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 You can use the camel-cxf component to communicate the CXF endpoints in Camel Context, in this way we just treat CXF as a service framework library in Camel. But if you want to leverage the Camel routing and mediation engine in CXF , the best way is to treat Camel as an EIP library and put it into CXF transport layer. The Camel transport for CXF is this kind of 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.
CXF architecture in one minute
CXF is a service framework which supports lots of transports and bindings and you can easily develop and publish the service as you want. Here are two layers in the CXF runtime, one is generic messaging layer comprised of Messages, Interceptors, and InterceptorChains, the other is transport layer which hides transport specific details from the messaging layer. This two layer are build up with the service model which holds the WS* meta data. The transport layer with feed the incoming message to the message layer and consume the outgoing message from the message layer.
You can find the more information for the CXF architecture document http://cwiki.apache.org/CXF20DOC/cxf-architecture.html.
Integrate Camel's into CXF transport layer
You can initiate a camel context for the camel transport and do the routing and mediation work as you want in the CXF transport layer than pass the message to CXF Messaging layer for the WS* message handling.
What I can do with the Camel transport for CX
Configure the Camel context
Integrate Camel into CXF transport layer
To include the Camel Tranport 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 (or camel-cxf.jar if your camel version is less than 2.7.x) in your app, cxf will scan the jar and load a CamelTransportFactory for you.
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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.
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Configure the destination and conduit with Spring
Namespace
The elements used to configure an 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.
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The destination
element
You configure an 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
.
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The camel:destination
element for Spring has a number of child elements that specify configuration information. They are described below.
Element | Description |
---|---|
| You can specify the camel context in the camel destination |
| 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
.
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The camel:conduit
element has a number of child elements that specify configuration information. They are described below.
Element | Description |
---|---|
| You can specify the camel context in the camel conduit |
| The camel context id which you want inject into the camel conduit |
Configure the destination and conduit with Blueprint
From Camel 2.11.x, Camel Transport supports to be configured with Blueprint.
If you are using blueprint, you should use the the namespace http://cxf.apache.org/transports/camel/blueprint
and import the schema like the blow.
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In blueprint camel:conduit
camel:destination
only has one camelContextId attribute, they doesn't support to specify the camel context in the camel destination.
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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"
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Complete Howto and Example for attaching Camel to CXF
Better JMS Transport for CXF Webservice using Apache Camel
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