Chapter 66. CoAP Component
Available as of Camel version 2.16
Camel-CoAP is an Apache Camel component that allows you to work with CoAP, a lightweight REST-type protocol for machine-to-machine operation. CoAP, Constrained Application Protocol is a specialized web transfer protocol for use with constrained nodes and constrained networks and it is based on RFC 7252.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-coap</artifactId> <version>x.x.x</version> <!-- use the same version as your Camel core version --> </dependency>
66.1. Options
The CoAP component has no options.
The CoAP endpoint is configured using URI syntax:
coap:uri
with the following path and query parameters:
66.1.1. Path Parameters (1 parameters):
| Name | Description | Default | Type |
|---|---|---|---|
| uri | The URI for the CoAP endpoint | URI |
66.1.2. Query Parameters (5 parameters):
| Name | Description | Default | Type |
|---|---|---|---|
| bridgeErrorHandler (consumer) | Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored. | false | boolean |
| coapMethodRestrict (consumer) | Comma separated list of methods that the CoAP consumer will bind to. The default is to bind to all methods (DELETE, GET, POST, PUT). | String | |
| exceptionHandler (consumer) | To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored. | ExceptionHandler | |
| exchangePattern (consumer) | Sets the exchange pattern when the consumer creates an exchange. | ExchangePattern | |
| synchronous (advanced) | Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). | false | boolean |
66.2. Spring Boot Auto-Configuration
The component supports 2 options, which are listed below.
| Name | Description | Default | Type |
|---|---|---|---|
| camel.component.coap.enabled | Enable coap component | true | Boolean |
| camel.component.coap.resolve-property-placeholders | Whether the component should resolve property placeholders on itself when starting. Only properties which are of String type can use property placeholders. | true | Boolean |
66.3. Message Headers
| Name | Type | Description |
|---|---|---|
|
|
| The request method that the CoAP producer should use when calling the target CoAP server URI. Valid options are DELETE, GET, PING, POST & PUT. |
|
|
| The CoAP response code sent by the external server. See RFC 7252 for details of what each code means. |
|
|
| The URI of a CoAP server to call. Will override any existing URI configured directly on the endpoint. |
66.3.1. Configuring the CoAP producer request method
The following rules determine which request method the CoAP producer will use to invoke the target URI:
-
The value of the
CamelCoapMethodheader - GET if a query string is provided on the target CoAP server URI.
- POST if the message exchange body is not null.
- GET otherwise.
