When more than one CXF endpoint appears in a route, you need to decide whether or not to allow headers to propagate between the endpoints. By default, the headers are relayed back and forth between the endpoints, but in many cases it might be necessary to filter the headers or to block them altogether. You can control header propagation by applying filters to producer endpoints.

Header filtering is controlled by the CxfHeaderFilterStrategy class. Basic configuration of the CxfHeaderFilterStrategy class involves setting one or more of the following options:

The semantics of the relayHeaders option can be summarized as follows:

An in-band header is a header that is explicitly defined as part of the WSDL binding contract for an endpoint.

An out-of-band header is a header that is serialized over the wire, but is not explicitly part of the WSDL binding contract. In particular, the SOAP binding permits out-of-band headers, because the SOAP specification does not require headers to be defined in the WSDL contract.

The CXF endpoint's payload format affects the filter behavior as follows:

The default filter is of type, SoapMessageHeaderFilter, which removes only the SOAP headers that the SOAP specification expects an intermediate Web service to consume. For more details, see SoapMessageHeaderFilter.

You can override the default CxfHeaderFilterStrategy instance by defining a new CxfHeaderFilterStrategy bean and associating it with a CXF endpoint.

The following example shows how you can use the relayHeaders option to create a CxfHeaderFilterStrategy bean that blocks all message headers. The CXF endpoints in the route use the headerFilterStrategy option to install the filter strategy in the endpoint, where the headerFilterStrategy setting has the syntax, headerFilterStrategy=#BeanID.

<beans ...>
  ...
  <bean id="dropAllMessageHeadersStrategy" class="org.apache.camel.component.cxf.common.header.CxfHeaderFilterStrategy">
      <!--  Set relayHeaders to false to drop all SOAP headers -->
      <property name="relayHeaders" value="false"/>
  </bean>

  <camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
      <route>
          <from uri="cxf:bean:routerNoRelayEndpoint?headerFilterStrategy=#dropAllMessageHeadersStrategy"/>
          <to uri="cxf:bean:serviceNoRelayEndpoint?headerFilterStrategy=#dropAllMessageHeadersStrategy"/>
      </route>
  </camelContext>
  ...
</beans>

The relayAllMessageHeaders option is used to propagate all SOAP headers, without applying any filtering (any installed filters would be bypassed). In order to enable this feature, you must set both relayHeaders and relayAllMessageHeaders to true.

The following example shows how to configure CXF endpoints to propagate all SOAP message headers. The propagateAllMessages filter strategy sets both relayHeaders and relayAllMessageHeaders to true.

<beans ...>
  ...
  <bean id="propagateAllMessages" class="org.apache.camel.component.cxf.common.header.CxfHeaderFilterStrategy">
      <!--  Set both properties to true to propagate *all* SOAP headers -->
      <property name="relayHeaders" value="true"/>
      <property name="relayAllMessageHeaders" value="true"/>
  </bean>

  <camelContext id="camel" xmlns="http://camel.apache.org/schema/spring">
      <route>
          <from uri="cxf:bean:routerNoRelayEndpoint?headerFilterStrategy=#propagateAllMessages"/>
          <to uri="cxf:bean:serviceNoRelayEndpoint?headerFilterStrategy=#propagateAllMessages"/>
      </route>
  </camelContext>
  ...
</beans>