CXF-RS
Since Camel 2.0
Both producer and consumer are supported
The CXFRS component provides integration with Apache CXF for connecting to JAX-RS 1.1 and 2.0 services hosted in CXF.
Maven users will need to add the following dependency to their pom.xml for this component:
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-cxf</artifactId>
<version>x.x.x</version> <!-- use the same version as your Camel core version -->
</dependency>
URI format
cxfrs://address?options
Where address represents the CXF endpoint’s address
cxfrs:bean:rsEndpoint
Where rsEndpoint represents the spring bean’s name which presents the CXFRS client or server
For either style above, you can append options to the URI as follows:
cxfrs:bean:cxfEndpoint?resourceClasses=org.apache.camel.rs.Example
Configuring Options
Camel components are configured on two separate levels:
-
component level
-
endpoint level
Configuring Component Options
The component level is the highest level which holds general and common configurations that are inherited by the endpoints. For example a component may have security settings, credentials for authentication, urls for network connection and so forth.
Some components only have a few options, and others may have many. Because components typically have pre configured defaults that are commonly used, then you may often only need to configure a few options on a component; or none at all.
Configuring components can be done with the Component DSL, in a configuration file (application.properties|yaml), or directly with Java code.
Configuring Endpoint Options
Where you find yourself configuring the most is on endpoints, as endpoints often have many options, which allows you to configure what you need the endpoint to do. The options are also categorized into whether the endpoint is used as consumer (from) or as a producer (to), or used for both.
Configuring endpoints is most often done directly in the endpoint URI as path and query parameters. You can also use the Endpoint DSL as a type safe way of configuring endpoints.
A good practice when configuring options is to use Property Placeholders, which allows to not hardcode urls, port numbers, sensitive information, and other settings. In other words placeholders allows to externalize the configuration from your code, and gives more flexibility and reuse.
The following two sections lists all the options, firstly for the component followed by the endpoint.
Component Options
The CXF-RS component supports 5 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
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 |
|
Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. |
false |
boolean |
|
Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. |
true |
boolean |
|
To use a custom org.apache.camel.spi.HeaderFilterStrategy to filter header to and from Camel message. |
HeaderFilterStrategy |
||
Enable usage of global SSL context parameters. |
false |
boolean |
Endpoint Options
The CXF-RS endpoint is configured using URI syntax:
cxfrs:beanId:address
with the following path and query parameters:
Query Parameters (31 parameters)
Name | Description | Default | Type |
---|---|---|---|
Set the feature list to the CxfRs endpoint. |
List |
||
This option enables CXF Logging Feature which writes inbound and outbound REST messages to log. |
false |
boolean |
|
To limit the total size of number of bytes the logger will output when logging feature has been enabled. |
int |
||
This option is used to specify the model file which is useful for the resource class without annotation. When using this option, then the service class can be omitted, to emulate document-only endpoints. |
String |
||
Set custom JAX-RS provider(s) list to the CxfRs endpoint. You can specify a string with a list of providers to lookup in the registy separated by comma. |
String |
||
The resource classes which you want to export as REST service. Multiple classes can be separated by comma. |
List |
||
Sets the locations of the schema(s) which can be used to validate the incoming XML or JAXB-driven JSON. |
List |
||
This option controls whether the PhaseInterceptorChain skips logging the Fault that it catches. |
false |
boolean |
|
Sets how requests and responses will be mapped to/from Camel. Two values are possible: SimpleConsumer: This binding style processes request parameters, multiparts, etc. and maps them to IN headers, IN attachments and to the message body. It aims to eliminate low-level processing of org.apache.cxf.message.MessageContentsList. It also also adds more flexibility and simplicity to the response mapping. Only available for consumers. Default: The default style. For consumers this passes on a MessageContentsList to the route, requiring low-level processing in the route. This is the traditional binding style, which simply dumps the org.apache.cxf.message.MessageContentsList coming in from the CXF stack onto the IN message body. The user is then responsible for processing it according to the contract defined by the JAX-RS method signature. Custom: allows you to specify a custom binding through the binding option. Enum values:
|
Default |
BindingStyle |
|
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 |
|
This option can override the endpointUrl that published from the WADL which can be accessed with resource address url plus _wadl. |
String |
||
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 |
||
Sets the exchange pattern when the consumer creates an exchange. Enum values:
|
ExchangePattern |
||
The service beans (the bean ids to lookup in the registry) which you want to export as REST service. Multiple beans can be separated by comma. |
String |
||
Configure a cookie handler to maintain a HTTP session. |
CookieHandler |
||
The hostname verifier to be used. Use the # notation to reference a HostnameVerifier from the registry. |
HostnameVerifier |
||
Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. |
false |
boolean |
|
The Camel SSL setting reference. Use the # notation to reference the SSL Context. |
SSLContextParameters |
||
This option tells the CxfRsProducer to inspect return codes and will generate an Exception if the return code is larger than 207. |
true |
boolean |
|
If it is true, the CxfRsProducer will use the HttpClientAPI to invoke the service. If it is false, the CxfRsProducer will use the ProxyClientAPI to invoke the service. |
true |
boolean |
|
This option is used to tell CxfRsProducer to ignore the message body of the DELETE method when using HTTP API. |
false |
boolean |
|
This option allows you to configure the maximum size of the cache. The implementation caches CXF clients or ClientFactoryBean in CxfProvider and CxfRsProvider. |
10 |
int |
|
Sets whether synchronous processing should be strictly used. |
false |
boolean |
|
To use a custom CxfBinding to control the binding between Camel Message and CXF Message. |
CxfRsBinding |
||
To use a custom configured CXF Bus. |
Bus |
||
This option is used to set the CXF continuation timeout which could be used in CxfConsumer by default when the CXF server is using Jetty or Servlet transport. |
30000 |
long |
|
This option could apply the implementation of org.apache.camel.component.cxf.jaxrs.CxfRsEndpointConfigurer which supports to configure the CXF endpoint in programmatic way. User can configure the CXF server and client by implementing configure\{Server/Client} method of CxfEndpointConfigurer. |
CxfRsConfigurer |
||
Will set the default bus when CXF endpoint create a bus by itself. |
false |
boolean |
|
To use a custom HeaderFilterStrategy to filter header to and from Camel message. |
HeaderFilterStrategy |
||
When the option is true, Camel will perform the invocation of the resource class instance and put the response object into the exchange for further processing. |
false |
boolean |
|
When the option is true, JAXRS UriInfo, HttpHeaders, Request and SecurityContext contexts will be available to custom CXFRS processors as typed Camel exchange properties. These contexts can be used to analyze the current requests using JAX-RS API. |
false |
boolean |
Message Headers
The CXF-RS component supports 16 message header(s), which is/are listed below:
Name | Description | Default | Type |
---|---|---|---|
The name of the operation. |
String |
||
The authentication. |
Subject |
||
The http method to use. |
String |
||
The http path. |
String |
||
The content type. |
String |
||
The http query. |
String |
||
The http response code. |
Integer |
||
The content encoding. |
String |
||
The protocol headers. |
Map |
||
The CXF message. |
Message |
||
If it is true, the CxfRsProducer will use the HttpClientAPI to invoke the service. If it is false, the CxfRsProducer will use the ProxyClientAPI to invoke the service. |
Boolean |
||
The path values. |
Object[] |
||
The response class. |
Class |
||
The response generic type. |
Type |
||
The query map. |
Map |
||
The stack of MethodInvocationInfo representing resources path when JAX-RS invocation looks for target. |
OperationResourceInfoStack |
You can also configure the CXF REST endpoint through the spring configuration. Since there are lots of difference between the CXF REST client and CXF REST Server, we provide different configuration for them. Please check out the schema file and CXF JAX-RS documentation for more information.
How to configure the REST endpoint in Camel
In
camel-cxf
schema file, there are two elements for the REST endpoint definition.
cxf:rsServer for REST consumer, cxf:rsClient for REST producer.
You can find a Camel REST service route configuration example here.
How to override the CXF producer address from message header
The camel-cxfrs
producer supports to override the services address by
setting the message with the key of "CamelDestinationOverrideUrl".
// set up the service address from the message header to override the setting of CXF endpoint
exchange.getIn().setHeader(Exchange.DESTINATION_OVERRIDE_URL, constant(getServiceAddress()));
Consuming a REST Request - Simple Binding Style
Since Camel 2.11
The Default
binding style is rather low-level, requiring the user to
manually process the MessageContentsList
object coming into the route.
Thus, it tightly couples the route logic with the method signature and
parameter indices of the JAX-RS operation. Somewhat inelegant, difficult
and error-prone.
In contrast, the SimpleConsumer
binding style performs the following
mappings, in order to make the request data more accessible to you
within the Camel Message:
-
JAX-RS Parameters (@HeaderParam, @QueryParam, etc.) are injected as IN message headers. The header name matches the value of the annotation.
-
The request entity (POJO or other type) becomes the IN message body. If a single entity cannot be identified in the JAX-RS method signature, it falls back to the original
MessageContentsList
. -
Binary
@Multipart
body parts become IN message attachments, supportingDataHandler
,InputStream
,DataSource
and CXF’sAttachment
class. -
Non-binary
@Multipart
body parts are mapped as IN message headers. The header name matches the Body Part name.
Additionally, the following rules apply to the Response mapping:
-
If the message body type is different to
javax.ws.rs.core.Response
(user-built response), a newResponse
is created and the message body is set as the entity (so long it’s not null). The response status code is taken from theExchange.HTTP_RESPONSE_CODE
header, or defaults to 200 OK if not present. -
If the message body type is equal to
javax.ws.rs.core.Response
, it means that the user has built a custom response, and therefore it is respected and it becomes the final response. -
In all cases, Camel headers permitted by custom or default
HeaderFilterStrategy
are added to the HTTP response.
Enabling the Simple Binding Style
This binding style can be activated by setting the bindingStyle
parameter in the consumer endpoint to value SimpleConsumer
:
from("cxfrs:bean:rsServer?bindingStyle=SimpleConsumer")
.to("log:TEST?showAll=true");
Examples of request binding with different method signatures
Below is a list of method signatures along with the expected result from the Simple binding.
public Response doAction(BusinessObject request);
Request payload is placed in IN message body, replacing the original
MessageContentsList.
public Response doAction(BusinessObject request, @HeaderParam("abcd") String abcd, @QueryParam("defg") String defg);
Request payload placed in IN message body, replacing the original
MessageContentsList. Both request params mapped as IN message headers
with names abcd and defg.
public Response doAction(@HeaderParam("abcd") String abcd, @QueryParam("defg") String defg);
Both request params mapped as IN message headers with names abcd and
defg. The original MessageContentsList is preserved, even though it only
contains the 2 parameters.
public Response doAction(@Multipart(value="body1") BusinessObject request, @Multipart(value="body2") BusinessObject request2);
The first parameter is transferred as a header with name body1, and the
second one is mapped as header body2. The original MessageContentsList
is preserved as the IN message body.
public Response doAction(InputStream abcd);
The InputStream is unwrapped from the MessageContentsList and preserved
as the IN message body.
public Response doAction(DataHandler abcd);
The DataHandler is unwrapped from the MessageContentsList and preserved
as the IN message body.
More examples of the Simple Binding Style
Given a JAX-RS resource class with this method:
@POST @Path("/customers/{type}")
public Response newCustomer(Customer customer, @PathParam("type") String type, @QueryParam("active") @DefaultValue("true") boolean active) {
return null;
}
Serviced by the following route:
from("cxfrs:bean:rsServer?bindingStyle=SimpleConsumer")
.recipientList(simple("direct:${header.operationName}"));
from("direct:newCustomer")
.log("Request: type=${header.type}, active=${header.active}, customerData=${body}");
The following HTTP request with XML payload (given that the Customer DTO is JAXB-annotated):
POST /customers/gold?active=true Payload: <Customer> <fullName>Raul Kripalani</fullName> <country>Spain</country> <project>Apache Camel</project> </Customer>
Will print the message:
Request: type=gold, active=true, customerData=<Customer.toString() representation>
For more examples on how to process requests and write responses can be found here.
Consuming a REST Request - Default Binding Style
The CXF JAXRS front end implements the JAX-RS (JSR-311) API, so we can export the resources classes as a REST service. And we leverage the CXF Invoker API to turn a REST request into a normal Java object method invocation. You don’t need to specify the URI template within your endpoint, CXF takes care of the REST request URI to resource class method mapping according to the JSR-311 specification. All you need to do in Camel is delegate this method request to a right processor or endpoint.
Here is an example of a CXFRS route…
private static final String CXF_RS_ENDPOINT_URI =
"cxfrs://http://localhost:" + CXT + "/rest?resourceClasses=org.apache.camel.component.cxf.jaxrs.testbean.CustomerServiceResource";
private static final String CXF_RS_ENDPOINT_URI2 =
"cxfrs://http://localhost:" + CXT + "/rest2?resourceClasses=org.apache.camel.component.cxf.jaxrs.testbean.CustomerService";
private static final String CXF_RS_ENDPOINT_URI3 =
"cxfrs://http://localhost:" + CXT + "/rest3?"
+ "resourceClasses=org.apache.camel.component.cxf.jaxrs.testbean.CustomerServiceNoAnnotations&"
+ "modelRef=classpath:/org/apache/camel/component/cxf/jaxrs/CustomerServiceModel.xml";
private static final String CXF_RS_ENDPOINT_URI4 =
"cxfrs://http://localhost:" + CXT + "/rest4?"
+ "modelRef=classpath:/org/apache/camel/component/cxf/jaxrs/CustomerServiceDefaultHandlerModel.xml";
private static final String CXF_RS_ENDPOINT_URI5 =
"cxfrs://http://localhost:" + CXT + "/rest5?"
+ "propagateContexts=true&"
+ "modelRef=classpath:/org/apache/camel/component/cxf/jaxrs/CustomerServiceDefaultHandlerModel.xml";
protected RouteBuilder createRouteBuilder() throws Exception {
final Processor testProcessor = new TestProcessor();
final Processor testProcessor2 = new TestProcessor2();
final Processor testProcessor3 = new TestProcessor3();
return new RouteBuilder() {
public void configure() {
errorHandler(new NoErrorHandlerBuilder());
from(CXF_RS_ENDPOINT_URI).process(testProcessor);
from(CXF_RS_ENDPOINT_URI2).process(testProcessor);
from(CXF_RS_ENDPOINT_URI3).process(testProcessor);
from(CXF_RS_ENDPOINT_URI4).process(testProcessor2);
from(CXF_RS_ENDPOINT_URI5).process(testProcessor3);
}
};
}
And the corresponding resource class used to configure the endpoint…
Note about resource classes By default, JAX-RS resource classes are only used to configure JAX-RS properties. Methods will not be executed during routing of messages to the endpoint. Instead, it is the responsibility of the route to do all processing. |
It is sufficient to provide an interface only as opposed to a no-op service implementation class for the default mode.
If a performInvocation option is enabled, the service implementation will be invoked first, the response will be set on the Camel exchange and the route execution will continue as usual. This can be useful for integrating the existing JAX-RS implementations into Camel routes and for post-processing JAX-RS Responses in custom processors.
@Path("/customerservice/")
public interface CustomerServiceResource {
@GET
@Path("/customers/{id}/")
Customer getCustomer(@PathParam("id") String id);
@PUT
@Path("/customers/")
Response updateCustomer(Customer customer);
@Path("/{id}")
@PUT()
@Consumes({ "application/xml", "text/plain",
"application/json" })
@Produces({ "application/xml", "text/plain",
"application/json" })
Object invoke(@PathParam("id") String id,
String payload);
}
How to invoke the REST service through camel-cxfrs producer
The CXF JAXRS front end
implements
a
proxy-based client API, with this API you can invoke the remote REST
service through a proxy. The camel-cxfrs
producer is based on this
proxy
API.
You just need to specify the operation name in the message header and
prepare the parameter in the message body, the camel-cxfrs producer will
generate right REST request for you.
Here is an example:
Exchange exchange = template.send("direct://proxy", new Processor() {
public void process(Exchange exchange) throws Exception {
exchange.setPattern(ExchangePattern.InOut);
Message inMessage = exchange.getIn();
// set the operation name
inMessage.setHeader(CxfConstants.OPERATION_NAME, "getCustomer");
// using the proxy client API
inMessage.setHeader(CxfConstants.CAMEL_CXF_RS_USING_HTTP_API, Boolean.FALSE);
// set a customer header
inMessage.setHeader("key", "value");
// setup the accept content type
inMessage.setHeader(Exchange.ACCEPT_CONTENT_TYPE, "application/json");
// set the parameters , if you just have one parameter
// camel will put this object into an Object[] itself
inMessage.setBody("123");
}
});
// get the response message
Customer response = (Customer) exchange.getOut().getBody();
assertNotNull(response, "The response should not be null");
assertEquals(123, response.getId(), "Get a wrong customer id");
assertEquals("John", response.getName(), "Get a wrong customer name");
assertEquals(200, exchange.getOut().getHeader(Exchange.HTTP_RESPONSE_CODE), "Get a wrong response code");
assertEquals("value", exchange.getOut().getHeader("key"), "Get a wrong header value");
The CXF JAXRS front end also
provides
a
http centric client API. You can also invoke this API from
camel-cxfrs
producer. You need to specify the
HTTP_PATH
and
the HTTP_METHOD and
let the producer use the http centric client API by using the URI option
httpClientAPI or by setting the message header
CxfConstants.CAMEL_CXF_RS_USING_HTTP_API.
You can turn the response object to the type class specified with the
message
header CxfConstants.CAMEL_CXF_RS_RESPONSE_CLASS.
Exchange exchange = template.send("direct://http", new Processor() {
public void process(Exchange exchange) throws Exception {
exchange.setPattern(ExchangePattern.InOut)
Message inMessage = exchange.getIn();
// using the http central client API
inMessage.setHeader(CxfConstants.CAMEL_CXF_RS_USING_HTTP_API, Boolean.TRUE);
// set the Http method
inMessage.setHeader(Exchange.HTTP_METHOD, "GET");
// set the relative path
inMessage.setHeader(Exchange.HTTP_PATH, "/customerservice/customers/123");
// Specify the response class , cxfrs will use InputStream as the response object type
inMessage.setHeader(CxfConstants.CAMEL_CXF_RS_RESPONSE_CLASS, Customer.class);
// set a customer header
inMessage.setHeader("key", "value");
// since we use the Get method, so we don't need to set the message body
inMessage.setBody(null);
}
});
We also support to specify the query parameters from cxfrs URI for the CXFRS http centric client.
Exchange exchange = template.send("cxfrs://http://localhost:9003/testQuery?httpClientAPI=true&q1=12&q2=13"
To support the Dynamical routing, you can override the URI’s query parameters by using the CxfConstants.CAMEL_CXF_RS_QUERY_MAP header to set the parameter map for it.
Map<String, String> queryMap = new LinkedHashMap<>();
queryMap.put("q1", "new");
queryMap.put("q2", "world");
inMessage.setHeader(CxfConstants.CAMEL_CXF_RS_QUERY_MAP, queryMap);
Spring Boot Auto-Configuration
When using cxfrs 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-cxf-starter</artifactId>
<version>x.x.x</version>
<!-- use the same version as your Camel core version -->
</dependency>
The component supports 13 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
This option controls whether the CXF component, when running in PAYLOAD mode, will DOM parse the incoming messages into DOM Elements or keep the payload as a javax.xml.transform.Source object that would allow streaming in some cases. |
Boolean |
||
Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. |
true |
Boolean |
|
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 |
|
Whether to enable auto configuration of the cxf component. This is enabled by default. |
Boolean |
||
To use a custom org.apache.camel.spi.HeaderFilterStrategy to filter header to and from Camel message. The option is a org.apache.camel.spi.HeaderFilterStrategy type. |
HeaderFilterStrategy |
||
Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. |
false |
Boolean |
|
Enable usage of global SSL context parameters. |
false |
Boolean |
|
Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. |
true |
Boolean |
|
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 |
|
Whether to enable auto configuration of the cxfrs component. This is enabled by default. |
Boolean |
||
To use a custom org.apache.camel.spi.HeaderFilterStrategy to filter header to and from Camel message. The option is a org.apache.camel.spi.HeaderFilterStrategy type. |
HeaderFilterStrategy |
||
Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. |
false |
Boolean |
|
Enable usage of global SSL context parameters. |
false |
Boolean |