CXF Transport
Since Camel 2.8
What’s the Camel Transport for CXF
In CXF you offer or consume a webservice by defining its address. The first part of the address specifies the protocol to use. For example address="http://localhost:9000" in an endpoint configuration means your service will be offered using the http protocol on port 9000 of localhost. When you integrate Camel Tranport into CXF you get a new transport "camel". So you can specify address="camel://direct:MyEndpointName" to bind the CXF service address to a camel direct endpoint.
Technically speaking Camel transport for CXF is a component which implements the CXF transport API with the Camel core library. This allows you to easily use Camel’s routing engine and integration patterns support together with your CXF services.
Integrate Camel into CXF transport layer
To include the Camel Transport into your CXF bus you use the CamelTransportFactory. You can do this in Java as well as in Spring.
Setting up the Camel Transport in Spring
You can use the following snippet in your applicationcontext if you want to configure anything special. If you only want to activate the camel transport you do not have to do anything in your application context. As soon as you include the camel-cxf-transport.jar in your app, cxf will scan the jar and load a CamelTransportFactory for you.
<!-- you don't need to specify the CamelTransportFactory configuration as it is auto load by CXF bus -->
<bean class="org.apache.camel.component.cxf.transport.CamelTransportFactory">
<property name="bus" ref="cxf" />
<property name="camelContext" ref="camelContext" />
<!-- If checkException is true , CamelDestination will check the outMessage's
exception and set it into camel exchange. You can also override this value
in CamelDestination's configuration. The default value is false.
This option should be set true when you want to leverage the camel's error
handler to deal with fault message -->
<property name="checkException" value="true" />
<property name="transportIds">
<list>
<value>http://cxf.apache.org/transports/camel</value>
</list>
</property>
</bean>
Integrating the Camel Transport in a programmatic way
Camel transport provides a setContext method that you could use to set the Camel context into the transport factory. If you want this factory take effect, you need to register the factory into the CXF bus. Here is a full example for you.
import org.apache.cxf.Bus;
import org.apache.cxf.BusFactory;
import org.apache.cxf.transport.ConduitInitiatorManager;
import org.apache.cxf.transport.DestinationFactoryManager;
...
BusFactory bf = BusFactory.newInstance();
Bus bus = bf.createBus();
CamelTransportFactory camelTransportFactory = new CamelTransportFactory();
// set up the CamelContext which will be use by the CamelTransportFactory
camelTransportFactory.setCamelContext(context)
// if you are using CXF higher then 2.4.x the
camelTransportFactory.setBus(bus);
// if you are lower CXF, you need to register the ConduitInitiatorManager and DestinationFactoryManager like below
// register the conduit initiator
ConduitInitiatorManager cim = bus.getExtension(ConduitInitiatorManager.class);
cim.registerConduitInitiator(CamelTransportFactory.TRANSPORT_ID, camelTransportFactory);
// register the destination factory
DestinationFactoryManager dfm = bus.getExtension(DestinationFactoryManager.class);
dfm.registerDestinationFactory(CamelTransportFactory.TRANSPORT_ID, camelTransportFactory);
// set or bus as the default bus for cxf
BusFactory.setDefaultBus(bus);
Configure the destination and conduit with Spring
Namespace
The elements used to configure a Camel transport endpoint are defined
in the namespace http://cxf.apache.org/transports/camel
. It is
commonly referred to using the prefix camel
. In order to use the Camel
transport configuration elements, you will need to add the lines shown
below to the beans element of your endpoint’s configuration file. In
addition, you will need to add the configuration elements' namespace to
the xsi:schemaLocation
attribute.
Adding the Configuration Namespace
<beans ...
xmlns:camel="http://cxf.apache.org/transports/camel
...
xsi:schemaLocation="...
http://cxf.apache.org/transports/camel
http://cxf.apache.org/transports/camel.xsd
...>
The destination
element
You configure a Camel transport server endpoint using the
camel:destination
element and its children. The camel: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`.camel-destination`. The example
below shows the camel:destination
element that would be used to add
configuration for an endpoint that was specified by the WSDL fragment
<port binding="widgetSOAPBinding" name="widgetSOAPPort">
if the
endpoint’s target namespace was http://widgets.widgetvendor.net
.
camel:destination Element
...
<camel:destination name="{http://widgets/widgetvendor.net}widgetSOAPPort.http-destination>
<camelContext id="context" xmlns="http://activemq.apache.org/camel/schema/spring">
<route>
<from uri="direct:EndpointC" />
<to uri="direct:EndpointD" />
</route>
</camelContext>
</camel:destination>
<camel:destination name="{http://widgets/widgetvendor.net}widgetSOAPPort.camel-destination" camelContextId="context" />
...
The camel:destination
element for Spring has a number of child
elements that specify configuration information. They are described
below.
Element
Description
camel-spring:camelContext
You can specify the camel context in the camel destination
camel:camelContextRef
The camel context id which you want inject into the camel destination
The conduit
element
You configure a Camel transport client using the camel:conduit
element
and its children. The camel:conduit
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`.camel-conduit`. For example, the code below shows the
camel:conduit
element that would be used to add configuration for an
endpoint that was specified by the WSDL fragment
<port binding="widgetSOAPBinding" name="widgetSOAPPort">
if the
endpoint’s target namespace was http://widgets.widgetvendor.net
.
http-conf:conduit Element
...
<camelContext id="conduit_context" xmlns="http://activemq.apache.org/camel/schema/spring">
<route>
<from uri="direct:EndpointA" />
<to uri="direct:EndpointB" />
</route>
</camelContext>
<camel:conduit name="{http://widgets/widgetvendor.net}widgetSOAPPort.camel-conduit" camelContextId="conduit_context" />
<camel:conduit name="*.camel-conduit">
<!-- you can also using the wild card to specify the camel-conduit that you want to configure -->
...
</camel:conduit>
...
The camel:conduit
element has a number of child elements that specify
configuration information. They are described below.
Element
Description
camel-spring:camelContext
You can specify the camel context in the camel conduit
camel:camelContextRef
The camel context id which you want inject into the camel conduit
Configure the destination and conduit with Blueprint
Camel Transport for CXF supports configuration with Blueprint.
If you are using blueprint, you should use the namespace
http://cxf.apache.org/transports/camel/blueprint
and import the schema
like the blow.
Adding the Configuration Namespace for blueprint
<beans ...
xmlns:camel="http://cxf.apache.org/transports/camel/blueprint"
...
xsi:schemaLocation="...
http://cxf.apache.org/transports/camel/blueprint
http://cxf.apache.org/schmemas/blueprint/camel.xsd
...>
In blueprint camel:conduit
camel:destination
only has one
camelContextId attribute, they doesn’t support to specify the camel
context in the camel destination.
<camel:conduit id="*.camel-conduit" camelContextId="camel1" />
<camel:destination id="*.camel-destination" camelContextId="camel1" />
Example Using Camel as a load balancer for CXF
This example shows how to use the camel load balancing feature in CXF. You need to load the configuration file in CXF and publish the endpoints on the address "camel://direct:EndpointA" and "camel://direct:EndpointB"
Spring Boot Auto-Configuration
When using cxf-transport 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-transport-starter</artifactId>
<version>x.x.x</version>
<!-- use the same version as your Camel core version -->
</dependency>
The component has no Spring Boot auto configuration options.