Chapter 1. Getting Started with Red Hat build of Apache Camel for Spring Boot
This guide introduces Red Hat build of Apache Camel for Spring Boot and demonstrates how to get started building an application using Red Hat build of Apache Camel for Spring Boot.
1.1. Red Hat build of Apache Camel for Spring Boot starters Copy linkLink copied to clipboard!
Camel support for Spring Boot provides auto-configuration of the Camel and starters for many Camel components. The opinionated auto-configuration of the Camel context auto-detects Camel routes available in the Spring context and registers the key Camel utilities (such as producer template, consumer template and the type converter) as beans.
For information about using a Maven archtype to generate a Camel for Spring Boot application see Generating a Camel for Spring Boot application using Maven.
To get started, you must add the Camel Spring Boot BOM to your Maven pom.xml file.
The camel-spring-boot-bom is a basic BOM that contains the list of Camel Spring Boot starter JARs.
Next, add the Camel Spring Boot starter to startup the Camel Context.
You must also add the component starters that your Spring Boot application requires. The following example shows how to add the auto-configuration starter to the MQTT5 component.
1.1.1. Spring Boot configuration support Copy linkLink copied to clipboard!
Each starter lists configuration parameters you can configure in the standard application.properties or application.yml files. These parameters have the form of camel.component.[component-name].[parameter]. For example to configure the URL of the MQTT5 broker you can set:
camel.component.paho-mqtt5.broker-url=tcp://localhost:61616
camel.component.paho-mqtt5.broker-url=tcp://localhost:61616
1.1.2. Adding Camel routes Copy linkLink copied to clipboard!
Camel routes are detected in the Spring application context, for example a route annotated with org.springframework.stereotype.Component will be loaded, added to the Camel context and run.
1.1.3. Using Domain Specific Languages Copy linkLink copied to clipboard!
Apache Camel uses a Java Domain Specific Language or DSL for creating Enterprise Integration Patterns or Routes in a variety of domain-specific languages (DSL) as listed below:
- Java DSL: Java based DSL using the fluent builder style.
- XML DSL: XML based DSL in Camel XML files only.
- Yaml DSL for creating routes using YAML format.
1.1.3.1. Advantages of DSLs Copy linkLink copied to clipboard!
The advantages of using a DSL over general-purpose languages are the following:
- Easier to learn and easier to work with. You can see where the main logic begins and ends.
- Safer code. DSL in Apache Camel has the solid building blocks which binds all the steps together.
- Errors are domain-specific. In case of failures, error descriptions are more explicit and explanatory. Simpler code also means less error-prone code.
- DSLs are designed to be platform-independent. In case of code changes, its impact is delegated to lower layers.
1.1.3.2. Comparing different DSLs Copy linkLink copied to clipboard!
Following section describes the differences between the DSLs and different scenarios where you may use these DSLs.
| Java DSL | XML DSL | YAML DSL | |
|---|---|---|---|
| Developer tools |
|
|
|
| Hawtio / Fuse Console | Hawtio retrieves the routes from the runtime as XML and display the routes regardless of which DSL was used to create the routes. | Hawtio retrieves the routes from the runtime as XML and display the routes regardless of which DSL was used to create the routes. | Hawtio retrieves the routes from the runtime as XML and display the routes regardless of which DSL was used to create the routes. |
| Software development model | The DSL adopts a fluent builder API. |
| Harder to write from scratch. A modelling development approach with a graphical editor is possible. |
| Debugging code |
|
|
|
| Integration with dependency injection (DI) frameworks | Easier to integrate with any DI framework. | While it is possible to refer to existing beans from DI frameworks in XML DSL, declaring new beans in XML makes these beans exclusive to Camel itself, and not part of the DI framework (for example, Quarkus or Spring Boot). | While it is possible to refer to existing beans from DI frameworks in YAML DSL, declaring new beans in YAML makes these beans exclusive to Camel itself, and not part of the DI framework (for example, Quarkus or Spring Boot). |
| Team size | More flexible, but harder to read code. Good for small co-located teams that work and support code for a long period. |
|
|
| Team structure | Requires the team to have Java developers for developing Camel integrations. Other team members also required to understand Java in order to read the integration flow. |
|
|
| Developer experience and preference |
| Ideal for new users, as it offers a graphical approach for designing routes. | Ideal for new users, as it offers a graphical approach for designing routes. |
1.2. Spring Boot Copy linkLink copied to clipboard!
Spring Boot automatically configures Camel for you. The opinionated autoconfiguration of the Camel context auto-detects Camel routes available in the Spring context and registers the key Camel utilities (like producer template, consumer template and the type converter) as beans.
Maven users will need to add the following dependency to their pom.xml in order to use this component:
<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-spring-boot</artifactId>
</dependency>
<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-spring-boot</artifactId>
</dependency>
camel-spring-boot jar comes with the spring.factories file, so as soon as you add that dependency into your classpath, Spring Boot will automatically auto-configure Camel for you.
1.2.1. Camel Spring Boot Starter Copy linkLink copied to clipboard!
Apache Camel ships a Spring Boot Starter module that allows you to develop Spring Boot applications using starters.
There is also a sample application available in the examples repository.
To use the starter, add the following to your spring boot pom.xml file:
<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-spring-boot-starter</artifactId>
</dependency>
Then you can just add classes with your Camel routes such as:
Then these routes will be started automatically.
You can customize the Camel application in the application.properties or application.yml file.
1.2.2. Spring Boot Auto-configuration Copy linkLink copied to clipboard!
When using spring-boot with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:
<dependency> <groupId>org.apache.camel.springboot</groupId> <artifactId>camel-spring-boot-starter</artifactId> </dependency>
<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-spring-boot-starter</artifactId>
</dependency>
1.2.3. Auto-configured Camel context Copy linkLink copied to clipboard!
The most important piece of functionality provided by the Camel auto-configuration is the CamelContext instance. Camel auto-configuration creates a SpringCamelContext for you and takes care of the proper initialization and shutdown of that context. The created Camel context is also registered in the Spring application context (under the camelContext bean name), so you can access it like any other Spring bean.
1.2.4. Auto-detecting Camel routes Copy linkLink copied to clipboard!
Camel auto-configuration collects all the RouteBuilder instances from the Spring context and automatically injects them into the provided CamelContext. This means that creating new Camel routes with the Spring Boot starter is as simple as adding the @Component annotated class to your classpath:
Or creating a new route RouteBuilder bean in your @Configuration class:
1.2.5. Camel properties Copy linkLink copied to clipboard!
Spring Boot auto-configuration automatically connects to Spring Boot external configuration (which may contain properties placeholders, OS environment variables or system properties) with the Camel properties support. It basically means that any property defined in application.properties file:
route.from = jms:invoices
route.from = jms:invoices
Or set via system property:
java -Droute.to=jms:processed.invoices -jar mySpringApp.jar
java -Droute.to=jms:processed.invoices -jar mySpringApp.jar
can be used as placeholders in Camel route:
1.2.6. Custom Camel context configuration Copy linkLink copied to clipboard!
If you want to perform some operations on CamelContext bean created by Camel auto-configuration, register CamelContextConfiguration instance in your Spring context:
The method beforeApplicationStart will be called just before the Spring context is started, so the CamelContext instance passed to this callback is fully auto-configured. If you add multiple instances of CamelContextConfiguration into your Spring context, each instance is executed.
For a sample application, see the Metrics example in the camel-spring-boot-examples repository.
1.2.7. Auto-configured consumer and producer templates Copy linkLink copied to clipboard!
Camel auto-configuration provides pre-configured ConsumerTemplate and ProducerTemplate instances. You can simply inject them into your Spring-managed beans:
By default, consumer templates and producer templates come with the endpoint cache sizes set to 1000. You can change these values by modifying the following Spring properties:
camel.springboot.consumer-template-cache-size = 100 camel.springboot.producer-template-cache-size = 200
camel.springboot.consumer-template-cache-size = 100
camel.springboot.producer-template-cache-size = 200
1.2.8. Auto-configured TypeConverter Copy linkLink copied to clipboard!
Camel auto-configuration registers a TypeConverter instance named typeConverter in the Spring context.
1.2.8.1. Spring type conversion API bridge Copy linkLink copied to clipboard!
Spring comes with the powerful type conversion API. The Spring API is similar to the Camel type converter API. As both APIs are so similar, Camel Spring Boot automatically registers a bridge converter (SpringTypeConverter) that delegates to the Spring conversion API. This means that out-of-the-box Camel will treat Spring Converters like Camel ones. With this approach you can use both Camel and Spring converters accessed via Camel TypeConverter API:
Under the hood Camel Spring Boot delegates conversion to the Spring’s ConversionService instances available in the application context. If no ConversionService instance is available, Camel Spring Boot auto-configuration will create one for you.
For a sample application, see the Type converter example in the camel-spring-boot-examples repository.
1.2.9. Keeping the application alive Copy linkLink copied to clipboard!
Camel applications which have this feature enabled launch a new thread on startup for the sole purpose of keeping the application alive by preventing JVM termination. This means that after you start a Camel application with Spring Boot, your application waits for a Ctrl+C signal and does not exit immediately.
The controller thread can be activated using the camel.springboot.main-run-controller to true.
camel.springboot.main-run-controller = true
camel.springboot.main-run-controller = true
Applications using web modules (for example, applications that import the org.springframework.boot:spring-boot-web-starter module), usually don’t need to use this feature because the application is kept alive by the presence of other non-daemon threads.
For a sample application, see the POJO example in the camel-spring-boot-examples repository.
1.2.10. Adding XML routes Copy linkLink copied to clipboard!
By default, you can put Camel XML routes in the classpath under the directory camel, which camel-spring-boot will auto-detect and include. You can configure the directory name or turn this off using the configuration option:
turn off
# turn off
camel.springboot.routes-include-pattern = false
scan only in the com/foo/routes classpath
# scan only in the com/foo/routes classpath
camel.springboot.routes-include-pattern = classpath:com/foo/routes/*.xml
The XML files should be Camel XML routes (not <CamelContext>) such as:
For a sample application, see the XML example in the camel-spring-boot-examples repository.
1.2.11. Testing the JUnit 5 way Copy linkLink copied to clipboard!
For testing, Maven users will need to add the following dependencies to their pom.xml:
To test a Camel Spring Boot application, annotate your test class(es) with @CamelSpringBootTest. This brings Camel’s Spring Test support to your application, so that you can write tests using Spring Boot test conventions.
To get the CamelContext or ProducerTemplate, you can inject them into the class in the normal Spring manner, using @Autowired.
You can also use camel-test-spring-junit5 to configure tests declaratively. This example uses the @MockEndpoints annotation to auto-mock an endpoint:
For a sample application, see the Infinispan example in the camel-spring-boot-examples repository.
1.3. Component Starters Copy linkLink copied to clipboard!
Camel Spring Boot supports the following Camel artifacts as Spring Boot Starters:
The BOM for Red Hat build of Apache Camel for Camel Spring Boot lists both supported and unsupported components. See Component Starters for the latest list of supported components.
| Component | Artifact | Description | Support on IBM Power and IBM Z |
|---|---|---|---|
| camel-amqp-starter | Messaging with AMQP protocol using Apache QPid Client. | Yes | |
| camel-aws2-cw-starter | Sending metrics to AWS CloudWatch using AWS SDK version 2.x. | Yes | |
| camel-aws2-ddb-starter | Store and retrieve data from AWS DynamoDB service using AWS SDK version 2.x. | Yes | |
| camel-aws2-kinesis-starter | Consume and produce records from and to AWS Kinesis Streams using AWS SDK version 2.x. | Yes | |
| camel-aws2-lambda-starter | Manage and invoke AWS Lambda functions using AWS SDK version 2.x. | Yes | |
| camel-aws2-s3-starter | Store and retrieve objects from AWS S3 Storage Service using AWS SDK version 2.x. | Yes | |
| camel-aws2-sns-starter | Send messages to an AWS Simple Notification Topic using AWS SDK version 2.x. | Yes | |
| camel-aws2-sqs-starter | Send and receive messages to/from AWS SQS service using AWS SDK version 2.x. | Yes | |
| camel-aws-secrets-manager-starter | Manage secrets using AWS Secrets Manager. | Yes | |
| camel-azure-key-vault-starter | Manage secrets and keys in Azure Key Vault Service | Yes | |
| camel-azure-servicebus-starter | Send and receive messages to/from Azure Event Bus. | Yes | |
| camel-azure-storage-blob-starter | Store and retrieve blobs from Azure Storage Blob Service using SDK v12. | Yes | |
| camel-azure-storage-queue-starter | The azure-storage-queue component is used for storing and retrieving the messages to/from Azure Storage Queue using Azure SDK v12. | Yes | |
| camel-bean-starter | Invoke methods of Java beans stored in Camel registry. | Yes | |
| camel-bean-validator-starter | Validate the message body using the Java Bean Validation API. | Yes | |
| camel-browse-starter | Inspect the messages received on endpoints supporting BrowsableEndpoint. | Yes | |
| camel-cassandraql-starter | Integrate with Cassandra 2.0 using the CQL3 API (not the Thrift API). Based on Cassandra Java Driver provided by DataStax. | Yes | |
| camel-cics-starter | Interact with CICS® general-purpose transaction processing subsystem. | No | |
| camel-controlbus-starter | Manage and monitor Camel routes. | Yes | |
| camel-cron-starter | A generic interface for triggering events at times specified through the Unix cron syntax. | Yes | |
| camel-crypto-starter | Sign and verify exchanges using the Signature Service of the Java Cryptographic Extension (JCE). | Yes | |
| camel-cxf-soap-starter | Expose SOAP WebServices using Apache CXF or connect to external WebServices using CXF WS client. | Yes | |
| camel-cxf-rest-starter | Expose JAX-RS REST services using Apache CXF or connect to external REST services using CXF REST client. | Yes | |
| camel-dataformat-starter | Use a Camel Data Format as a regular Camel Component. | Yes | |
| camel-dataset-starter | Provide data for load and soak testing of your Camel application. | Yes | |
| camel-direct-starter | Call another endpoint from the same Camel Context synchronously. | Yes | |
| camel-elasticsearch-starter | Send requests to ElasticSearch via Java Client API. | Yes | |
| camel-fhir-starter | Exchange information in the healthcare domain using the FHIR (Fast Healthcare Interoperability Resources) standard. | No | |
| camel-file-starter | Read and write files. | Yes | |
| camel-flink-starter | Send DataSet jobs to an Apache Flink cluster. | Yes | |
| camel-ftp-starter | Upload and download files to/from FTP servers. | Yes | |
| camel-google-bigquery-starter | Google BigQuery data warehouse for analytics. | Yes | |
| camel-google-pubsub-starter | Send and receive messages to/from Google Cloud Platform PubSub Service. | Yes | |
| camel-google-secret-manager-starter | Manage Google Secret Manager Secrets | Yes | |
| camel-grpc-starter | Expose gRPC endpoints and access external gRPC endpoints. | Yes | |
| camel-hashicorp-starter | Manage secrets in Hashicorp Vault Service. | Yes | |
| camel-http-starter | Send requests to external HTTP servers using Apache HTTP Client 4.x. | Yes | |
| camel-infinispan-starter | Read and write from/to Infinispan distributed key/value store and data grid. | No | |
| camel-infinispan-embedded-starter | Read and write from/to Infinispan distributed key/value store and data grid. | Yes | |
| camel-jdbc-starter | Access databases through SQL and JDBC. | Yes | |
| camel-jira-starter | Interact with JIRA issue tracker. | Yes | |
| camel-jms-starter | Sent and receive messages to/from a JMS Queue or Topic. | Yes | |
| camel-jolokia-starter | integrates the Jolokia agent configuration in Spring Boot. | Yes | |
| camel-jpa-starter | Store and retrieve Java objects from databases using Java Persistence API (JPA). | Yes | |
| camel-jslt-starter | Query or transform JSON payloads using an JSLT. | Yes | |
| camel-kafka-starter | Sent and receive messages to/from an Apache Kafka broker. | Yes | |
| camel-kamelet-starter | To call Kamelets | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes ConfigMaps and get notified on ConfigMaps changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Custom Resources and get notified on Deployment changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Deployments and get notified on Deployment changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Events and get notified on Events changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Horizontal Pod Autoscalers (HPA) and get notified on HPA changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Jobs. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Namespaces and get notified on Namespace changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Nodes and get notified on Node changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Persistent Volumes and get notified on Persistent Volume changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Persistent Volumes Claims and get notified on Persistent Volumes Claim changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Pods and get notified on Pod changes. | Yes | |
| camel-kubernetes-starter | Yes Perform operations on Kubernetes Replication Controllers and get notified on Replication Controllers changes. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Resources Quotas. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Secrets. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Service Accounts. | Yes | |
| camel-kubernetes-starter | Perform operations on Kubernetes Services and get notified on Service changes. | Yes | |
| camel-kudu-starter | Interact with Apache Kudu, a free and open source column-oriented data store of the Apache Hadoop ecosystem. | No | |
| camel-language-starter | Execute scripts in any of the languages supported by Camel. | Yes | |
| camel-ldap-starter | Perform searches on LDAP servers. | Yes | |
| camel-log-starter | Log messages to the underlying logging mechanism. | Yes | |
| camel-lra-starter | Camel saga binding for Long-Running-Action framework. | Yes | |
| camel-mail-starter | Send and receive emails using imap, pop3 and smtp protocols. | Yes | |
| camel-mail-microsoft-oauth-starter | Camel Mail OAuth2 Authenticator for Microsoft Exchange Online. | Yes | |
| camel-mapstruct-starter | Type Conversion using Mapstruct. | Yes | |
| camel-master-starter | Have only a single consumer in a cluster consuming from a given endpoint; with automatic failover if the JVM dies. | Yes | |
| camel-micrometer-starter | Collect various metrics directly from Camel routes using the Micrometer library. | Yes | |
| camel-minio-starter | Store and retrieve objects from Minio Storage Service using Minio SDK. | Yes | |
| camel-mllp-starter | Communicate with external systems using the MLLP protocol. | Yes | |
| camel-mock-starter | Test routes and mediation rules using mocks. | Yes | |
| camel-mongodb-starter | Perform operations on MongoDB documents and collections. | Yes | |
| camel-mybatis-starter | Performs a query, poll, insert, update or delete in a relational database using MyBatis. | Yes | |
| camel-netty-starter | Socket level networking using TCP or UDP with Netty 4.x. | Yes | |
| camel-olingo4-starter | Communicate with OData 4.0 services using Apache Olingo OData API. | Yes | |
| camel-opensearch-starter | Send requests to OpenSearch via Java Client API. | Yes | |
| camel-kubernetes-starter | Perform operations on OpenShift Builds. | Yes | |
| camel-kubernetes-starter | Perform operations on Openshift Deployment Configs and get notified on Deployment Config changes. | Yes | |
| camel-netty-http-starter | Netty HTTP server and client using the Netty 4.x. | Yes | |
| camel-paho-starter | Communicate with MQTT message brokers using Eclipse Paho MQTT Client. | Yes | |
| camel-paho-mqtt5-starter | Communicate with MQTT message brokers using Eclipse Paho MQTT v5 Client. | Yes | |
| camel-platform-http-starter | Expose HTTP endpoints using the HTTP server available in the current platform. | Yes | |
| camel-quartz-starter | Schedule sending of messages using the Quartz 2.x scheduler. | Yes | |
| camel-ref-starter | Route messages to an endpoint looked up dynamically by name in the Camel Registry. | Yes | |
| camel-rest-starter | Expose REST services or call external REST services. | Yes | |
| camel-saga-starter | Execute custom actions within a route using the Saga EIP. | Yes | |
| camel-salesforce-starter | Communicate with Salesforce using Java DTOs. | Yes | |
| camel-sap-starter | Uses the SAP Java Connector (SAP JCo) library to facilitate bidirectional communication with SAP and the SAP IDoc library to facilitate the transmission of documents in the Intermediate Document (IDoc) format. | Yes | |
| camel-scheduler-starter | Generate messages in specified intervals using java.util.concurrent.ScheduledExecutorService. | Yes | |
| camel-seda-starter | Asynchronously call another endpoint from any Camel Context in the same JVM. | Yes | |
| camel-servlet-starter | Serve HTTP requests by a Servlet. | Yes | |
| camel-slack-starter | Send and receive messages to/from Slack. | Yes | |
| camel-smb-starter | Receive files from SMB (Server Message Block) shares. | Yes | |
| camel-snmp-starter | Receive traps and poll SNMP (Simple Network Management Protocol) capable devices. | Yes | |
| camel-splunk-starter | Publish or search for events in Splunk. | No | |
| camel-spring-batch-starter | Send messages to Spring Batch for further processing. | Yes | |
| camel-spring-jdbc-starter | Access databases through SQL and JDBC with Spring Transaction support. | Yes | |
| camel-spring-ldap-starter | Perform searches in LDAP servers using filters as the message payload. | Yes | |
| camel-spring-rabbitmq-starter | Send and receive messages from RabbitMQ using Spring RabbitMQ client. | Yes | |
| camel-spring-redis-starter | Send and receive messages from Redis. | Yes | |
| camel-spring-ws-starter | You can use this component to integrate with Spring Web Services. It offers client-side support for accessing web services and server-side support for creating your contract-first web services. | Yes | |
| camel-sql-starter | Perform SQL queries using Spring JDBC. | Yes | |
| camel-sql-starter | Perform SQL queries as a JDBC Stored Procedures using Spring JDBC. | Yes | |
| camel-ssh-starter | Execute commands on remote hosts using SSH. | Yes | |
| camel-stub-starter | Stub out any physical endpoints while in development or testing. | Yes | |
| camel-telegram-starter | Send and receive messages acting as a Telegram Bot Telegram Bot API. | Yes | |
| camel-timer-starter | Generate messages in specified intervals using java.util.Timer. | Yes | |
| camel-validator-starter | Validate the payload using XML Schema and JAXP Validation. | Yes | |
| camel-velocity-starter | Transform messages using a Velocity template. | Yes | |
| camel-vertx-http-starter | Send requests to external HTTP servers using Vert.x. | Yes | |
| camel-vertx-websocket-starter | Expose WebSocket endpoints and connect to remote WebSocket servers using Vert.x. | Yes | |
| camel-webhook-starter | Expose webhook endpoints to receive push notifications for other Camel components. | Yes | |
| camel-xj-starter | Transform JSON and XML message using a XSLT. | Yes | |
| camel-xslt-starter | Transforms XML payload using an XSLT template. | Yes | |
| camel-xslt-saxon-starter | Transform XML payloads using an XSLT template using Saxon. | Yes |
| Component | Artifact | Description | Support on IBM Power and IBM Z |
|---|---|---|---|
| camel-avro-starter | Serialize and deserialize messages using Apache Avro binary data format. | Yes | |
| camel-jackson-avro-starter | Marshal POJOs to Avro and back using Jackson. | Yes | |
| camel-bindy-starter | Marshal and unmarshal between POJOs and key-value pair (KVP) format using Camel Bindy. | Yes | |
| camel-beanio-starter | Marshal and unmarshal Java beans to and from flat files (such as CSV, delimited, or fixed length formats). | Yes | |
| camel-hl7-starter | Marshal and unmarshal HL7 (Health Care) model objects using the HL7 MLLP codec. | Yes | |
| camel-jacksonxml-starter | Unmarshal a XML payloads to POJOs and back using XMLMapper extension of Jackson. | Yes | |
| camel-jaxb-starter | Unmarshal XML payloads to POJOs and back using JAXB2 XML marshalling standard. | Yes | |
| camel-gson-starter | Marshal POJOs to JSON and back using Gson | Yes | |
| camel-jackson-starter | Marshal POJOs to JSON and back using Jackson | Yes | |
| camel-jackson-protobuf-starter | Marshal POJOs to Protobuf and back using Jackson. | Yes | |
| camel-soap-starter | Marshal Java objects to SOAP messages and back. | Yes | |
| camel-zipfile-starter | Compression and decompress streams using java.util.zip.ZipStream. | Yes |
| Language | Artifact | Description | Support on IBM Power and IBM Z |
|---|---|---|---|
| camel-core-starter | A fixed value set only once during the route startup. | Yes | |
| camel-core-starter | Evaluate a compiled simple expression. | Yes | |
| camel-core-starter | Gets a property from the Exchange. | Yes | |
| camel-core-starter | File related capabilities for the Simple language. | Yes | |
| camel-groovy-starter | Evaluates a Groovy script. | Yes | |
| camel-core-starter | Gets a header from the Exchange. | Yes | |
| camel-jq-starter | Evaluates a JQ expression against a JSON message body. | Yes | |
| camel-jsonpath-starter | Evaluates a JSONPath expression against a JSON message body. | Yes | |
| camel-core-starter | Uses an existing expression from the registry. | Yes | |
| camel-core-starter | Evaluates a Camel simple expression. | Yes | |
| camel-core-starter | Tokenize text payloads using delimiter patterns. | Yes | |
| camel-xml-jaxp-starter | Tokenize XML payloads. | Yes | |
| camel-xpath-starter | Evaluates an XPath expression against an XML payload. | Yes | |
| camel-saxon-starter | Query and/or transform XML payloads using XQuery and Saxon. | Yes |
| Extensions | Artifact | Description | Support on IBM Power and IBM Z |
|---|---|---|---|
| camel-jasypt-starter | Security using Jasypt | Yes | |
| camel-kamelet-main-starter | Main to run Kamelet standalone | Yes | |
| camel-openapi-java-starter | Rest-dsl support for using openapi doc | Yes | |
| camel-opentelemetry-starter | Distributed tracing using OpenTelemetry | Yes | |
| camel-spring-security-starter | Security using Spring Security | Yes | |
| camel-yaml-dsl-starter | Camel DSL with YAML | Yes |
1.4. Starter Configuration Copy linkLink copied to clipboard!
Clear and accessible configuration is a crucial part of any application. Camel starters fully support Spring Boot’s external configuration mechanism. You can also configure them through Spring Beans for more complex use cases.
1.4.1. Using External Configuration Copy linkLink copied to clipboard!
Internally, every starter is configured through Spring Boot’s ConfigurationProperties. Each configuration parameter can be set in various ways (application.[properties|json|yaml] files, command line arguments, environments variables etc.). Parameters have the form of camel.[component|language|dataformat].[name].[parameter]
For example to configure the URL of the MQTT5 broker you can set:
camel.component.paho-mqtt5.broker-url=tcp://localhost:61616
camel.component.paho-mqtt5.broker-url=tcp://localhost:61616
Or to configure the delimeter of the CSV dataformat to be a semicolon(;) you can set:
camel.dataformat.csv.delimiter=;
camel.dataformat.csv.delimiter=;
Camel will use the Type Converter mechanism when setting properties to the desired type.
You can refer to beans in the Registry using the #bean:name:
camel.component.jms.transactionManager=#bean:myjtaTransactionManager
camel.component.jms.transactionManager=#bean:myjtaTransactionManager
The Bean would be typically created in Java:
Beans can also be created in configuration files but this is not recommended for complex use cases.
1.4.2. Using Beans Copy linkLink copied to clipboard!
Starters can also be created and configured via Spring Beans. Before creating a starter , Camel will first lookup it up in the Registry by it’s name if it already exists. For example to configure a Kafka component:
The Bean name has to be equal to that of the Component, Dataformat or Language that you are configuring. If the Bean name isn’t specified in the annotation it will be set to the method name.
Typical Camel Spring Boot projects will use a combination of external configuration and Beans to configure an application. For more examples on how to configure your Camel Spring Boot project, see the examples repository.
1.5. Generating a Camel for Spring Boot application using Maven Copy linkLink copied to clipboard!
You can generate a Red Hat build of Apache Camel for Spring Boot application using the Maven archetype org.apache.camel.archetypes:camel-archetype-spring-boot:4.8.5.redhat-00008.
Procedure
Run the following command:
Copy to Clipboard Copied! Toggle word wrap Toggle overflow Build the application:
mvn package -f csb-app/pom.xml
mvn package -f csb-app/pom.xmlCopy to Clipboard Copied! Toggle word wrap Toggle overflow Run the application:
java -jar csb-app/target/csb-app-1.0-SNAPSHOT.jar
java -jar csb-app/target/csb-app-1.0-SNAPSHOT.jarCopy to Clipboard Copied! Toggle word wrap Toggle overflow Verify that the application is running by examining the console log for the Hello World output which is generated by the application.
com.redhat.MySpringBootApplication : Started MySpringBootApplication in 3.514 seconds (JVM running for 4.006) Hello World Hello World
com.redhat.MySpringBootApplication : Started MySpringBootApplication in 3.514 seconds (JVM running for 4.006) Hello World Hello WorldCopy to Clipboard Copied! Toggle word wrap Toggle overflow
1.6. Deploying a Camel Spring Boot application to OpenShift Copy linkLink copied to clipboard!
This guide demonstrates how to deploy a Camel Spring Boot application to OpenShift.
Prerequisites
- You have access to the OpenShift cluster.
-
The OpenShift
ocCLI client is installed or you have access to the OpenShift Container Platform web console.
The certified OpenShift Container platforms are listed in the Camel for Spring Boot Supported Configurations. The Red Hat OpenJDK 11 (ubi8/openjdk-11) container image is used in the following example.
Procedure
- Generate a Camel for Spring Boot application using Maven by following the instructions in section 1.5 Generating a Camel for Spring Boot application using Maven of this guide.
Under the directory which the modified pom.xml exists, execute the following command.
mvn clean -DskipTests oc:deploy -Popenshift
mvn clean -DskipTests oc:deploy -PopenshiftCopy to Clipboard Copied! Toggle word wrap Toggle overflow Verify that the CSB application is running on the pod.
oc logs -f dc/csb-app
oc logs -f dc/csb-appCopy to Clipboard Copied! Toggle word wrap Toggle overflow
1.7. Applying patch to Red Hat build of Apache Camel for Spring Boot Copy linkLink copied to clipboard!
Using the new patch-maven-plugin mechanism, you can apply a patch to your Red Hat Red Hat build of Apache Camel for Spring Boot application. This mechanism allows you to change the individual versions provided by different Red Hat application BOMS, for example, camel-spring-boot-bom.
The purpose of the patch-maven-plugin is to update the versions of the dependencies listed in the Camel on Spring Boot BOM to the versions specified in the patch metadata that you wish to apply to your applications.
The patch-maven-plugin performs the following operations:
- Retrieve the patch metadata related to current Red Hat application BOMs.
- Apply the version changes to <dependencyManagement> imported from the BOMs.
After the patch-maven-plugin fetches the metadata, it iterates through all managed and direct dependencies of the project where the plugin was declared and replaces the dependency versions (if they match) using CVE/patch metadata. After the versions are replaced, the Maven build continues and progresses through standard Maven project stages.
Procedure
The following procedure explains how to apply the patch to your application.
Add
patch-maven-pluginto your project’spom.xmlfile. The version of thepatch-maven-pluginmust be the same as the version of the Camel on Spring Boot BOM.Copy to Clipboard Copied! Toggle word wrap Toggle overflow When you run any of the
mvn clean deploy,mvn validate, ormvn dependency:treecommands, the plugin searches through the project modules to check if the modules use the Red Hat Red Hat build of Apache Camel for Spring Boot BOM. Only the following is the supported BOM:-
com.redhat.camel.springboot.platform:camel-spring-boot-bom: for Red Hat build of Apache Camel for Spring Boot BOM
-
If the plugin does not find the above BOM, the plugin displays the following messages:
Copy to Clipboard Copied! Toggle word wrap Toggle overflow If the correct BOM is used, the patch metadata is found, but without any patches.
Copy to Clipboard Copied! Toggle word wrap Toggle overflow The
patch-maven-pluginattempts to fetch this Maven metadata.For the projects with Camel Spring Boot BOM, the
com.redhat.camel.springboot.platform:redhat-camel-spring-boot-patch-metadata/maven-metadata.xmlis resolved. This XML data is the metadata for the artifact with thecom.redhat.camel.springboot.platform:redhat-camel-spring-boot-patch-metadata:RELEASEcoordinates.Example metadata generated by Maven
Copy to Clipboard Copied! Toggle word wrap Toggle overflow
-
The
patch-maven-pluginparses the metadata to select the version which applies to the current project. This action is possible only for the Maven projects using Camel on Spring Boot BOM with the specific version. Only the metadata that matches the version range or later is applicable, and it fetches only the latest version of the metadata. The
patch-maven-plugincollects a list of remote Maven repositories for downloading the patch metadata identified bygroupId,artifactId, andversionfound in previous steps. These Maven repositories are listed in the project’s<repositories>elements in the active profiles, and also the repositories from thesettings.xmlfile.Copy to Clipboard Copied! Toggle word wrap Toggle overflow Whether the metadata comes from a remote repository, local repository, or ZIP file, it is analyzed by the
patch-maven-plugin. The fetched metadata contains a list of CVEs, and for each CVE, we have a list of the affected Maven artifacts (specified by glob patterns and version ranges) together with a version that contains a fix for a given CVE. For example,Copy to Clipboard Copied! Toggle word wrap Toggle overflow Finally a list of fixes specified in patch metadata is consulted when iterating over all managed dependencies in the current project. These dependencies (and managed dependencies) that match are changed to fixed versions. For example:
Copy to Clipboard Copied! Toggle word wrap Toggle overflow
Skipping the patch
If you do not wish to apply a specific patch to your project, the patch-maven-plugin provides a skip option. Assuming that you have already added the patch-maven-plugin to the project’s pom.xml file, and you do not wish to alter the versions, you can use one of the following method to skip the patch.
-
Add the skip option to your project’s
pom.xmlfile as follows.
-
Or use the
-DskipPatchoption when running themvncommand as follows.
As shown in the above output, the patch-maven-plugin was not invoked, which resulted in the patch not being applied to the application.
1.8. Camel REST DSL OpenApi Maven Plugin Copy linkLink copied to clipboard!
The Camel REST DSL OpenApi Maven Plugin supports the following goals.
- camel-restdsl-openapi:generate - To generate consumer REST DSL RouteBuilder source code from OpenApi specification
- camel-restdsl-openapi:generate-with-dto - To generate consumer REST DSL RouteBuilder source code from OpenApi specification and with DTO model classes generated via the swagger-codegen-maven-plugin.
- camel-restdsl-openapi:generate-xml - To generate consumer REST DSL XML source code from OpenApi specification
- camel-restdsl-openapi:generate-xml-with-dto - To generate consumer REST DSL XML source code from OpenApi specification and with DTO model classes generated via the swagger-codegen-maven-plugin.
- camel-restdsl-openapi:generate-yaml - To generate consumer REST DSL YAML source code from OpenApi specification
- camel-restdsl-openapi:generate-yaml-with-dto - To generate consumer REST DSL YAML source code from OpenApi specification and with DTO model classes generated via the swagger-codegen-maven-plugin.
1.8.1. Adding plugin to Maven pom.xml Copy linkLink copied to clipboard!
This plugin can be added to your Maven pom.xml file by adding it to the plugins section, for example in a Spring Boot application:
The plugin can then be executed using its prefix camel-restdsl-openapi as shown below.
$mvn camel-restdsl-openapi:generate
$mvn camel-restdsl-openapi:generate
1.8.2. camel-restdsl-openapi:generate Copy linkLink copied to clipboard!
The goal of the Camel REST DSL OpenApi Maven Plugin is used to generate REST DSL RouteBuilder implementation source code from Maven.
1.8.2.1. Options Copy linkLink copied to clipboard!
The plugin supports the following options which can be configured from the command line (use -D syntax), or defined in the pom.xml file in the configuration tag.
| Parameter | Default Value | Description |
|---|---|---|
|
|
|
Set to |
|
|
Used for including only the operation ids specified. Multiple ids can be separated by comma. Wildcards can be used, eg | |
|
|
|
URI of the OpenApi specification, supports filesystem paths, HTTP and classpath resources, by default |
|
| Adds authorization headers when fetching the OpenApi specification definitions remotely. Pass in a URL-encoded string of name:header with a comma separating multiple values. | |
|
|
from |
Name of the generated class, taken from the OpenApi specification title or set to |
|
|
from |
Name of the package for the generated class, taken from the OpenApi specification host value or |
|
|
|
Which indenting character(s) to use, by default four spaces, you can use |
|
|
|
Where to place the generated source file, by default |
|
|
Fully qualified class name of the class that implements | |
|
|
| The default to syntax for the to uri, which is to use the direct component. |
|
|
| Whether to include generation of the rest configuration with detected rest component to be used. |
|
|
Define openapi endpoint path if | |
|
|
| Whether to enable request validation. |
|
| Overrides the api base path as defined in the OpenAPI specification. | |
|
|
| Allows generation of custom RequestMapping mapping values. Multiple mapping values can be passed as:
|
1.8.3. Spring Boot Project with Servlet component Copy linkLink copied to clipboard!
If the Maven project is a Spring Boot project and restConfiguration is enabled and the servlet component is being used as REST component, then this plugin will autodetect the package name (if packageName has not been explicitly configured) where the @SpringBootApplication main class is located, and use the same package name for generating Rest DSL source code and a needed CamelRestController support class.
1.8.4. camel-restdsl-openapi:generate-with-dto Copy linkLink copied to clipboard!
Works as generate goal but also generates DTO model classes by automatic executing the swagger-codegen-maven-plugin to generate java source code of the DTO model classes from the OpenApi specification.
This plugin has been scoped and limited to only support a good effort set of defaults for using the swagger-codegen-maven-plugin to generate the model DTOs. If you need more power and flexibility then use the Swagger Codegen Maven Plugin directly to generate the DTO and not this plugin.
The DTO classes may require additional dependencies such as:
1.8.4.1. Options Copy linkLink copied to clipboard!
The plugin supports the following additional options
| Parameter | Default Value | Description |
|---|---|---|
|
| 3.0.36 |
The version of the |
|
| Target output path (default is ${project.build.directory}/generated-sources/openapi) | |
|
|
| The package to use for generated model objects/classes |
|
| Sets the pre- or suffix for model classes and enums | |
|
| Sets the pre- or suffix for model classes and enums | |
|
| false | Enable XML annotations inside the generated models (only works with libraries that provide support for JSON and XML) |
|
|
Pass a map of language-specific parameters to |
1.8.5. camel-restdsl-openapi:generate-xml Copy linkLink copied to clipboard!
The camel-restdsl-openapi:generate-xml goal of the Camel REST DSL OpenApi Maven Plugin is used to generate REST DSL XML implementation source code from Maven.
1.8.5.1. Options Copy linkLink copied to clipboard!
The plugin supports the following options which can be configured from the command line (use -D syntax), or defined in the pom.xml file in the <configuration> tag.
| Parameter | Default Value | Description |
|---|---|---|
|
|
|
Set to |
|
|
Used for including only the operation ids specified. Multiple ids can be separated by comma. Wildcards can be used, eg | |
|
|
|
URI of the OpenApi specification, supports filesystem paths, HTTP and classpath resources, by default |
|
| Adds authorization headers when fetching the OpenApi specification definitions remotely. Pass in a URL-encoded string of name:header with a comma separating multiple values. | |
|
|
|
Where to place the generated source file, by default |
|
|
| The name of the XML file as output. |
|
|
| If enabled generates OSGi Blueprint XML instead of Spring XML. |
|
|
Fully qualified class name of the class that implements | |
|
|
| The default to syntax for the to uri, which is to use the direct component. |
|
|
| |
| Whether to include generation of the rest configuration with detected rest component to be used. |
| |
|
Define openapi endpoint path if |
|
|
| Whether to enable request validation. |
| |
| Overrides the api base path as defined in the OpenAPI specification. |
|
|
1.8.6. camel-restdsl-openapi:generate-xml-with-dto Copy linkLink copied to clipboard!
Works as generate-xml goal but also generates DTO model classes by automatic executing the swagger-codegen-maven-plugin to generate java source code of the DTO model classes from the OpenApi specification.
This plugin has been scoped and limited to only support a good effort set of defaults for using the swagger-codegen-maven-plugin to generate the model DTOs. If you need more power and flexibility then use the Swagger Codegen Maven Plugin directly to generate the DTO and not this plugin.
The DTO classes may require additional dependencies such as:
1.8.6.1. Options Copy linkLink copied to clipboard!
The plugin supports the following additional options
| Parameter | Default Value | Description |
|---|---|---|
|
| 3.0.36 |
The version of the |
|
| Target output path (default is ${project.build.directory}/generated-sources/openapi) | |
|
|
| The package to use for generated model objects/classes |
|
| Sets the pre- or suffix for model classes and enums | |
|
| Sets the pre- or suffix for model classes and enums | |
|
| false | Enable XML annotations inside the generated models (only works with libraries that provide support for JSON and XML) |
|
|
Pass a map of language-specific parameters to |
1.8.7. camel-restdsl-openapi:generate-yaml Copy linkLink copied to clipboard!
The camel-restdsl-openapi:generate-yaml goal of the Camel REST DSL OpenApi Maven Plugin is used to generate REST DSL YAML implementation source code from Maven.
1.8.7.1. Options Copy linkLink copied to clipboard!
The plugin supports the following options which can be configured from the command line (use -D syntax), or defined in the pom.xml file in the <configuration> tag.
| Parameter | Default Value | Description |
|---|---|---|
|
|
|
Set to |
|
|
Used for including only the operation ids specified. Multiple ids can be separated by comma. Wildcards can be used, eg | |
|
|
|
URI of the OpenApi specification, supports filesystem paths, HTTP and classpath resources, by default |
|
| Adds authorization headers when fetching the OpenApi specification definitions remotely. Pass in a URL-encoded string of name:header with a comma separating multiple values. | |
|
|
|
Where to place the generated source file, by default |
|
|
| The name of the XML file as output. |
|
|
Fully qualified class name of the class that implements | |
|
|
| The default to syntax for the to uri, which is to use the direct component. |
|
|
| |
| Whether to include generation of the rest configuration with detected rest component to be used. |
| |
|
Define openapi endpoint path if |
|
|
| Whether to enable request validation. |
| |
| Overrides the api base path as defined in the OpenAPI specification. |
|
|
1.8.8. camel-restdsl-openapi:generate-yaml-with-dto Copy linkLink copied to clipboard!
Works as generate-yaml goal but also generates DTO model classes by automatic executing the swagger-codegen-maven-plugin to generate java source code of the DTO model classes from the OpenApi specification.
This plugin has been scoped and limited to only support a good effort set of defaults for using the swagger-codegen-maven-plugin to generate the model DTOs. If you need more power and flexibility then use the Swagger Codegen Maven Plugin directly to generate the DTO and not this plugin.
The DTO classes may require additional dependencies such as:
1.8.8.1. Options Copy linkLink copied to clipboard!
The plugin supports the following additional options
| Parameter | Default Value | Description |
|---|---|---|
|
| 3.0.36 |
The version of the |
|
| Target output path (default is ${project.build.directory}/generated-sources/openapi) | |
|
|
| The package to use for generated model objects/classes |
|
| Sets the pre- or suffix for model classes and enums | |
|
| Sets the pre- or suffix for model classes and enums | |
|
| false | Enable XML annotations inside the generated models (only works with libraries that provide support for JSON and XML) |
|
|
Pass a map of language-specific parameters to |
1.9. Support for FIPS Compliance Copy linkLink copied to clipboard!
You can install an OpenShift Container Platform cluster that uses FIPS Validated / Modules in Process cryptographic libraries on the x86_64 architecture.
For the Red Hat Enterprise Linux CoreOS (RHCOS) machines in your cluster, this change applies when the machines deploy based on the status of an option in the install-config.yaml file, which governs the cluster options that users can change during cluster deployment. With Red Hat Enterprise Linux (RHEL) machines, you must enable FIPS mode when installing the operating system on the machines you plan to use as worker machines. These configuration methods ensure that your cluster meets the requirements of a FIPS compliance audit. Only FIPS Validated / Modules in Process cryptography packages are enabled before the initial system boot.
Because you must enable FIPS before your cluster’s operating system boots for the first time, you cannot enable FIPS after you deploy a cluster.
1.9.1. FIPS validation in OpenShift Container Platform Copy linkLink copied to clipboard!
OpenShift Container Platform uses certain FIPS Validated / Modules in Process modules within RHEL and RHCOS for its operating system components. For example, when users SSH into OpenShift Container Platform clusters and containers, those connections are properly encrypted.
OpenShift Container Platform components are written in Go and built with Red Hat’s Golang compiler. When you enable FIPS mode for your cluster, all OpenShift Container Platform components that require cryptographic signing call RHEL and RHCOS cryptographic libraries.
For more details about FIPS, see FIPS mode attributes and limitations
For details on deploying Camel Spring Boot on OpenShift, see How to deploy a Camel Spring Boot application to OpenShift?
Details about supported configurations can be found at, Camel for Spring Boot Supported Configurations