxws:client element—for example:

<jaxws:client name="{http://apache.org/hello_world_soap_http}SoapPort"
    createdFromAPI="true">
    <jaxws:properties>
        <entry key="schema-validation-enabled" value="BOTH" />
    </jaxws:properties>
</jaxws:client>

For the list of allowed values of the schema-validation-enabled property, see Section 24.3.4.7, “Schema Validation Type Values”.

Chapter 18. Configuring JAX-RS Endpoints

Abstract

This chapter explains how to instantiate and configure JAX-RS server endpoints in Blueprint XML and in Spring XML, and also how to instantiate and configure JAX-RS client endpoints (client proxy beans) in XML

18.1. Configuring JAX-RS Server Endpoints

18.1.1. Defining a JAX-RS Server Endpoint

Basic server endpoint definition

To define a JAX-RS server endpoint in XML, you need to specify at least the following:

  1. A jaxrs:server element, which is used to define the endpoint in XML. Note that the jaxrs: namespace prefix maps to different namespaces in Blueprint and in Spring respectively.
  2. The base URL of the JAX-RS service, using the address attribute of the jaxrs:server element. Note that there are two different ways of specifying the address URL, which affects how the endpoint gets deployed:

    • As a relative URL—for example, /customers. In this case, the endpoint is deployed into the default HTTP container, and the endpoint’s base URL is implicitly obtained by combining the CXF servlet base URL with the specified relative URL.

      For example, if you deploy a JAX-RS endpoint to the Fuse container, the specified /customers URL would get resolved to the URL, http://Hostname:8181/cxf/customers (assuming that the container is using the default 8181 port).

    • As an absolute URL — for example, http://0.0.0.0:8200/cxf/customers. In this case, a new HTTP listener port is opened for the JAX-RS endpoint (if it is not already open). For example, in the context of Fuse, a new Undertow container would implicitly be created to host the JAX-RS endpoint. The special IP address, 0.0.0.0, acts as a wildcard, matching any of the hostnames assigned to the current host (which can be useful on multi-homed host machines).
  3. One or more JAX-RS root resource classes, which provide the implementation of the JAX-RS service. The simplest way to specify the resource classes is to list them inside a jaxrs:serviceBeans element.
Blueprint example

The following Blueprint XML example shows how to define a JAX-RS endpoint, which specifies the relative address, /customers (so that it deploys into the default HTTP container) and is implemented by the service.CustomerService resource class:

<blueprint xmlns="http://www.osgi.org/xmlns/blueprint/v1.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:jaxrs="http://cxf.apache.org/blueprint/jaxrs"
    xmlns:cxf="http://cxf.apache.org/blueprint/core"
    xsi:schemaLocation="
http://www.osgi.org/xmlns/blueprint/v1.0.0 https://www.osgi.org/xmlns/blueprint/v1.0.0/blueprint.xsd
http://cxf.apache.org/blueprint/jaxrs http://cxf.apache.org/schemas/blueprint/jaxrs.xsd
http://cxf.apache.org/blueprint/core http://cxf.apache.org/schemas/blueprint/core.xsd
">

    <cxf:bus>
        <cxf:features>
            <cxf:logging/>
        </cxf:features>
    </cxf:bus>

     <jaxrs:server id="customerService" address="/customers">
        <jaxrs:serviceBeans>
           <ref component-id="serviceBean" />
        </jaxrs:serviceBeans>
     </jaxrs:server>

     <bean id="serviceBean" class="service.CustomerService"/>
</blueprint>
Blueprint XML namespaces

To define a JAX-RS endpoint in Blueprint, you typically require at least the following XML namespaces:

PrefixNamespace

(default)

http://www.osgi.org/xmlns/blueprint/v1.0.0

cxf

http://cxf.apache.org/blueprint/core

jaxrs

http://cxf.apache.org/blueprint/jaxrs

Spring example

The following Spring XML example shows how to define a JAX-RS endpoint, which specifies the relative address, /customers (so that it deploys into the default HTTP container) and is implemented by the service.CustomerService resource class:

<beans xmlns="http://www.springframework.org/schema/beans"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xmlns:jaxrs="http://cxf.apache.org/jaxrs"
      xsi:schemaLocation="
         http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
         http://cxf.apache.org/jaxrs http://cxf.apache.org/schemas/jaxrs.xsd">

     <jaxrs:server id="customerService" address="/customers">
        <jaxrs:serviceBeans>
           <ref bean="serviceBean"/>
        </jaxrs:serviceBeans>
     </jaxrs:server>

     <bean id="serviceBean" class="service.CustomerService"/>
</beans>
Spring XML namespaces

To define a JAX-RS endpoint in Spring, you typically require at least the following XML namespaces:

PrefixNamespace

(default)

http://www.springframework.org/schema/beans

cxf

http://cxf.apache.org/core

jaxrs

http://cxf.apache.org/jaxrs

Auto-discovery in Spring XML

(Spring only) Instead of specifying the JAX-RS root resource classes explicitly, Spring XML enables you to configure auto-discovery, so that specific Java packages are searched for resource classes (classes annotated by @Path) and all of the discovered resource classes are automatically attached to the endpoint. In this case, you need to specify just the address attribute and the basePackages attribute in the jaxrs:server element.

For example, to define a JAX-RS endpoint which uses all of the JAX-RS resource classes under the a.b.c Java package, you can define the endpoint in Spring XML, as follows:

<jaxrs:server address="/customers" basePackages="a.b.c"/>

The auto-discovery mechanism also discovers and installs into the endpoint any JAX-RS provider classes that it finds under the specified Java packages.

Lifecycle management in Spring XML

(Spring only) Spring XML enables you to control the lifecycle of beans by setting the scope attribute on a bean element. The following scope values are supported by Spring:

singleton
(Default) Creates a single bean instance, which is used everywhere and lasts for the entire lifetime of the Spring container.
prototype
Creates a new bean instance every time the bean is injected into another bean or when a bean is obtained by invoking getBean() on the bean registry.
request
(Only available in a Web-aware container) Creates a new bean instance for every request invoked on the bean.
session
(Only available in a Web-aware container) Creates a new bean for the lifetime of a single HTTP session.
globalSession
(Only available in a Web-aware container) Creates a new bean for the lifetime of a single HTTP session that is shared between portlets.

For more details about Spring scopes, please consult the Spring framework documentation on Bean scopes.

Note that Spring scopes do not work properly, if you specify JAX-RS resource beans through the jaxrs:serviceBeans element. If you specify the scope attribute on the resource beans in this case, the scope attribute is effectively ignored.

In order to make bean scopes work properly within a JAX-RS server endpoint, you require a level of indirection that is provided by a service factory. The simplest way to configure bean scopes is to specify resource beans using the beanNames attribute on the jaxrs:server element, as follows:

<beans ... >
  <jaxrs:server id="customerService" address="/service1"
    beanNames="customerBean1 customerBean2"/>

  <bean id="customerBean1" class="demo.jaxrs.server.CustomerRootResource1" scope="prototype"/>
  <bean id="customerBean2" class="demo.jaxrs.server.CustomerRootResource2"  scope="prototype"/>
</beans>

Where the preceding example configures two resource beans, customerBean1 and customerBean2. The beanNames attribute is specified as a space-separated list of resource bean IDs.

For the ultimate degree of flexibility, you have the option of defining service factory objects explicitly, when you configure the JAX-RS server endpoint, using the jaxrs:serviceFactories element. This more verbose approach has the advantage that you can replace the default service factory implementation with your custom implementation, thus giving you ultimate control over the bean lifecycle. The following example shows how to configure the two resource beans, customerBean1 and customerBean2, using this approach:

<beans ... >
  <jaxrs:server id="customerService" address="/service1">
    <jaxrs:serviceFactories>
      <ref bean="sfactory1" />
      <ref bean="sfactory2" />
    </jaxrs:serviceFactories>
  </jaxrs:server>

  <bean id="sfactory1" class="org.apache.cxf.jaxrs.spring.SpringResourceFactory">
     <property name="beanId" value="customerBean1"/>
  </bean>
  <bean id="sfactory2" class="org.apache.cxf.jaxrs.spring.SpringResourceFactory">
     <property name="beanId" value="customerBean2"/>
  </bean>

  <bean id="customerBean1" class="demo.jaxrs.server.CustomerRootResource1" scope="prototype"/>
  <bean id="customerBean2" class="demo.jaxrs.server.CustomerRootResource2"  scope="prototype"/>
</beans>
Note

If you specify a non-singleton lifecycle, it is often a good idea to implement and register a org.apache.cxf.service.Invoker bean (where the instance can be registered by referencing it from a jaxrs:server/jaxrs:invoker element).

Attaching a WADL document

You can optionally associate a WADL document with the JAX-RS server endpoint using the docLocation attribute on the jaxrs:server element. For example:

<jaxrs:server address="/rest" docLocation="wadl/bookStore.wadl">
   <jaxrs:serviceBeans>
      <bean class="org.bar.generated.BookStore"/>
   </jaxrs:serviceBeans>
</jaxrs:server>
Schema validation

If you have some external XML schemas, for describing message content in JAX-B format, you can associate these external schemas with the JAX-RS server endpoint through the jaxrs:schemaLocations element.

For example, if you have associated the server endpoint with a WADL document and you also want to enable schema validation on incoming messages, you can specify associated XML schema files as follows:

<jaxrs:server address="/rest"
              docLocation="wadl/bookStore.wadl">
   <jaxrs:serviceBeans>
     <bean class="org.bar.generated.BookStore"/>
   </jaxrs:serviceBeans>
   <jaxrs:schemaLocations>
     <jaxrs:schemaLocation>classpath:/schemas/a.xsd</jaxrs:schemaLocation>
     <jaxrs:schemaLocation>classpath:/schemas/b.xsd</jaxrs:schemaLocation>
   </jaxrs:schemaLocations>
</jaxrs:server>

Alternatively, if you want to include all of the schema files, *.xsd, in a given directory, you can just specify the directory name, as follows:

<jaxrs:server address="/rest"
              docLocation="wadl/bookStore.wadl">
   <jaxrs:serviceBeans>
     <bean class="org.bar.generated.BookStore"/>
   </jaxrs:serviceBeans>
   <jaxrs:schemaLocations>
     <jaxrs:schemaLocation>classpath:/schemas/</jaxrs:schemaLocation>
   </jaxrs:schemaLocations>
</jaxrs:server>

Specifying schemas in this way is generally useful for any kind of functionality that requires access to the JAX-B schemas.

Specifying the data binding

You can use the jaxrs:dataBinding element to specify the data binding that encodes the message body in request and reply messages. For example, to specify the JAX-B data binding, you could configure a JAX-RS endpoint as follows:

<jaxrs:server id="jaxbbook" address="/jaxb">
  <jaxrs:serviceBeans>
    <ref bean="serviceBean" />
  </jaxrs:serviceBeans>
  <jaxrs:dataBinding>
    <bean class="org.apache.cxf.jaxb.JAXBDataBinding"/>
  </jaxrs:dataBinding>
</jaxrs:server>>

Or to specify the Aegis data binding, you could configure a JAX-RS endpoint as follows:

<jaxrs:server id="aegisbook" address="/aegis">
  <jaxrs:serviceBeans>
    <ref bean="serviceBean" />
  </jaxrs:serviceBeans>
  <jaxrs:dataBinding>
    <bean class="org.apache.cxf.aegis.databinding.AegisDatabinding">
      <property name="aegisContext">
        <bean class="org.apache.cxf.aegis.AegisContext">
          <property name="writeXsiTypes" value="true"/>
        </bean>
      </property>
    </bean>
  </jaxrs:dataBinding>
</jaxrs:server>
Using the JMS transport

It is possible to configure JAX-RS to use a JMS messaging library as a transport protocol, instead of HTTP. Because JMS itself is not a transport protocol, the actual messaging protocol depends on the particular JMS implementation that you configure.

For example, the following Spring XML example shows how to configure a JAX-RS server endpoint to use the JMS transport protocol:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:jms="http://cxf.apache.org/transports/jms"
       xmlns:jaxrs="http://cxf.apache.org/jaxrs"
       xsi:schemaLocation="
http://cxf.apache.org/transports/jms http://cxf.apache.org/schemas/configuration/jms.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://cxf.apache.org/jaxrs http://cxf.apache.org/schemas/jaxrs.xsd">

    <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"/>
    <bean id="ConnectionFactory" class="org.apache.activemq.ActiveMQConnectionFactory">
        <property name="brokerURL" value="tcp://localhost:${testutil.ports.EmbeddedJMSBrokerLauncher}" />
    </bean>

    <jaxrs:server xmlns:s="http://books.com"
    	serviceName="s:BookService"
    	transportId= "http://cxf.apache.org/transports/jms"
    	address="jms:queue:test.jmstransport.text?replyToName=test.jmstransport.response">
        <jaxrs:serviceBeans>
            <bean class="org.apache.cxf.systest.jaxrs.JMSBookStore"/>
        </jaxrs:serviceBeans>
    </jaxrs:server>

</beans>

Note the following points about the preceding example:

  • JMS implementation—the JMS implementation is provided by the ConnectionFactory bean, which instantiates an Apache ActiveMQ connection factory object. After you instantiate the connection factory, it is automatically installed as the default JMS implementation layer.
  • JMS conduit or destination object—Apache CXF implicitly instantiates a JMS conduit object (to represent a JMS consumer) or a JMS destination object (to represent a JMS provider). This object must be uniquely identified by a QName, which is defined through the attribute setttings xmlns:s="http://books.com" (defining the namespace prefix) and serviceName="s:BookService" (defining the QName).
  • Transport ID—to select the JMS transport, the transportId attribute must be set to http://cxf.apache.org/transports/jms.
  • JMS address—the jaxrs:server/@address attribute uses a standardized syntax to specify the JMS queue or JMS topic to send to. For details of this syntax, see https://tools.ietf.org/id/draft-merrick-jms-uri-06.txt.
Extension mappings and language mappings

A JAX-RS server endpoint can be configured so that it automatically maps a file suffix (appearing in the URL) to a MIME content type header, and maps a language suffix to a language type header. For example, consider a HTTP request of the following form:

GET /resource.xml

You can configure the JAX-RS server endpoint to map the .xml suffix automatically, as follows:

<jaxrs:server id="customerService" address="/">
  <jaxrs:serviceBeans>
    <bean class="org.apache.cxf.jaxrs.systests.CustomerService" />
  </jaxrs:serviceBeans>
  <jaxrs:extensionMappings>
    <entry key="json" value="application/json"/>
    <entry key="xml" value="application/xml"/>
  </jaxrs:extensionMappings>
</jaxrs:server>

When the preceding server endpoint receives the HTTP request, it automatically creates a new content type header of type, application/xml, and strips the .xml suffix from the resource URL.

For the language mapping, consider a HTTP request of the following form:

GET /resource.en

You can configure the JAX-RS server endpoint to map the .en suffix automatically, as follows:

<jaxrs:server id="customerService" address="/">
  <jaxrs:serviceBeans>
    <bean class="org.apache.cxf.jaxrs.systests.CustomerService" />
  </jaxrs:serviceBeans>
  <jaxrs:languageMappings>
     <entry key="en" value="en-gb"/>
  </jaxrs:languageMappings>
</jaxrs:server>

When the preceding server endpoint receives the HTTP request, it automatically creates a new accept language header with the value, en-gb, and strips the .en suffix from the resource URL.

18.1.2. jaxrs:server Attributes

Attributes

Table 18.1, “JAX-RS Server Endpoint Attributes” describes the attributes available on the jaxrs:server element.

Table 18.1. JAX-RS Server Endpoint Attributes
AttributeDescription

id

Specifies a unique identifier that other configuration elements can use to refer to the endpoint.

address

Specifies the address of an HTTP endpoint. This value will override the value specified in the services contract.

basePackages

(Spring only) Enables auto-discovery, by specifying a comma-separated list of Java packages, which are searched to discover JAX-RS root resource classes and/or JAX-RS provider classes.

beanNames

Specifies a space-separated list of bean IDs of JAX-RS root resource beans. In the context of Spring XML, it is possible to define a root resource beans' lifecycle by setting the scope attribute on the root resource bean element.

bindingId

Specifies the ID of the message binding the service uses. A list of valid binding IDs is provided in Chapter 23, Apache CXF Binding IDs.

bus

Specifies the ID of the Spring bean configuring the bus used to manage the service endpoint. This is useful when configuring several endpoints to use a common set of features.

docLocation

Specifies the location of an external WADL document.

modelRef

Specifies a model schema as a classpath resource (for example, a URL of the form classpath:/path/to/model.xml). For details of how to define a JAX-RS model schema, see Section 18.3, “Defining REST Services with the Model Schema”.

publish

Specifies if the service should be automatically published. If set to false, the developer must explicitly publish the endpoint.

publishedEndpointUrl

Specifies the URL base address, which gets inserted into the wadl:resources/@base attribute of the auto-generated WADL interface.

serviceAnnotation

(Spring only) Specifies the service annotation class name for auto-discovery in Spring. When used in combination with the basePackages property, this option restricts the collection of auto-discovered classes to include only the classes that are annotated by this annotation type. guess!! Is this correct?

serviceClass

Specifies the name of a JAX-RS root resource class (which implements a JAX-RS service). In this case, the class is instantiated by Apache CXF, not by Blueprint or Spring. If you want to instantiate the class in Blueprint or Spring, use the jaxrs:serviceBeans child element instead.

serviceName

Specifies the service QName (using the format ns:name) for the JAX-RS endpoint in the special case where a JMS transport is used. For details, see the section called “Using the JMS transport”.

staticSubresourceResolution

If true, disables dynamic resolution of static sub-resources. Default is false.

transportId

For selecting a non-standard transport layer (in place of HTTP). In particular, you can select the JMS transport by setting this property to http://cxf.apache.org/transports/jms. For details, see the section called “Using the JMS transport”.

abstract

(Spring only) Specifies if the bean is an abstract bean. Abstract beans act as parents for concrete bean definitions and are not instantiated. The default is false. Setting this to true instructs the bean factory not to instantiate the bean.

depends-on

(Spring only) Specifies a list of beans that the endpoint depends on being instantiated before the endpoint can be instantiated.

18.1.3. jaxrs:server Child Elements

Child elements

Table 18.2, “JAX-RS Server Endpoint Child Elements” describes the child elements of the jaxrs:server element.

Table 18.2. JAX-RS Server Endpoint Child Elements
ElementDescription

jaxrs:executor

Specifies a Java Executor (thread pool implementation) that is used for the service. This is specified using an embedded bean definition.

jaxrs:features

Specifies a list of beans that configure advanced features of Apache CXF. You can provide either a list of bean references or a list of embedded beans.

jaxrs:binding

Not used.

jaxrs:dataBinding

Specifies the class implementing the data binding used by the endpoint. This is specified using an embedded bean definition. For more details, see the section called “Specifying the data binding”.

jaxrs:inInterceptors

Specifies a list of interceptors that process inbound requests. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxrs:inFaultInterceptors

Specifies a list of interceptors that process inbound fault messages. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxrs:outInterceptors

Specifies a list of interceptors that process outbound replies. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxrs:outFaultInterceptors

Specifies a list of interceptors that process outbound fault messages. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxrs:invoker

Specifies an implementation of the org.apache.cxf.service.Invoker interface used by the service. [a]

jaxrs:serviceFactories

Provides you with the maximum degree of control over the lifecycle of the JAX-RS root resources associated with this endpoint. The children of this element (which must be instances of org.apache.cxf.jaxrs.lifecycle.ResourceProvider type) are used to create JAX-RS root resource instances.

jaxrs:properties

Specifies a Spring map of properties that are passed along to the endpoint. These properties can be used to control features like enabling MTOM support.

jaxrs:serviceBeans

The children of this element are instances of (bean element) or references to (ref element) JAX-RS root resources. Note that in this case the scope attribute (Spring only), if present in the bean element, is ignored.

jaxrs:modelBeans

Consists of a list of references to one or more org.apache.cxf.jaxrs.model.UserResource beans, which are the basic elements of a resource model (corresponding to jaxrs:resource elements). For details, see Section 18.3, “Defining REST Services with the Model Schema”.

jaxrs:model

Defines a resource model directly in this endpoint (that is, this jaxrs:model element can contain one or more jaxrs:resource elements). For details, see Section 18.3, “Defining REST Services with the Model Schema”.

jaxrs:providers

Enables you to register one or more custom JAX-RS providers with this endpoint. The children of this element are instances of (bean element) or references to (ref element) JAX-RS providers.

jaxrs:extensionMappings

When the URL of a REST invocation ends in a file extension, you can use this element to associate it automatically with a particular content type. For example, the .xml file extension could be associated with the application/xml content type. For details, see the section called “Extension mappings and language mappings”.

jaxrs:languageMappings

When the URL of a REST invocation ends in a language suffix, you can use this element to map this to a particular language. For example, the .en language suffix could be associated with the en-GB language. For details, see the section called “Extension mappings and language mappings”.

jaxrs:schemaLocations

Specifies one or more XML schemas used for validating XML message content. This element can contain one or more jaxrs:schemaLocation elements, each specifying the location of an XML schema file (usually as a classpath URL). For details, see the section called “Schema validation”.

jaxrs:resourceComparator

Enables you to register a custom resource comparator, which implements the algorithm used to match an incoming URL path to a particular resource class or method.

jaxrs:resourceClasses

(Blueprint only) Can be used instead of the jaxrs:server/@serviceClass attribute, if you want to create multiple resources from class names. The children of jaxrs:resourceClasses must be class elements with a name attribute set to the name of the resource class. In this case, the classes are instantiated by Apache CXF, not by Blueprint or Spring.

[a] The Invoker implementation controls how a service is invoked. For example, it controls whether each request is handled by a new instance of the service implementation or if state is preserved across invocations.

18.2. Configuring JAX-RS Client Endpoints

18.2.1. Defining a JAX-RS Client Endpoint

Injecting client proxies

The main point of instantiating a client proxy bean in an XML language (Blueprint XML or Spring XML) is in order to inject it into another bean, which can then use the client proxy to invoke the REST service. To create a client proxy bean in XML, use the jaxrs:client element.

Namespaces

The JAX-RS client endpoint is defined using a different XML namespace from the server endpoint. The following table shows which namespace to use for which XML language:

XML LanguageNamespace for client endpoint

Blueprint

http://cxf.apache.org/blueprint/jaxrs-client

Spring

http://cxf.apache.org/jaxrs-client

Basic client endpoint definition

The following example shows how to create a client proxy bean in Blueprint XML or Spring XML:

<jaxrs:client id="restClient"
       address="http://localhost:8080/test/services/rest"
       serviceClass="org.apache.cxf.systest.jaxrs.BookStoreJaxrsJaxws"/>

Where you must set the following attributes to define the basic client endpoint:

id
The bean ID of the client proxy can be used to inject the client proxy into other beans in your XML configuration.
address
The address attribute specifies the base URL of the REST invocations.
serviceClass
The serviceClass attribute provides a description of the REST service by specifying a root resource class (annotated by @Path). In fact, this is a server class, but it is not used directly by the client. The specified class is used only for its metadata (through Java reflection and JAX-RS annotations), which is used to construct the client proxy dynamically.
Specifying headers

You can add HTTP headers to the client proxy’s invocations using the jaxrs:headers child elements, as follows:

<jaxrs:client id="restClient"
       address="http://localhost:8080/test/services/rest"
       serviceClass="org.apache.cxf.systest.jaxrs.BookStoreJaxrsJaxws"
       inheritHeaders="true">
       <jaxrs:headers>
           <entry key="Accept" value="text/xml"/>
       </jaxrs:headers>
</jaxrs:client>

18.2.2. jaxrs:client Attributes

Attributes

Table 18.3, “JAX-RS Client Endpoint Attributes” describes the attributes available on the jaxrs:client element.

Table 18.3. JAX-RS Client Endpoint Attributes
AttributeDescription

address

Specifies the HTTP address of the endpoint where the consumer will make requests. This value overrides the value set in the contract.

bindingId

Specifies the ID of the message binding the consumer uses. A list of valid binding IDs is provided in Chapter 23, Apache CXF Binding IDs.

bus

Specifies the ID of the Spring bean configuring the bus managing the endpoint.

inheritHeaders

Specifies whether the headers set for this proxy will be inherited, if a subresource proxy is created from this proxy. Default is false.

username

Specifies the username used for simple username/password authentication.

password

Specifies the password used for simple username/password authentication.

modelRef

Specifies a model schema as a classpath resource (for example, a URL of the form classpath:/path/to/model.xml). For details of how to define a JAX-RS model schema, see Section 18.3, “Defining REST Services with the Model Schema”.

serviceClass

Specifies the name of a service interface or a resource class (that is annotated with @PATH), re-using it from the JAX-RS server implementation. In this case, the specified class is not invoked directly (it is actually a server class). The specified class is used only for its metadata (through Java reflection and JAX-RS annotations), which is used to construct the client proxy dynamically.

serviceName

Specifies the service QName (using the format ns:name) for the JAX-RS endpoint in the special case where a JMS transport is used. For details, see the section called “Using the JMS transport”.

threadSafe

Specifies whether or not the client proxy is thread-safe. Default is false.

transportId

For selecting a non-standard transport layer (in place of HTTP). In particular, you can select the JMS transport by setting this property to http://cxf.apache.org/transports/jms. For details, see the section called “Using the JMS transport”.

abstract

(Spring only) Specifies if the bean is an abstract bean. Abstract beans act as parents for concrete bean definitions and are not instantiated. The default is false. Setting this to true instructs the bean factory not to instantiate the bean.

depends-on

(Spring only) Specifies a list of beans that the endpoint depends on being instantiated before it can be instantiated.

18.2.3. jaxrs:client Child Elements

Child elements

Table 18.4, “JAX-RS Client Endpoint Child Elements” describes the child elements of the jaxrs:client element.

Table 18.4. JAX-RS Client Endpoint Child Elements
ElementDescription

jaxrs:executor

 

jaxrs:features

Specifies a list of beans that configure advanced features of Apache CXF. You can provide either a list of bean references or a list of embedded beans.

jaxrs:binding

Not used.

jaxrs:dataBinding

Specifies the class implementing the data binding used by the endpoint. This is specified using an embedded bean definition. For more details, see the section called “Specifying the data binding”.

jaxrs:inInterceptors

Specifies a list of interceptors that process inbound responses. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxrs:inFaultInterceptors

Specifies a list of interceptors that process inbound fault messages. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxrs:outInterceptors

Specifies a list of interceptors that process outbound requests. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxrs:outFaultInterceptors

Specifies a list of interceptors that process outbound fault messages. For more information see Part VII, “Developing Apache CXF Interceptors”.

jaxrs:properties

Specifies a map of properties that are passed to the endpoint.

jaxrs:providers

Enables you to register one or more custom JAX-RS providers with this endpoint. The children of this element are instances of (bean element) or references to (ref element) JAX-RS providers.

jaxrs:modelBeans

Consists of a list of references to one or more org.apache.cxf.jaxrs.model.UserResource beans, which are the basic elements of a resource model (corresponding to jaxrs:resource elements). For details, see Section 18.3, “Defining REST Services with the Model Schema”.

jaxrs:model

Defines a resource model directly in this endpoint (that is, a jaxrs:model element containing one or more jaxrs:resource elements). For details, see Section 18.3, “Defining REST Services with the Model Schema”.

jaxrs:headers

Used for setting headers on the outgoing message. For details, see the section called “Specifying headers”.

jaxrs:schemaLocations

Specifies one or more XML schemas used for validating XML message content. This element can contain one or more jaxrs:schemaLocation elements, each specifying the location of an XML schema file (usually as a classpath URL). For details, see the section called “Schema validation”.

18.3. Defining REST Services with the Model Schema

RESTful services without annotations

The JAX-RS model schema makes it possible to define RESTful services without annotating Java classes. That is, instead of adding annotations like @Path, @PathParam, @Consumes, @Produces, and so on, directly to a Java class (or interface), you can provide all of the relevant REST metadata in a separate XML file, using the model schema. This can be useful, for example, in cases where you are unable to modify the Java source that implements the service.

Example model schema

Example 18.1, “Sample JAX-RS Model Schema” shows an example of a model schema that defines service metadata for the BookStoreNoAnnotations root resource class.

Example 18.1. Sample JAX-RS Model Schema

<model xmlns="http://cxf.apache.org/jaxrs">
  <resource name="org.apache.cxf.systest.jaxrs.BookStoreNoAnnotations" path="bookstore"
    produces="application/json" consumes="application/json">
    <operation name="getBook" verb="GET" path="/books/{id}" produces="application/xml">
       <param name="id" type="PATH"/>
    </operation>
    <operation name="getBookChapter" path="/books/{id}/chapter">
       <param name="id" type="PATH"/>
    </operation>
    <operation name="updateBook" verb="PUT">
       <param name="book" type="REQUEST_BODY"/>
    </operation>
  </resource>
  <resource name="org.apache.cxf.systest.jaxrs.ChapterNoAnnotations">
    <operation name="getItself" verb="GET"/>
    <operation name="updateChapter" verb="PUT" consumes="application/xml">
        <param name="content" type="REQUEST_BODY"/>
    </operation>
  </resource>
</model>

Namespaces

The XML namespace that you use to define a model schema depends on whether you are defining the corresponding JAX-RS endpoint in Blueprint XML or in Spring XML. The following table shows which namespace to use for which XML language:

XML LanguageNamespace

Blueprint

http://cxf.apache.org/blueprint/jaxrs

Spring

http://cxf.apache.org/jaxrs

How to attach a model schema to an endpoint

To define and attach a model schema to an endpoint, perform the following steps:

  1. Define the model schema, using the appropriate XML namespace for your chosen injection platform (Blueprint XML or Spring XML).
  2. Add the model schema file to your project’s resources, so that the schema file is available on the classpath in the final package (JAR, WAR, or OSGi bundle file).

    Note

    Alternatively, it is also possible to embed a model schema directly into a JAX-RS endpoint, using the endpoint’s jaxrs:model child element.

  3. Configure the endpoint to use the model schema, by setting the endpoint’s modelRef attribute to the location of the model schema on the classpath (using a classpath URL).
  4. If necessary, instantiate the root resources explicitly, using the jaxrs:serviceBeans element. You can skip this step, if the model schema references root resource classes directly (instead of referencing base interfaces).

Configuration of model schema referencing a class

If the model schema applies directly to root resource classes, there is no need to define any root resource beans using the jaxrs:serviceBeans element, because the model schema automatically instantiates the root resource beans.

For example, given that customer-resources.xml is a model schema that associates metadata with customer resource classes, you could instantiate a customerService service endpoint as follows:

<jaxrs:server id="customerService"
              address="/customers"
              modelRef="classpath:/org/example/schemas/customer-resources.xml" />

Configuration of model schema referencing an interface

If the model schema applies to Java interfaces (which are the base interfaces of the root resources), you must instantiate the root resource classes using the jaxrs:serviceBeans element in the endpoint.

For example, given that customer-interfaces.xml is a model schema that associates metadata with customer interfaces, you could instantiate a customerService service endpoint as follows:

<jaxrs:server id="customerService"
              address="/customers"
              modelRef="classpath:/org/example/schemas/customer-interfaces.xml">
    <jaxrs:serviceBeans>
       <ref component-id="serviceBean" />
    </jaxrs:serviceBeans>
</jaxrs:server>

<bean id="serviceBean" class="service.CustomerService"/>

Model Schema Reference

A model schema is defined using the following XML elements:

model
Root element of the model schema. If you need to reference the model schema (for example, from a JAX-RS endpoint using the modelRef attribute), you should set the id attribute on this element.
model/resource

The resource element is used to associate metadata with a specific root resource class (or with a corresponding interface). You can define the following attributes on the resource element:

AttributeDescription +

name

The name of the resource class (or corresponding interface) to which this resource model is applied.

+

path

The component of the REST URL path that maps to this resource.

+

consumes

Specifies the content type (Internet media type) consumed by this resource—for example, application/xml or application/json.

+

produces

Specifies the content type (Internet media type) produced by this resource—for example, application/xml or application/json.

+

model/resource/operation

The operation element is used to associate metadata with Java methods. You can define the following attributes on an operation element:

AttributeDescription +

name

The name of the Java method to which this element is applied.

+

path

The component of the REST URL path that maps to this method. This attribute value can include parameter references, for example: path="/books/{id}/chapter", where {id} extracts the value of the id parameter from the path.

+

verb

Specifies the HTTP verb that maps to this method. Typically one of: GET, POST, PUT, or DELETE. If the HTTP verb is not specified, it is assumed that the Java method is a sub-resource locater, which returns a reference to a sub-resource object (where the sub-resource class must also be provided with metadata using a resource element).

+

consumes

Specifies the content type (Internet media type) consumed by this operation—for example, application/xml or application/json.

+

produces

Specifies the content type (Internet media type) produced by this operation—for example, application/xml or application/json.

+

oneway

If true, configures the operation to be oneway, meaning that no reply message is needed. Defaults to false.

+

model/resource/operation/param

The param element is used extract a value from the REST URL and inject it into one of the method parameters. You can define the following attributes on a param element:

AttributeDescription +

name

The name of the Java method parameter to which this element is applied.

+

type

Specifies how the parameter value is extracted from the REST URL or message. It can be set to one of the following values: PATH, QUERY, MATRIX, HEADER, COOKIE, FORM, CONTEXT, REQUEST_BODY.

+

defaultValue

Default value to inject into the parameter, in case a value could not be extracted from the REST URL or message.

+

encoded

If true, the parameter value is injected in its URI encoded form (that is, using %nn encoding). Default is false. For example, when extracting a parameter from the URL path, /name/Joe%20Bloggs with encoded set to true, the parameter is injected as Joe%20Bloggs; otherwise, the parameter would be injected as Joe Bloggs.

+

Chapter 19. Apache CXF Logging

Abstract

This chapter describes how to configure logging in the Apache CXF runtime.

19.1. Overview of Apache CXF Logging

Overview

Apache CXF uses the Java logging utility, java.util.logging. Logging is configured in a logging configuration file that is written using the standard java.util.Properties format. To run logging on an application, you can specify logging programmatically or by defining a property at the command that points to the logging configuration file when you start the application.

Default properties file

Apache CXF comes with a default logging.properties file, which is located in your InstallDir/etc directory. This file configures both the output destination for the log messages and the message level that is published. The default configuration sets the loggers to print message flagged with the WARNING level to the console. You can either use the default file without changing any of the configuration settings or you can change the configuration settings to suit your specific application.

Logging feature

Apache CXF includes a logging feature that can be plugged into your client or your service to enable logging. Example 19.1, “Configuration for Enabling Logging” shows the configuration to enable the logging feature.

Example 19.1. Configuration for Enabling Logging

<jaxws:endpoint...>
  <jaxws:features>
    <bean class="org.apache.cxf.feature.LoggingFeature"/>
  </jaxws:features>
</jaxws:endpoint>

For more information, see Section 19.6, “Logging Message Content”.

Where to begin?

To run a simple example of logging follow the instructions outlined in a Section 19.2, “Simple Example of Using Logging”.

For more information on how logging works in Apache CXF, read this entire chapter.

More information on java.util.logging

The java.util.logging utility is one of the most widely used Java logging frameworks. There is a lot of information available online that describes how to use and extend this framework. As a starting point, however, the following documents gives a good overview of java.util.logging:

19.2. Simple Example of Using Logging

Changing the log levels and output destination

To change the log level and output destination of the log messages in the wsdl_first sample application, complete the following steps:

  1. Run the sample server as described in the Running the demo using java section of the README.txt file in the InstallDir/samples/wsdl_first directory. Note that the server start command specifies the default logging.properties file, as follows:

    PlatformCommand +

    Windows

    start java -Djava.util.logging.config.file=%CXF_HOME%\etc\logging.properties demo.hw.server.Server

    +

    UNIX

    java -Djava.util.logging.config.file=$CXF_HOME/etc/logging.properties demo.hw.server.Server &

    +

    The default logging.properties file is located in the InstallDir/etc directory. It configures the Apache CXF loggers to print WARNING level log messages to the console. As a result, you see very little printed to the console.

  2. Stop the server as described in the README.txt file.
  3. Make a copy of the default logging.properties file, name it mylogging.properties file, and save it in the same directory as the default logging.properties file.
  4. Change the global logging level and the console logging levels in your mylogging.properties file to INFO by editing the following lines of configuration:

    .level= INFO
    java.util.logging.ConsoleHandler.level = INFO
  5. Restart the server using the following command:

    PlatformCommand +

    Windows

    start java -Djava.util.logging.config.file=%CXF_HOME%\etc\mylogging.properties demo.hw.server.Server

    +

    UNIX

    java -Djava.util.logging.config.file=$CXF_HOME/etc/mylogging.properties demo.hw.server.Server &

    +

    Because you configured the global logging and the console logger to log messages of level INFO, you see a lot more log messages printed to the console.

19.3. Default logging configuration file

19.3.1. Overview of Logging Configuration

The default logging configuration file, logging.properties, is located in the InstallDir/etc directory. It configures the Apache CXF loggers to print WARNING level messages to the console. If this level of logging is suitable for your application, you do not have to make any changes to the file before using it. You can, however, change the level of detail in the log messages. For example, you can change whether log messages are sent to the console, to a file or to both. In addition, you can specify logging at the level of individual packages.

Note

This section discusses the configuration properties that appear in the default logging.properties file. There are, however, many other java.util.logging configuration properties that you can set. For more information on the java.util.logging API, see the java.util.logging javadoc at: http://download.oracle.com/javase/1.5/docs/api/java/util/logging/package-summary.html.

19.3.2. Configuring Logging Output

Overview

The Java logging utility, java.util.logging, uses handler classes to output log messages. Table 19.1, “Java.util.logging Handler Classes” shows the handlers that are configured in the default logging.properties file.

Table 19.1. Java.util.logging Handler Classes
Handler ClassOutputs to

ConsoleHandler

Outputs log messages to the console

FileHandler

Outputs log messages to a file

Important

The handler classes must be on the system classpath in order to be installed by the Java VM when it starts. This is done when you set the Apache CXF environment.

Configuring the console handler

Example 19.2, “Configuring the Console Handler” shows the code for configuring the console logger.

Example 19.2. Configuring the Console Handler

handlers= java.util.logging.ConsoleHandler

The console handler also supports the configuration properties shown in Example 19.3, “Console Handler Properties”.

Example 19.3. Console Handler Properties

java.util.logging.ConsoleHandler.level = WARNING
java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter

The configuration properties shown in Example 19.3, “Console Handler Properties” can be explained as follows:

The console handler supports a separate log level configuration property. This allows you to limit the log messages printed to the console while the global logging setting can be different (see Section 19.3.3, “Configuring Logging Levels”). The default setting is WARNING.

Specifies the java.util.logging formatter class that the console handler class uses to format the log messages. The default setting is the java.util.logging.SimpleFormatter.

Configuring the file handler

Example 19.4, “Configuring the File Handler” shows code that configures the file handler.

Example 19.4. Configuring the File Handler

handlers= java.util.logging.FileHandler

The file handler also supports the configuration properties shown in Example 19.5, “File Handler Configuration Properties”.

Example 19.5. File Handler Configuration Properties

java.util.logging.FileHandler.pattern = %h/java%u.log
java.util.logging.FileHandler.limit = 50000
java.util.logging.FileHandler.count = 1
java.util.logging.FileHandler.formatter = java.util.logging.XMLFormatter

The configuration properties shown in Example 19.5, “File Handler Configuration Properties” can be explained as follows:

Specifies the location and pattern of the output file. The default setting is your home directory.

Specifies, in bytes, the maximum amount that the logger writes to any one file. The default setting is 50000. If you set it to zero, there is no limit on the amount that the logger writes to any one file.

Specifies how many output files to cycle through. The default setting is 1.

Specifies the java.util.logging formatter class that the file handler class uses to format the log messages. The default setting is the java.util.logging.XMLFormatter.

Configuring both the console handler and the file handler

You can set the logging utility to output log messages to both the console and to a file by specifying the console handler and the file handler, separated by a comma, as shown in Configuring Both Console Logging and File.

Configuring Both Console Logging and File

Logging

handlers= java.util.logging.FileHandler, java.util.logging.ConsoleHandler

19.3.3. Configuring Logging Levels

Logging levels

The java.util.logging framework supports the following levels of logging, from the least verbose to the most verbose:

  • SEVERE
  • WARNING
  • INFO
  • CONFIG
  • FINE
  • FINER
  • FINEST
Configuring the global logging level

To configure the types of event that are logged across all loggers, configure the global logging level as shown in Example 19.6, “Configuring Global Logging Levels”.

Example 19.6. Configuring Global Logging Levels

.level= WARNING
Configuring logging at an individual package
level

The java.util.logging framework supports configuring logging at the level of an individual package. For example, the line of code shown in Example 19.7, “Configuring Logging at the Package Level” configures logging at a SEVERE level on classes in the com.xyz.foo package.

Example 19.7. Configuring Logging at the Package Level

com.xyz.foo.level = SEVERE

19.4. Enabling Logging at the Command Line

Overview

You can run the logging utility on an application by defining a java.util.logging.config.file property when you start the application. You can either specify the default logging.properties file or a logging.properties file that is unique to that application.

Specifying the log configuration file on application

start-up

To specify logging on application start-up add the flag shown in Example 19.8, “Flag to Start Logging on the Command Line” when starting the application.

Example 19.8. Flag to Start Logging on the Command Line

-Djava.util.logging.config.file=myfile

19.5. Logging for Subsystems and Services

Overview

You can use the com.xyz.foo.level configuration property described in the section called “Configuring logging at an individual package” to set fine-grained logging for specified Apache CXF logging subsystems.

Apache CXF logging subsystems

Table 19.2, “Apache CXF Logging Subsystems” shows a list of available Apache CXF logging subsystems.

Table 19.2. Apache CXF Logging Subsystems
SubsystemDescription

org.apache.cxf.aegis

Aegis binding

org.apache.cxf.binding.coloc

colocated binding

org.apache.cxf.binding.http

HTTP binding

org.apache.cxf.binding.jbi

JBI binding

org.apache.cxf.binding.object

Java Object binding

org.apache.cxf.binding.soap

SOAP binding

org.apache.cxf.binding.xml

XML binding

org.apache.cxf.bus

Apache CXF bus

org.apache.cxf.configuration

configuration framework

org.apache.cxf.endpoint

server and client endpoints

org.apache.cxf.interceptor

interceptors

org.apache.cxf.jaxws

Front-end for JAX-WS style message exchange, JAX-WS handler processing, and interceptors relating to JAX-WS and configuration

org.apache.cxf.jbi

JBI container integration classes

org.apache.cxf.jca

JCA container integration classes

org.apache.cxf.js

JavaScript front-end

org.apache.cxf.transport.http

HTTP transport

org.apache.cxf.transport.https

secure version of HTTP transport, using HTTPS

org.apache.cxf.transport.jbi

JBI transport

org.apache.cxf.transport.jms

JMS transport

org.apache.cxf.transport.local

transport implementation using local file system

org.apache.cxf.transport.servlet

HTTP transport and servlet implementation for loading JAX-WS endpoints into a servlet container

org.apache.cxf.ws.addressing

WS-Addressing implementation

org.apache.cxf.ws.policy

WS-Policy implementation

org.apache.cxf.ws.rm

WS-ReliableMessaging (WS-RM) implementation

org.apache.cxf.ws.security.wss4j

WSS4J security implementation

Example

The WS-Addressing sample is contained in the InstallDir/samples/ws_addressing directory. Logging is configured in the logging.properties file located in that directory. The relevant lines of configuration are shown in Example 19.9, “Configuring Logging for WS-Addressing”.

Example 19.9. Configuring Logging for WS-Addressing

java.util.logging.ConsoleHandler.formatter = demos.ws_addressing.common.ConciseFormatter
...
org.apache.cxf.ws.addressing.soap.MAPCodec.level = INFO

The configuration in Example 19.9, “Configuring Logging for WS-Addressing” enables the snooping of log messages relating to WS-Addressing headers, and displays them to the console in a concise form.

For information on running this sample, see the README.txt file located in the InstallDir/samples/ws_addressing directory.

19.6. Logging Message Content

Overview

You can log the content of the messages that are sent between a service and a consumer. For example, you might want to log the contents of SOAP messages that are being sent between a service and a consumer.

Configuring message content logging

To log the messages that are sent between a service and a consumer, and vice versa, complete the following steps:

Adding the logging feature to an endpoint

Add the logging feature your endpoint’s configuration as shown in Example 19.10, “Adding Logging to Endpoint Configuration”.

Example 19.10. Adding Logging to Endpoint Configuration

<jaxws:endpoint ...>
  <jaxws:features>
    <bean class="org.apache.cxf.feature.LoggingFeature"/>
  </jaxws:features>
</jaxws:endpoint>

The example XML shown in Example 19.10, “Adding Logging to Endpoint Configuration” enables the logging of SOAP messages.

Adding the logging feature to a consumer

Add the logging feature your client’s configuration as shown in Example 19.11, “Adding Logging to Client Configuration”.

Example 19.11. Adding Logging to Client Configuration

<jaxws:client ...>
   <jaxws:features>
      <bean class="org.apache.cxf.feature.LoggingFeature"/>
    </jaxws:features>
</jaxws:client>

The example XML shown in Example 19.11, “Adding Logging to Client Configuration” enables the logging of SOAP messages.

Set logging to log INFO level messages

Ensure that the logging.properties file associated with your service is configured to log INFO level messages, as shown in Example 19.12, “Setting the Logging Level to INFO”.

Example 19.12. Setting the Logging Level to INFO

.level= INFO
java.util.logging.ConsoleHandler.level = INFO

Logging SOAP messages

To see the logging of SOAP messages modify the wsdl_first sample application located in the InstallDir/samples/wsdl_first directory, as follows:

  1. Add the jaxws:features element shown in Example 19.13, “Endpoint Configuration for Logging SOAP Messages” to the cxf.xml configuration file located in the wsdl_first sample’s directory:

    Example 19.13. Endpoint Configuration for Logging SOAP Messages

    <jaxws:endpoint name="{http://apache.org/hello_world_soap_http}SoapPort"
                    createdFromAPI="true">
      <jaxws:properties>
        <entry key="schema-validation-enabled" value="true" />
      </jaxws:properties>
      <jaxws:features>
        <bean class="org.apache.cxf.feature.LoggingFeature"/>
      </jaxws:features>
    </jaxws:endpoint>
  2. The sample uses the default logging.properties file, which is located in the InstallDir/etc directory. Make a copy of this file and name it mylogging.properties.
  3. In the mylogging.properties file, change the logging levels to INFO by editing the .level and the java.util.logging.ConsoleHandler.level configuration properties as follows:

    .level= INFO
    java.util.logging.ConsoleHandler.level = INFO
  4. Start the server using the new configuration settings in both the cxf.xml file and the mylogging.properties file as follows:

    PlatformCommand +

    Windows

    start java -Djava.util.logging.config.file=%CXF_HOME%\etc\mylogging.properties demo.hw.server.Server

    +

    UNIX

    java -Djava.util.logging.config.file=$CXF_HOME/etc/mylogging.properties demo.hw.server.Server &

    +

  5. Start the hello world client using the following command:

    PlatformCommand +

    Windows

    java -Djava.util.logging.config.file=%CXF_HOME%\etc\mylogging.properties demo.hw.client.Client .\wsdl\hello_world.wsdl

    +

    UNIX

    java -Djava.util.logging.config.file=$CXF_HOME/etc/mylogging.properties demo.hw.client.Client ./wsdl/hello_world.wsdl

    +

The SOAP messages are logged to the console.

Chapter 20. Deploying WS-Addressing

Abstract

Apache CXF supports WS-Addressing for JAX-WS applications. This chapter explains how to deploy WS-Addressing in the Apache CXF runtime environment.

20.1. Introduction to WS-Addressing

Overview

WS-Addressing is a specification that allows services to communicate addressing information in a transport neutral way. It consists of two parts:

  • A structure for communicating a reference to a Web service endpoint
  • A set of Message Addressing Properties (MAP) that associate addressing information with a particular message

Supported specifications

Apache CXF supports both the WS-Addressing 2004/08 specification and the WS-Addressing 2005/03 specification.

Further information

For detailed information on WS-Addressing, see the 2004/08 submission at http://www.w3.org/Submission/ws-addressing/.

20.2. WS-Addressing Interceptors

Overview

In Apache CXF, WS-Addressing functionality is implemented as interceptors. The Apache CXF runtime uses interceptors to intercept and work with the raw messages that are being sent and received. When a transport receives a message, it creates a message object and sends that message through an interceptor chain. If the WS-Addressing interceptors are added to the application’s interceptor chain, any WS-Addressing information included with a message is processed.

WS-Addressing Interceptors

The WS-Addressing implementation consists of two interceptors, as described in Table 20.1, “WS-Addressing Interceptors”.

Table 20.1. WS-Addressing Interceptors
InterceptorDescription

org.apache.cxf.ws.addressing.MAPAggregator

A logical interceptor responsible for aggregating the Message Addressing Properties (MAPs) for outgoing messages.

org.apache.cxf.ws.addressing.soap.MAPCodec

A protocol-specific interceptor responsible for encoding and decoding the Message Addressing Properties (MAPs) as SOAP headers.

20.3. Enabling WS-Addressing

Overview

To enable WS-Addressing the WS-Addressing interceptors must be added to the inbound and outbound interceptor chains. This is done in one of the following ways:

  • Apache CXF Features
  • RMAssertion and WS-Policy Framework
  • Using Policy Assertion in a WS-Addressing Feature

Adding WS-Addressing as a Feature

WS-Addressing can be enabled by adding the WS-Addressing feature to the client and the server configuration as shown in Example 20.1, “client.xml and Adding WS-Addressing Feature to Client Configuration” and Example 20.2, “server.xml and Adding WS-Addressing Feature to Server Configuration” respectively.

Example 20.1. client.xml and Adding WS-Addressing Feature to Client Configuration

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:jaxws="http://cxf.apache.org/jaxws"
       xmlns:wsa="http://cxf.apache.org/ws/addressing"
       xsi:schemaLocation="
          http://www.springframework.org/schema/beans
          http://www.springframework.org/schema/beans/spring-beans.xsd
          http://cxf.apache.org/ws/addressing
          http://cxf.apache.org/schemas/ws-addr-conf.xsd">

    <jaxws:client ...>
        <jaxws:features>
            <wsa:addressing/>
        </jaxws:features>
    </jaxws:client>
</beans>

Example 20.2. server.xml and Adding WS-Addressing Feature to Server Configuration

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:jaxws="http://cxf.apache.org/jaxws"
       xmlns:wsa="http://cxf.apache.org/ws/addressing"
       xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <jaxws:endpoint ...>
        <jaxws:features>
            <wsa:addressing/>
        </jaxws:features>
    </jaxws:endpoint>
</beans>

20.4. Configuring WS-Addressing Attributes

Overview

The Apache CXF WS-Addressing feature element is defined in the namespace http://cxf.apache.org/ws/addressing. It supports the two attributes described in Table 20.2, “WS-Addressing Attributes”.

Table 20.2. WS-Addressing Attributes
Attribute NameValue

allowDuplicates

A boolean that determines if duplicate MessageIDs are tolerated. The default setting is true.

usingAddressingAdvisory

A boolean that indicates if the presence of the UsingAddressing element in the WSDL is advisory only; that is, its absence does not prevent the encoding of WS-Addressing headers.

Configuring WS-Addressing attributes

Configure WS-Addressing attributes by adding the attribute and the value you want to set it to the WS-Addressing feature in your server or client configuration file. For example, the following configuration extract sets the allowDuplicates attribute to false on the server endpoint:

<beans ... xmlns:wsa="http://cxf.apache.org/ws/addressing" ...>
    <jaxws:endpoint ...>
        <jaxws:features>
            <wsa:addressing allowDuplicates="false"/>
        </jaxws:features>
    </jaxws:endpoint>
</beans>

Using a WS-Policy assertion embedded in a feature

In Example 20.3, “Using the Policies to Configure WS-Addressing” an addressing policy assertion to enable non-anonymous responses is embedded in the policies element.

Example 20.3. Using the Policies to Configure WS-Addressing

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:wsa="http://cxf.apache.org/ws/addressing"
        xmlns:wsp="http://www.w3.org/2006/07/ws-policy"
        xmlns:policy="http://cxf.apache.org/policy-config"
        xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"
        xmlns:jaxws="http://cxf.apache.org/jaxws"
        xsi:schemaLocation="
http://www.w3.org/2006/07/ws-policy http://www.w3.org/2006/07/ws-policy.xsd
http://cxf.apache.org/ws/addressing http://cxf.apache.org/schema/ws/addressing.xsd
http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <jaxws:endpoint name="{http://cxf.apache.org/greeter_control}GreeterPort"
                    createdFromAPI="true">
        <jaxws:features>
            <policy:policies>
                <wsp:Policy xmlns:wsam="http://www.w3.org/2007/02/addressing/metadata">
                    <wsam:Addressing>
                        <wsp:Policy>
                            <wsam:NonAnonymousResponses/>
                        </wsp:Policy>
                    </wsam:Addressing>
                </wsp:Policy>
            <policy:policies>
        </jaxws:features>
    </jaxws:endpoint>
</beans>

Chapter 21. Enabling Reliable Messaging

Abstract

Apache CXF supports WS-Reliable Messaging(WS-RM). This chapter explains how to enable and configure WS-RM in Apache CXF.

21.1. Introduction to WS-RM

Overview

WS-ReliableMessaging (WS-RM) is a protocol that ensures the reliable delivery of messages in a distributed environment. It enables messages to be delivered reliably between distributed applications in the presence of software, system, or network failures.

For example, WS-RM can be used to ensure that the correct messages have been delivered across a network exactly once, and in the correct order.

How WS-RM works

WS-RM ensures the reliable delivery of messages between a source and a destination endpoint. The source is the initial sender of the message and the destination is the ultimate receiver, as shown in Figure 21.1, “Web Services Reliable Messaging”.

Figure 21.1. Web Services Reliable Messaging

reliable message exchange

The flow of WS-RM messages can be described as follows:

  1. The RM source sends a CreateSequence protocol message to the RM destination. This contains a reference for the endpoint that receives acknowledgements (the wsrm:AcksTo endpoint).
  2. The RM destination sends a CreateSequenceResponse protocol message back to the RM source. This message contains the sequence ID for the RM sequence session.
  3. The RM source adds an RM Sequence header to each message sent by the application source. This header contains the sequence ID and a unique message ID.
  4. The RM source transmits each message to the RM destination.
  5. The RM destination acknowledges the receipt of the message from the RM source by sending messages that contain the RM SequenceAcknowledgement header.
  6. The RM destination delivers the message to the application destination in an exactly-once-in-order fashion.
  7. The RM source retransmits a message that it has not yet received an acknowledgement.

    The first retransmission attempt is made after a base retransmission interval. Successive retransmission attempts are made, by default, at exponential back-off intervals or, alternatively, at fixed intervals. For more details, see Section 21.5, “Configuring WS-RM”.

This entire process occurs symmetrically for both the request and the response message; that is, in the case of the response message, the server acts as the RM source and the client acts as the RM destination.

WS-RM delivery assurances

WS-RM guarantees reliable message delivery in a distributed environment, regardless of the transport protocol used. Either the source or the destination endpoint logs an error if reliable delivery can not be assured.

Supported specifications

Apache CXF supports the following versions of the WS-RM specification:

WS-ReliableMessaging 1.0

(Default) Corresponds to the February 2005 submission version, which is now out of date. For reasons of backward compatibility, however, this version is used as the default.

Version 1.0 of WS-RM uses the following namespace:

http://schemas.xmlsoap.org/ws/2005/02/rm/

This version of WS-RM can be used with either of the following WS-Addressing versions:

http://schemas.xmlsoap.org/ws/2004/08/addressing (default)
http://www.w3.org/2005/08/addressing

Strictly speaking, in order to comply with the February 2005 submission version of WS-RM, you ought to use the first of these WS-Addressing versions (which is the default in Apache CXF). But most other Web service implementations have switched to the more recent WS-Addressing specification, so Apache CXF allows you to choose the WS-A version, to facilitate interoperability (see Section 21.4, “Runtime Control”).

WS-ReliableMessaging 1.1/1.2

Corresponds to the official 1.1/1.2 Web Services Reliable Messaging specification.

Versions 1.1 and 1.2 of WS-RM uses the following namespace:

http://docs.oasis-open.org/ws-rx/wsrm/200702

The 1.1 and 1.2 versions of WS-RM use the following WS-Addressing version:

http://www.w3.org/2005/08/addressing

Selecting the WS-RM version

You can select which WS-RM specification version to use, as follows:

Server side
On the provider side, Apache CXF adapts to whichever version of WS-ReliableMessaging is used by the client and responds appropriately.
Client side
On the client side, the WS-RM version is determined either by the namespace that you use in the client configuration (see Section 21.5, “Configuring WS-RM”) or by overriding the WS-RM version at run time, using the runtime control options (see Section 21.4, “Runtime Control”).

21.2. WS-RM Interceptors

Overview

In Apache CXF, WS-RM functionality is implemented as interceptors. The Apache CXF runtime uses interceptors to intercept and work with the raw messages that are being sent and received. When a transport receives a message, it creates a message object and sends that message through an interceptor chain. If the application’s interceptor chain includes the WS-RM interceptors, the application can participate in reliable messaging sessions. The WS-RM interceptors handle the collection and aggregation of the message chunks. They also handle all of the acknowledgement and retransmission logic.

Apache CXF WS-RM Interceptors

The Apache CXF WS-RM implementation consists of four interceptors, which are described in Table 21.1, “Apache CXF WS-ReliableMessaging Interceptors”.

Table 21.1. Apache CXF WS-ReliableMessaging Interceptors
InterceptorDescription

org.apache.cxf.ws.rm.RMOutInterceptor

Deals with the logical aspects of providing reliability guarantees for outgoing messages.

Responsible for sending the CreateSequence requests and waiting for their CreateSequenceResponse responses.

Also responsible for aggregating the sequence properties—ID and message number—for an application message.

org.apache.cxf.ws.rm.RMInInterceptor

Responsible for intercepting and processing RM protocol messages and SequenceAcknowledgement messages that are piggybacked on application messages.

org.apache.cxf.ws.rm.RMCaptureInInterceptor

Caching incoming messages for persistent storage.

org.apache.cxf.ws.rm.RMDeliveryInterceptor

Assuring InOrder delivery of messages to the application.

org.apache.cxf.ws.rm.soap.RMSoapInterceptor

Responsible for encoding and decoding the reliability properties as SOAP headers.

org.apache.cxf.ws.rm.RetransmissionInterceptor

Responsible for creating copies of application messages for future resending.

Enabling WS-RM

The presence of the WS-RM interceptors on the interceptor chains ensures that WS-RM protocol messages are exchanged when necessary. For example, when intercepting the first application message on the outbound interceptor chain, the RMOutInterceptor sends a CreateSequence request and waits to process the original application message until it receives the CreateSequenceResponse response. In addition, the WS-RM interceptors add the sequence headers to the application messages and, on the destination side, extract them from the messages. It is not necessary to make any changes to your application code to make the exchange of messages reliable.

For more information on how to enable WS-RM, see Section 21.3, “Enabling WS-RM”.

Configuring WS-RM Attributes

You control sequence demarcation and other aspects of the reliable exchange through configuration. For example, by default Apache CXF attempts to maximize the lifetime of a sequence, thus reducing the overhead incurred by the out-of-band WS-RM protocol messages. To enforce the use of a separate sequence per application message configure the WS-RM source’s sequence termination policy (setting the maximum sequence length to 1).

For more information on configuring WS-RM behavior, see Section 21.5, “Configuring WS-RM”.

21.3. Enabling WS-RM

Overview

To enable reliable messaging, the WS-RM interceptors must be added to the interceptor chains for both inbound and outbound messages and faults. Because the WS-RM interceptors use WS-Addressing, the WS-Addressing interceptors must also be present on the interceptor chains.

You can ensure the presence of these interceptors in one of two ways:

  • Explicitly, by adding them to the dispatch chains using Spring beans
  • Implicitly, using WS-Policy assertions, which cause the Apache CXF runtime to transparently add the interceptors on your behalf.

Spring beans: explicitly adding interceptors

To enable WS-RM add the WS-RM and WS-Addressing interceptors to the Apache CXF bus, or to a consumer or service endpoint using Spring bean configuration. This is the approach taken in the WS-RM sample that is found in the InstallDir/samples/ws_rm directory. The configuration file, ws-rm.cxf, shows the WS-RM and WS-Addressing interceptors being added one-by-one as Spring beans (see Example 21.1, “Enabling WS-RM Using Spring Beans”).

Example 21.1. Enabling WS-RM Using Spring Beans

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/
   beans http://www.springframework.org/schema/beans/spring-beans.xsd">
   <bean id="mapAggregator" class="org.apache.cxf.ws.addressing.MAPAggregator"/>
   <bean id="mapCodec" class="org.apache.cxf.ws.addressing.soap.MAPCodec"/>
   <bean id="rmLogicalOut" class="org.apache.cxf.ws.rm.RMOutInterceptor">
        <property name="bus" ref="cxf"/>
   </bean>
   <bean id="rmLogicalIn" class="org.apache.cxf.ws.rm.RMInInterceptor">
        <property name="bus" ref="cxf"/>
   </bean>
   <bean id="rmCodec" class="org.apache.cxf.ws.rm.soap.RMSoapInterceptor"/>
   <bean id="cxf" class="org.apache.cxf.bus.CXFBusImpl">
        <property name="inInterceptors">
            <list>
                <ref bean="mapAggregator"/>
                <ref bean="mapCodec"/>
                <ref bean="rmLogicalIn"/>
                <ref bean="rmCodec"/>
            </list>
        </property>
        <property name="inFaultInterceptors">
            <list>
                <ref bean="mapAggregator"/>
                <ref bean="mapCodec"/>
                <ref bean="rmLogicalIn"/>
                <ref bean="rmCodec"/>
            </list>
        </property>
        <property name="outInterceptors">
            <list>
                <ref bean="mapAggregator"/>
                <ref bean="mapCodec"/>
                <ref bean="rmLogicalOut"/>
                <ref bean="rmCodec"/>
            </list>
        </property>
        <property name="outFaultInterceptors">
            <list>
                <ref bean="mapAggregator">
                <ref bean="mapCodec"/>
                <ref bean="rmLogicalOut"/>
                <ref bean="rmCodec"/>
            </list>
        </property>
    </bean>
</beans>

The code shown in Example 21.1, “Enabling WS-RM Using Spring Beans” can be explained as follows:

A Apache CXF configuration file is a Spring XML file. You must include an opening Spring beans element that declares the namespaces and schema files for the child elements that are encapsulated by the beans element.

Configures each of the WS-Addressing interceptors—MAPAggregator and MAPCodec. For more information on WS-Addressing, see Chapter 20, Deploying WS-Addressing.

Configures each of the WS-RM interceptors—RMOutInterceptor, RMInInterceptor, and RMSoapInterceptor.

Adds the WS-Addressing and WS-RM interceptors to the interceptor chain for inbound messages.

Adds the WS-Addressing and WS-RM interceptors to the interceptor chain for inbound faults.

Adds the WS-Addressing and WS-RM interceptors to the interceptor chain for outbound messages.

Adds the WS-Addressing and WS-RM interceptors to the interceptor chain for outbound faults.

WS-Policy framework: implicitly adding interceptors

The WS-Policy framework provides the infrastructure and APIs that allow you to use WS-Policy. It is compliant with the November 2006 draft publications of the Web Services Policy 1.5—Framework and Web Services Policy 1.5—Attachment specifications.

To enable WS-RM using the Apache CXF WS-Policy framework, do the following:

  1. Add the policy feature to your client and server endpoint. Example 21.2, “Configuring WS-RM using WS-Policy” shows a reference bean nested within a jaxws:feature element. The reference bean specifies the AddressingPolicy, which is defined as a separate element within the same configuration file.

    Example 21.2. Configuring WS-RM using WS-Policy

    <jaxws:client>
        <jaxws:features>
          <ref bean="AddressingPolicy"/>
        </jaxws:features>
    </jaxws:client>
    <wsp:Policy wsu:Id="AddressingPolicy" xmlns:wsam="http://www.w3.org/2007/02/addressing/metadata">
        <wsam:Addressing>
          <wsp:Policy>
            <wsam:NonAnonymousResponses/>
          </wsp:Policy>
        </wsam:Addressing>
    </wsp:Policy>
  2. Add a reliable messaging policy to the wsdl:service element—or any other WSDL element that can be used as an attachment point for policy or policy reference elements—to your WSDL file, as shown in Example 21.3, “Adding an RM Policy to Your WSDL File”.

    Example 21.3. Adding an RM Policy to Your WSDL File

    <wsp:Policy wsu:Id="RM"
       xmlns:wsp="http://www.w3.org/2006/07/ws-policy"
       xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd">
        <wsam:Addressing xmlns:wsam="http://www.w3.org/2007/02/addressing/metadata">
            <wsp:Policy/>
        </wsam:Addressing>
        <wsrmp:RMAssertion xmlns:wsrmp="http://schemas.xmlsoap.org/ws/2005/02/rm/policy">
            <wsrmp:BaseRetransmissionInterval Milliseconds="10000"/>
        </wsrmp:RMAssertion>
    </wsp:Policy>
    ...
    <wsdl:service name="ReliableGreeterService">
        <wsdl:port binding="tns:GreeterSOAPBinding" name="GreeterPort">
            <soap:address location="http://localhost:9020/SoapContext/GreeterPort"/>
            <wsp:PolicyReference URI="#RM" xmlns:wsp="http://www.w3.org/2006/07/ws-policy"/>
        </wsdl:port>
    </wsdl:service>

21.4. Runtime Control

Overview

Several message context property values can be set in client code to control WS-RM at runtime, with key values defined by public constants in the org.apache.cxf.ws.rm.RMManager class.

Runtime control options

The following table lists the keys defined by the org.apache.cxf.ws.rm.RMManager class.

KeyDescription

WSRM_VERSION_PROPERTY

String WS-RM version namespace (http://schemas.xmlsoap.org/ws/2005/02/rm/ or http://docs.oasis-open.org/ws-rx/wsrm/200702).

WSRM_WSA_VERSION_PROPERTY

String WS-Addressing version namespace (http://schemas.xmlsoap.org/ws/2004/08/addressing or http://www.w3.org/2005/08/addressing) - this property is ignored unless you’re using the http://schemas.xmlsoap.org/ws/2005/02/rm/ RM namespace).

WSRM_LAST_MESSAGE_PROPERTY

Boolean value true to tell the WS-RM code that the last message is being sent, allowing the code to close the WS-RM sequence and release resources (as of the 3.0.0 version of CXF, the WS-RM will close the RM sequence by default, when you close your client).

WSRM_INACTIVITY_TIMEOUT_PROPERTY

Long inactivity timeout in milliseconds.

WSRM_RETRANSMISSION_INTERVAL_PROPERTY

Long base retransmission interval in milliseconds.

WSRM_EXPONENTIAL_BACKOFF_PROPERTY

Boolean exponential back-off flag.

WSRM_ACKNOWLEDGEMENT_INTERVAL_PROPERTY

Long acknowledgement interval in milliseconds.

Controlling WS-RM through JMX

You can also monitor and control many aspects of WS-RM using the JMX Management features of Apache CXF. The full list of JMX operations is defined by org.apache.cxf.ws.rm.ManagedRMManager and org.apache.cxf.ws.rm.ManagedRMEndpoint, but these operations include viewing the current RM state down to the individual message level. You can also use JXM to close or terminate a WS-RM sequence, and to receive notification of when previously-sent messages are acknowledged by the remote RM endpoint.

Example of JMX control

For example, if you have the JMX server enabled in your client configuration, you could use the following code to track the last acknowledgement number received:

// Java
private static class AcknowledgementListener implements NotificationListener {
    private volatile long lastAcknowledgement;

    @Override
    public void handleNotification(Notification notification, Object handback) {
        if (notification instanceof AcknowledgementNotification) {
            AcknowledgementNotification ack = (AcknowledgementNotification)notification;
            lastAcknowledgement = ack.getMessageNumber();
        }
    }

    // initialize client
...
    // attach to JMX bean for notifications
    //  NOTE: you must have sent at least one message to initialize RM before executing this code
    Endpoint ep = ClientProxy.getClient(client).getEndpoint();
    InstrumentationManager im = bus.getExtension(InstrumentationManager.class);
    MBeanServer mbs = im.getMBeanServer();
    RMManager clientManager = bus.getExtension(RMManager.class);
    ObjectName name = RMUtils.getManagedObjectName(clientManager, ep);
    System.out.println("Looking for endpoint name " + name);
    AcknowledgementListener listener = new AcknowledgementListener();
    mbs.addNotificationListener(name, listener, null, null);

    // send messages using RM with acknowledgement status reported to listener
...

21.5. Configuring WS-RM

21.5.1. Configuring Apache CXF-Specific WS-RM Attributes

Overview

To configure the Apache CXF-specific attributes, use the rmManager Spring bean. Add the following to your configuration file:

Example 21.4, “Configuring Apache CXF-Specific WS-RM Attributes” shows a simple example.

Example 21.4. Configuring Apache CXF-Specific WS-RM Attributes

&lt;beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager"
      xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
 http://cxf.apache.org/ws/rm/manager http://cxf.apache.org/schemas/configuration/wsrm-manager.xsd"&gt;
...
&lt;wsrm-mgr:rmManager&gt;
&lt;!--
  ...Your configuration goes here
--&gt;
&lt;/wsrm-mgr:rmManager&gt;
Children of the rmManager Spring bean

Table 21.2, “Children of the rmManager Spring Bean” shows the child elements of the rmManager Spring bean, defined in the http://cxf.apache.org/ws/rm/manager namespace.

Table 21.2. Children of the rmManager Spring Bean
ElementDescription

RMAssertion

An element of type RMAssertion

deliveryAssurance

An element of type DeliveryAssuranceType that describes the delivery assurance that should apply

sourcePolicy

An element of type SourcePolicyType that allows you to configure details of the RM source

destinationPolicy

An element of type DestinationPolicyType that allows you to configure details of the RM destination

Example

For an example, see the section called “Maximum unacknowledged messages threshold”.

21.5.2. Configuring Standard WS-RM Policy Attributes

Overview

You can configure standard WS-RM policy attributes in one of the following ways:

WS-Policy RMAssertion Children

Table 21.3, “Children of the WS-Policy RMAssertion Element” shows the elements defined in the http://schemas.xmlsoap.org/ws/2005/02/rm/policy namespace:

Table 21.3. Children of the WS-Policy RMAssertion Element
NameDescription

InactivityTimeout

Specifies the amount of time that must pass without receiving a message before an endpoint can consider an RM sequence to have been terminated due to inactivity.

BaseRetransmissionInterval

Sets the interval within which an acknowledgement must be received by the RM Source for a given message. If an acknowledgement is not received within the time set by the BaseRetransmissionInterval, the RM Source will retransmit the message.

ExponentialBackoff

Indicates the retransmission interval will be adjusted using the commonly known exponential backoff algorithm (Tanenbaum).

For more information, see Computer Networks, Andrew S. Tanenbaum, Prentice Hall PTR, 2003.

AcknowledgementInterval

In WS-RM, acknowledgements are sent on return messages or sent stand-alone. If a return message is not available to send an acknowledgement, an RM Destination can wait for up to the acknowledgement interval before sending a stand-alone acknowledgement. If there are no unacknowledged messages, the RM Destination can choose not to send an acknowledgement.

More detailed reference information

For more detailed reference information, including descriptions of each element’s sub-elements and attributes, please refer to http://schemas.xmlsoap.org/ws/2005/02/rm/wsrm-policy.xsd.

RMAssertion in rmManager Spring bean

You can configure standard WS-RM policy attributes by adding an RMAssertion within a Apache CXF rmManager Spring bean. This is the best approach if you want to keep all of your WS-RM configuration in the same configuration file; that is, if you want to configure Apache CXF-specific attributes and standard WS-RM policy attributes in the same file.

For example, the configuration in Example 21.5, “Configuring WS-RM Attributes Using an RMAssertion in an rmManager Spring Bean” shows:

  • A standard WS-RM policy attribute, BaseRetransmissionInterval, configured using an RMAssertion within an rmManager Spring bean.
  • An Apache CXF-specific RM attribute, intraMessageThreshold, configured in the same configuration file.

Example 21.5. Configuring WS-RM Attributes Using an RMAssertion in an rmManager Spring Bean

<beans xmlns:wsrm-policy="http://schemas.xmlsoap.org/ws/2005/02/rm/policy"
       xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager"
...>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <wsrm-policy:RMAssertion>
        <wsrm-policy:BaseRetransmissionInterval Milliseconds="4000"/>
    </wsrm-policy:RMAssertion>
    <wsrm-mgr:destinationPolicy>
        <wsrm-mgr:acksPolicy intraMessageThreshold="0" />
    </wsrm-mgr:destinationPolicy>
</wsrm-mgr:rmManager>
</beans>
Policy within a feature

You can configure standard WS-RM policy attributes within features, as shown in Example 21.6, “Configuring WS-RM Attributes as a Policy within a Feature”.

Example 21.6. Configuring WS-RM Attributes as a Policy within a Feature

<xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:wsa="http://cxf.apache.org/ws/addressing"
        xmlns:wsp="http://www.w3.org/2006/07/ws-policy"
        xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"
        xmlns:jaxws="http://cxf.apache.org/jaxws"
        xsi:schemaLocation="
http://www.w3.org/2006/07/ws-policy http://www.w3.org/2006/07/ws-policy.xsd
http://cxf.apache.org/ws/addressing http://cxf.apache.org/schema/ws/addressing.xsd
http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
    <jaxws:endpoint name="{http://cxf.apache.org/greeter_control}GreeterPort" createdFromAPI="true">
        <jaxws:features>
               <wsp:Policy>
                   <wsrm:RMAssertion xmlns:wsrm="http://schemas.xmlsoap.org/ws/2005/02/rm/policy">
                     <wsrm:AcknowledgementInterval Milliseconds="200" />
                   </wsrm:RMAssertion>
                   <wsam:Addressing xmlns:wsam="http://www.w3.org/2007/02/addressing/metadata">
                       <wsp:Policy>
                            <wsam:NonAnonymousResponses/>
                       </wsp:Policy>
                   </wsam:Addressing>
              </wsp:Policy>
        </jaxws:features>
    </jaxws:endpoint>
</beans>
WSDL file

If you use the WS-Policy framework to enable WS-RM, you can configure standard WS-RM policy attributes in a WSDL file. This is a good approach if you want your service to interoperate and use WS-RM seamlessly with consumers deployed to other policy-aware Web services stacks.

For an example, see the section called “WS-Policy framework: implicitly adding interceptors” where the base retransmission interval is configured in the WSDL file.

External attachment

You can configure standard WS-RM policy attributes in an external attachment file. This is a good approach if you cannot, or do not want to, change your WSDL file.

Example 21.7, “Configuring WS-RM in an External Attachment” shows an external attachment that enables both WS-A and WS-RM (base retransmission interval of 30 seconds) for a specific EPR.

Example 21.7. Configuring WS-RM in an External Attachment

<attachments xmlns:wsp="http://www.w3.org/2006/07/ws-policy" xmlns:wsa="http://www.w3.org/2005/08/addressing">
    <wsp:PolicyAttachment>
        <wsp:AppliesTo>
           <wsa:EndpointReference>
                <wsa:Address>http://localhost:9020/SoapContext/GreeterPort</wsa:Address>
            </wsa:EndpointReference>
        </wsp:AppliesTo>
        <wsp:Policy>
            <wsam:Addressing xmlns:wsam="http://www.w3.org/2007/02/addressing/metadata">
                <wsp:Policy/>
            </wsam:Addressing>
            <wsrmp:RMAssertion xmlns:wsrmp="http://schemas.xmlsoap.org/ws/2005/02/rm/policy">
                <wsrmp:BaseRetransmissionInterval Milliseconds="30000"/>
            </wsrmp:RMAssertion>
        </wsp:Policy>
    </wsp:PolicyAttachment>
</attachments>/

21.5.3. WS-RM Configuration Use Cases

Overview

This subsection focuses on configuring WS-RM attributes from a use case point of view. Where an attribute is a standard WS-RM policy attribute, defined in the http://schemas.xmlsoap.org/ws/2005/02/rm/policy/ namespace, only the example of setting it in an RMAssertion within an rmManager Spring bean is shown. For details of how to set such attributes as a policy within a feature; in a WSDL file, or in an external attachment, see Section 21.5.2, “Configuring Standard WS-RM Policy Attributes”.

The following use cases are covered:

Base retransmission interval

The BaseRetransmissionInterval element specifies the interval at which an RM source retransmits a message that has not yet been acknowledged. It is defined in the http://schemas.xmlsoap.org/ws/2005/02/rm/wsrm-policy.xsd schema file. The default value is 3000 milliseconds.

Example 21.8, “Setting the WS-RM Base Retransmission Interval” shows how to set the WS-RM base retransmission interval.

Example 21.8. Setting the WS-RM Base Retransmission Interval

<beans xmlns:wsrm-policy="http://schemas.xmlsoap.org/ws/2005/02/rm/policy
...>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <wsrm-policy:RMAssertion>
        <wsrm-policy:BaseRetransmissionInterval Milliseconds="4000"/>
    </wsrm-policy:RMAssertion>
</wsrm-mgr:rmManager>
</beans>
Exponential backoff for retransmission

The ExponentialBackoff element determines if successive retransmission attempts for an unacknowledged message are performed at exponential intervals.

The presence of the ExponentialBackoff element enables this feature. An exponential backoff ratio of 2 is used by default. ExponentialBackoff is a flag. When the element is present, exponential backoff is enabled. When the element is absent, exponential backoff is disabled. No value is required.

Example 21.9, “Setting the WS-RM Exponential Backoff Property” shows how to set the WS-RM exponential backoff for retransmission.

Example 21.9. Setting the WS-RM Exponential Backoff Property

<beans xmlns:wsrm-policy="http://schemas.xmlsoap.org/ws/2005/02/rm/policy
...>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <wsrm-policy:RMAssertion>
        <wsrm-policy:ExponentialBackoff/>
    </wsrm-policy:RMAssertion>
</wsrm-mgr:rmManager>
</beans>
Acknowledgement interval

The AcknowledgementInterval element specifies the interval at which the WS-RM destination sends asynchronous acknowledgements. These are in addition to the synchronous acknowledgements that it sends on receipt of an incoming message. The default asynchronous acknowledgement interval is 0 milliseconds. This means that if the AcknowledgementInterval is not configured to a specific value, acknowledgements are sent immediately (that is, at the first available opportunity).

Asynchronous acknowledgements are sent by the RM destination only if both of the following conditions are met:

  • The RM destination is using a non-anonymous wsrm:acksTo endpoint.
  • The opportunity to piggyback an acknowledgement on a response message does not occur before the expiry of the acknowledgement interval.

Example 21.10, “Setting the WS-RM Acknowledgement Interval” shows how to set the WS-RM acknowledgement interval.

Example 21.10. Setting the WS-RM Acknowledgement Interval

<beans xmlns:wsrm-policy="http://schemas.xmlsoap.org/ws/2005/02/rm/policy
...>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <wsrm-policy:RMAssertion>
        <wsrm-policy:AcknowledgementInterval Milliseconds="2000"/>
    </wsrm-policy:RMAssertion>
</wsrm-mgr:rmManager>
</beans>
Maximum unacknowledged messages threshold

The maxUnacknowledged attribute sets the maximum number of unacknowledged messages that can accrue per sequence before the sequence is terminated.

Example 21.11, “Setting the WS-RM Maximum Unacknowledged Message Threshold” shows how to set the WS-RM maximum unacknowledged messages threshold.

Example 21.11. Setting the WS-RM Maximum Unacknowledged Message Threshold

<beans xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager
...>
<wsrm-mgr:reliableMessaging>
    <wsrm-mgr:sourcePolicy>
        <wsrm-mgr:sequenceTerminationPolicy maxUnacknowledged="20" />
    </wsrm-mgr:sourcePolicy>
</wsrm-mgr:reliableMessaging>
</beans>
Maximum length of an RM sequence

The maxLength attribute sets the maximum length of a WS-RM sequence. The default value is 0, which means that the length of a WS-RM sequence is unbound.

When this attribute is set, the RM endpoint creates a new RM sequence when the limit is reached, and after receiving all of the acknowledgements for the previously sent messages. The new message is sent using a newsequence.

Example 21.12, “Setting the Maximum Length of a WS-RM Message Sequence” shows how to set the maximum length of an RM sequence.

Example 21.12. Setting the Maximum Length of a WS-RM Message Sequence

<beans xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager
...>
<wsrm-mgr:reliableMessaging>
    <wsrm-mgr:sourcePolicy>
        <wsrm-mgr:sequenceTerminationPolicy maxLength="100" />
    </wsrm-mgr:sourcePolicy>
</wsrm-mgr:reliableMessaging>
</beans>
Message delivery assurance policies

You can configure the RM destination to use the following delivery assurance policies:

  • AtMostOnce — The RM destination delivers the messages to the application destination only once. If a message is delivered more than once an error is raised. It is possible that some messages in a sequence may not be delivered.
  • AtLeastOnce — The RM destination delivers the messages to the application destination at least once. Every message sent will be delivered or an error will be raised. Some messages might be delivered more than once.
  • InOrder — The RM destination delivers the messages to the application destination in the order that they are sent. This delivery assurance can be combined with the AtMostOnce or AtLeastOnce assurances.

Example 21.13, “Setting the WS-RM Message Delivery Assurance Policy” shows how to set the WS-RM message delivery assurance.

Example 21.13. Setting the WS-RM Message Delivery Assurance Policy

<beans xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager
...>
<wsrm-mgr:reliableMessaging>
    <wsrm-mgr:deliveryAssurance>
        <wsrm-mgr:AtLeastOnce />
    </wsrm-mgr:deliveryAssurance>
</wsrm-mgr:reliableMessaging>
</beans>

21.6. Configuring WS-RM Persistence

Overview

The Apache CXF WS-RM features already described in this chapter provide reliability for cases such as network failures. WS-RM persistence provides reliability across other types of failure such as an RM source or an RM destination crash.

WS-RM persistence involves storing the state of the various RM endpoints in persistent storage. This enables the endpoints to continue sending and receiving messages when they are reincarnated.

Apache CXF enables WS-RM persistence in a configuration file. The default WS-RM persistence store is JDBC-based. For convenience, Apache CXF includes Derby for out-of-the-box deployment. In addition, the persistent store is also exposed using a Java API. To implement your own persistence mechanism, you can implement one using this API with your preferred DB.

Important

WS-RM persistence is supported for oneway calls only, and it is disabled by default.

How it works

Apache CXF WS-RM persistence works as follows:

  • At the RM source endpoint, an outgoing message is persisted before transmission. It is evicted from the persistent store after the acknowledgement is received.
  • After a recovery from crash, it recovers the persisted messages and retransmits until all the messages have been acknowledged. At that point, the RM sequence is closed.
  • At the RM destination endpoint, an incoming message is persisted, and upon a successful store, the acknowledgement is sent. When a message is successfully dispatched, it is evicted from the persistent store.
  • After a recovery from a crash, it recovers the persisted messages and dispatches them. It also brings the RM sequence to a state where new messages are accepted, acknowledged, and delivered.

Enabling WS-persistence

To enable WS-RM persistence, you must specify the object implementing the persistent store for WS-RM. You can develop your own or you can use the JDBC based store that comes with Apache CXF.

The configuration shown in Example 21.14, “Configuration for the Default WS-RM Persistence Store” enables the JDBC-based store that comes with Apache CXF.

Example 21.14. Configuration for the Default WS-RM Persistence Store

<bean id="RMTxStore" class="org.apache.cxf.ws.rm.persistence.jdbc.RMTxStore"/>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <property name="store" ref="RMTxStore"/>
</wsrm-mgr:rmManager>

Configuring WS-persistence

The JDBC-based store that comes with Apache CXF supports the properties shown in Table 21.4, “JDBC Store Properties”.

Table 21.4. JDBC Store Properties
Attribute NameTypeDefault Setting

driverClassName

String

org.apache.derby.jdbc.EmbeddedDriver

userName

String

null

passWord

String

null

url

String

jdbc:derby:rmdb;create=true

The configuration shown in Example 21.15, “Configuring the JDBC Store for WS-RM Persistence” enables the JDBC-based store that comes with Apache CXF, while setting the driverClassName and url to non-default values.

Example 21.15. Configuring the JDBC Store for WS-RM Persistence

<bean id="RMTxStore" class="org.apache.cxf.ws.rm.persistence.jdbc.RMTxStore">
    <property name="driverClassName" value="com.acme.jdbc.Driver"/>
    <property name="url" value="jdbc:acme:rmdb;create=true"/>
</bean>

Chapter 22. Enabling High Availability

Abstract

This chapter explains how to enable and configure high availability in the Apache CXF runtime.

22.1. Introduction to High Availability

Overview

Scalable and reliable applications require high availability to avoid any single point of failure in a distributed system. You can protect your system from single points of failure using replicated services.

A replicated service is comprised of multiple instances, or replicas, of the same service. Together these act as a single logical service. Clients invoke requests on the replicated service, and Apache CXF delivers the requests to one of the member replicas. The routing to a replica is transparent to the client.

HA with static failover

Apache CXF supports high availability (HA) with static failover in which replica details are encoded in the service WSDL file. The WSDL file contains multiple ports, and can contain multiple hosts, for the same service. The number of replicas in the cluster remains static as long as the WSDL file remains unchanged. Changing the cluster size involves editing the WSDL file.

22.2. Enabling HA with Static Failover

Overview

To enable HA with static failover, you must do the following:

Encode replica details in your service WSDL file

You must encode the details of the replicas in your cluster in your service WSDL file. Example 22.1, “Enabling HA with Static Failover: WSDL File” shows a WSDL file extract that defines a service cluster of three replicas.

Example 22.1. Enabling HA with Static Failover: WSDL File

<wsdl:service name="ClusteredService">
    <wsdl:port binding="tns:Greeter_SOAPBinding" name="Replica1">
        <soap:address location="http://localhost:9001/SoapContext/Replica1"/>
    </wsdl:port>

    <wsdl:port binding="tns:Greeter_SOAPBinding" name="Replica2">
        <soap:address location="http://localhost:9002/SoapContext/Replica2"/>
    </wsdl:port>

    <wsdl:port binding="tns:Greeter_SOAPBinding" name="Replica3">
        <soap:address location="http://localhost:9003/SoapContext/Replica3"/>
    </wsdl:port>

</wsdl:service>

The WSDL extract shown in Example 22.1, “Enabling HA with Static Failover: WSDL File” can be explained as follows:

Defines a service, ClusterService, which is exposed on three ports:

  1. Replica1
  2. Replica2
  3. Replica3

Defines Replica1 to expose the ClusterService as a SOAP over HTTP endpoint on port 9001.

Defines Replica2 to expose the ClusterService as a SOAP over HTTP endpoint on port 9002.

Defines Replica3 to expose the ClusterService as a SOAP over HTTP endpoint on port 9003.

Add the clustering feature to your client configuration

In your client configuration file, add the clustering feature as shown in Example 22.2, “Enabling HA with Static Failover: Client Configuration”.

Example 22.2. Enabling HA with Static Failover: Client Configuration

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:jaxws="http://cxf.apache.org/jaxws"
       xmlns:clustering="http://cxf.apache.org/clustering"
         xsi:schemaLocation="http://cxf.apache.org/jaxws
         http://cxf.apache.org/schemas/jaxws.xsd
         http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans.xsd">

    <jaxws:client name="{http://apache.org/hello_world_soap_http}Replica1"
                  createdFromAPI="true">
        <jaxws:features>
            <clustering:failover/>
        </jaxws:features>
    </jaxws:client>

    <jaxws:client name="{http://apache.org/hello_world_soap_http}Replica2"
                  createdFromAPI="true">
        <jaxws:features>
            <clustering:failover/>
        </jaxws:features>
    </jaxws:client>

    <jaxws:client name="{http://apache.org/hello_world_soap_http}Replica3"
                  createdFromAPI="true">
        <jaxws:features>
            <clustering:failover/>
        </jaxws:features>
    </jaxws:client>

</beans>

22.3. Configuring HA with Static Failover

Overview

By default, HA with static failover uses a sequential strategy when selecting a replica service if the original service with which a client is communicating becomes unavailable, or fails. The sequential strategy selects a replica service in the same sequential order every time it is used. Selection is determined by Apache CXF’s internal service model and results in a deterministic failover pattern.

Configuring a random strategy

You can configure HA with static failover to use a random strategy instead of the sequential strategy when selecting a replica. The random strategy selects a random replica service each time a service becomes unavailable, or fails. The choice of failover target from the surviving members in a cluster is entirely random.

To configure the random strategy, add the configuration shown in Example 22.3, “Configuring a Random Strategy for Static Failover” to your client configuration file.

Example 22.3. Configuring a Random Strategy for Static Failover

<beans ...>
    <bean id="Random" class="org.apache.cxf.clustering.RandomStrategy"/>

    <jaxws:client name="{http://apache.org/hello_world_soap_http}Replica3"
                  createdFromAPI="true">
        <jaxws:features>
            <clustering:failover>
                <clustering:strategy>
                    <ref bean="Random"/>
                </clustering:strategy>
            </clustering:failover>
        </jaxws:features>
    </jaxws:client>
</beans>

The configuration shown in Example 22.3, “Configuring a Random Strategy for Static Failover” can be explained as follows:

Defines a Random bean and implementation class that implements the random strategy.

Specifies that the random strategy is used when selecting a replica.

Chapter 23. Apache CXF Binding IDs

Table of Binding IDs

Table 23.1. Binding IDs for Message Bindings
BindingID

CORBA

http://cxf.apache.org/bindings/corba

HTTP/REST

http://apache.org/cxf/binding/http

SOAP 1.1

http://schemas.xmlsoap.org/wsdl/soap/http

SOAP 1.1 w/ MTOM

http://schemas.xmlsoap.org/wsdl/soap/http?mtom=true

SOAP 1.2

http://www.w3.org/2003/05/soap/bindings/HTTP/

SOAP 1.2 w/ MTOM

http://www.w3.org/2003/05/soap/bindings/HTTP/?mtom=true

XML

http://cxf.apache.org/bindings/xformat

Appendix A. Using the Maven OSGi Tooling

Abstract

Manually creating a bundle, or a collection of bundles, for a large project can be cumbersome. The Maven bundle plug-in makes the job easier by automating the process and providing a number of shortcuts for specifying the contents of the bundle manifest.

A.1. The Maven Bundle Plug-In

The Red Hat Fuse OSGi tooling uses the Maven bundle plug-in from Apache Felix. The bundle plug-in is based on the bnd tool from Peter Kriens. It automates the construction of OSGi bundle manifests by introspecting the contents of the classes being packaged in the bundle. Using the knowledge of the classes contained in the bundle, the plug-in can calculate the proper values to populate the Import-Packages and the Export-Package properties in the bundle manifest. The plug-in also has default values that are used for other required properties in the bundle manifest.

To use the bundle plug-in, do the following:

  1. Section A.2, “Setting up a Red Hat Fuse OSGi project” the bundle plug-in to your project’s POM file.
  2. Section A.3, “Configuring the Bundle Plug-In” the plug-in to correctly populate your bundle’s manifest.

A.2. Setting up a Red Hat Fuse OSGi project

Overview

A Maven project for building an OSGi bundle can be a simple single level project. It does not require any sub-projects. However, it does require that you do the following:

  1. Add the bundle plug-in to your POM.
  2. Instruct Maven to package the results as an OSGi bundle.
Note

There are several Maven archetypes you can use to set up your project with the appropriate settings.

Directory structure

A project that constructs an OSGi bundle can be a single level project. It only requires that you have a top-level POM file and a src folder. As in all Maven projects, you place all Java source code in the src/java folder, and you place any non-Java resources in the src/resources folder.

Non-Java resources include Spring configuration files, JBI endpoint configuration files, and WSDL contracts.

Note

Red Hat Fuse OSGi projects that use Apache CXF, Apache Camel, or another Spring configured bean also include a beans.xml file located in the src/resources/META-INF/spring folder.

Adding a bundle plug-in

Before you can use the bundle plug-in you must add a dependency on Apache Felix. After you add the dependency, you can add the bundle plug-in to the plug-in portion of the POM.

Example A.1, “Adding an OSGi bundle plug-in to a POM” shows the POM entries required to add the bundle plug-in to your project.

Example A.1. Adding an OSGi bundle plug-in to a POM

...
<dependencies>
  <dependency>
    <groupId>org.apache.felix</groupId>
    <artifactId>org.osgi.core</artifactId>
    <version>1.0.0</version>
  </dependency>
...
</dependencies>
...
<build>
  <plugins>
    <plugin>
      <groupId>org.apache.felix</groupId>
      <artifactId>maven-bundle-plugin</artifactId>
      <configuration>
        <instructions>
          <Bundle-SymbolicName>${pom.artifactId}</Bundle-SymbolicName>
          <Import-Package>*,org.apache.camel.osgi</Import-Package>
          <Private-Package>org.apache.servicemix.examples.camel</Private-Package>
        </instructions>
      </configuration>
    </plugin>
  </plugins>
</build>
...

The entries in Example A.1, “Adding an OSGi bundle plug-in to a POM” do the following:

Adds the dependency on Apache Felix

Adds the bundle plug-in to your project

Configures the plug-in to use the project’s artifact ID as the bundle’s symbolic name

Configures the plug-in to include all Java packages imported by the bundled classes; also imports the org.apache.camel.osgi package

Configures the plug-in to bundle the listed class, but not to include them in the list of exported packages

Note

Edit the configuration to meet the requirements of your project.

For more information on configuring the bundle plug-in, see Section A.3, “Configuring the Bundle Plug-In”.

Activating a bundle plug-in

To have Maven use the bundle plug-in, instruct it to package the results of the project as a bundle. Do this by setting the POM file’s packaging element to bundle.

Useful Maven archetypes

There are several Maven archetypes available to generate a project that is preconfigured to use the bundle plug-in:

Spring OSGi archetype

The Spring OSGi archetype creates a generic project for building an OSGi project using Spring DM, as shown:

org.springframework.osgi/spring-bundle-osgi-archetype/1.1.2

You invoke the archetype using the following command:

mvn archetype:generate -DarchetypeGroupId=org.springframework.osgi -DarchetypeArtifactId=spring-osgi-bundle-archetype -DarchetypeVersion=1.1.2 -DgroupId=groupId -DartifactId=artifactId -Dversion=version

Apache CXF code-first archetype

The Apache CXF code-first archetype creates a project for building a service from Java, as shown:

org.apache.servicemix.tooling/servicemix-osgi-cxf-code-first-archetype/2010.02.0-fuse-02-00

You invoke the archetype using the following command:

mvn archetype:generate -DarchetypeGroupId=org.apache.servicemix.tooling -DarchetypeArtifactId=servicemix-osgi-cxf-code-first-archetype -DarchetypeVersion=2010.02.0-fuse-02-00 -DgroupId=groupId -DartifactId=artifactId -Dversion=version

Apache CXF wsdl-first archetype

The Apache CXF wsdl-first archetype creates a project for creating a service from WSDL, as shown:

org.apache.servicemix.tooling/servicemix-osgi-cxf-wsdl-first-archetype/2010.02.0-fuse-02-00

You invoke the archetype using the following command:

mvn archetype:generate -DarchetypeGroupId=org.apache.servicemix.tooling -DarchetypeArtifactId=servicemix-osgi-cxf-wsdl-first-archetype -DarchetypeVersion=2010.02.0-fuse-02-00 -DgroupId=groupId -DartifactId=artifactId -Dversion=version

Apache Camel archetype

The Apache Camel archetype creates a project for building a route that is deployed into Red Hat Fuse, as shown:

org.apache.servicemix.tooling/servicemix-osgi-camel-archetype/2010.02.0-fuse-02-00

You invoke the archetype using the following command:

mvn archetype:generate -DarchetypeGroupId=org.apache.servicemix.tooling -DarchetypeArtifactId=servicemix-osgi-camel-archetype -DarchetypeVersion=2010.02.0-fuse-02-00 -DgroupId=groupId -DartifactId=artifactId -Dversion=version

A.3. Configuring the Bundle Plug-In

Overview

A bundle plug-in requires very little information to function. All of the required properties use default settings to generate a valid OSGi bundle.

While you can create a valid bundle using just the default values, you will probably want to modify some of the values. You can specify most of the properties inside the plug-in’s instructions element.

Configuration properties

Some of the commonly used configuration properties are:

Setting a bundle’s symbolic name

By default, the bundle plug-in sets the value for the Bundle-SymbolicName property to groupId + "." + artifactId, with the following exceptions:

  • If groupId has only one section (no dots), the first package name with classes is returned.

    For example, if the group Id is commons-logging:commons-logging, the bundle’s symbolic name is org.apache.commons.logging.

  • If artifactId is equal to the last section of groupId, then groupId is used.

    For example, if the POM specifies the group ID and artifact ID as org.apache.maven:maven, the bundle’s symbolic name is org.apache.maven.

  • If artifactId starts with the last section of groupId, that portion is removed.

    For example, if the POM specifies the group ID and artifact ID as org.apache.maven:maven-core, the bundle’s symbolic name is org.apache.maven.core.

To specify your own value for the bundle’s symbolic name, add a Bundle-SymbolicName child in the plug-in’s instructions element, as shown in Example A.2, “Setting a bundle’s symbolic name”.

Example A.2. Setting a bundle’s symbolic name

<plugin>
  <groupId>org.apache.felix</groupId>
  <artifactId>maven-bundle-plugin</artifactId>
  <configuration>
   <instructions>
     <Bundle-SymbolicName>${project.artifactId}</Bundle-SymbolicName>
     ...
    </instructions>
  </configuration>
</plugin>

Setting a bundle’s name

By default, a bundle’s name is set to ${project.name}.

To specify your own value for the bundl