19.5. Configuring WS-RM

19.5.1. Configuring Apache CXF-Specific WS-RM Attributes

Overview

To configure the Apache CXF-specific attributes, use the rmManager Spring bean. Add the following to your configuration file:
  • The http://cxf.apache.org/ws/rm/manager namespace to your list of namespaces.
  • An rmManager Spring bean for the specific attribute that your want to configure.

Example 19.4. Configuring Apache CXF-Specific WS-RM Attributes

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager"
      xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
 http://cxf.apache.org/ws/rm/manager http://cxf.apache.org/schemas/configuration/wsrm-manager.xsd">
...
<wsrm-mgr:rmManager>
<!--
  ...Your configuration goes here
-->
</wsrm-mgr:rmManager>

Children of the rmManager Spring bean

Table 19.2, “Children of the rmManager Spring Bean” shows the child elements of the rmManager Spring bean, defined in the http://cxf.apache.org/ws/rm/manager namespace.

Table 19.2. Children of the rmManager Spring Bean

ElementDescription
RMAssertionAn element of type RMAssertion
deliveryAssuranceAn element of type DeliveryAssuranceType that describes the delivery assurance that should apply
sourcePolicyAn element of type SourcePolicyType that allows you to configure details of the RM source
destinationPolicyAn element of type DestinationPolicyType that allows you to configure details of the RM destination

Example

19.5.2. Configuring Standard WS-RM Policy Attributes

Overview

You can configure standard WS-RM policy attributes in one of the following ways:

WS-Policy RMAssertion Children

Table 19.3, “Children of the WS-Policy RMAssertion Element” shows the elements defined in the http://schemas.xmlsoap.org/ws/2005/02/rm/policy namespace:

Table 19.3. Children of the WS-Policy RMAssertion Element

NameDescription
InactivityTimeout Specifies the amount of time that must pass without receiving a message before an endpoint can consider an RM sequence to have been terminated due to inactivity.
BaseRetransmissionInterval Sets the interval within which an acknowledgement must be received by the RM Source for a given message. If an acknowledgement is not received within the time set by the BaseRetransmissionInterval, the RM Source will retransmit the message.
ExponentialBackoff
Indicates the retransmission interval will be adjusted using the commonly known exponential backoff algorithm (Tanenbaum).
For more information, see Computer Networks, Andrew S. Tanenbaum, Prentice Hall PTR, 2003.
AcknowledgementInterval In WS-RM, acknowledgements are sent on return messages or sent stand-alone. If a return message is not available to send an acknowledgement, an RM Destination can wait for up to the acknowledgement interval before sending a stand-alone acknowledgement. If there are no unacknowledged messages, the RM Destination can choose not to send an acknowledgement.

More detailed reference information

For more detailed reference information, including descriptions of each element’s sub-elements and attributes, please refer to http://schemas.xmlsoap.org/ws/2005/02/rm/wsrm-policy.xsd.

RMAssertion in rmManager Spring bean

You can configure standard WS-RM policy attributes by adding an RMAssertion within a Apache CXF rmManager Spring bean. This is the best approach if you want to keep all of your WS-RM configuration in the same configuration file; that is, if you want to configure Apache CXF-specific attributes and standard WS-RM policy attributes in the same file.
  • A standard WS-RM policy attribute, BaseRetransmissionInterval, configured using an RMAssertion within an rmManager Spring bean.
  • An Apache CXF-specific RM attribute, intraMessageThreshold, configured in the same configuration file.

Example 19.5. Configuring WS-RM Attributes Using an RMAssertion in an rmManager Spring Bean

<beans xmlns:wsrm-policy="http://schemas.xmlsoap.org/ws/2005/02/rm/policy"
       xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager"
...>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <wsrm-policy:RMAssertion>
        <wsrm-policy:BaseRetransmissionInterval Milliseconds="4000"/>
    </wsrm-policy:RMAssertion>
    <wsrm-mgr:destinationPolicy>
        <wsrm-mgr:acksPolicy intraMessageThreshold="0" />
    </wsrm-mgr:destinationPolicy>
</wsrm-mgr:rmManager>
</beans>

Policy within a feature

You can configure standard WS-RM policy attributes within features, as shown in Example 19.6, “Configuring WS-RM Attributes as a Policy within a Feature”.

Example 19.6. Configuring WS-RM Attributes as a Policy within a Feature

<xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:wsa="http://cxf.apache.org/ws/addressing"
        xmlns:wsp="http://www.w3.org/2006/07/ws-policy"
        xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"
        xmlns:jaxws="http://cxf.apache.org/jaxws"
        xsi:schemaLocation="
http://www.w3.org/2006/07/ws-policy http://www.w3.org/2006/07/ws-policy.xsd
http://cxf.apache.org/ws/addressing http://cxf.apache.org/schema/ws/addressing.xsd
http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
    <jaxws:endpoint name="{http://cxf.apache.org/greeter_control}GreeterPort" createdFromAPI="true">
        <jaxws:features>
               <wsp:Policy>
                   <wsrm:RMAssertion xmlns:wsrm="http://schemas.xmlsoap.org/ws/2005/02/rm/policy">
                     <wsrm:AcknowledgementInterval Milliseconds="200" />
                   </wsrm:RMAssertion>
                   <wsam:Addressing xmlns:wsam="http://www.w3.org/2007/02/addressing/metadata">
                       <wsp:Policy>
                            <wsam:NonAnonymousResponses/>
                       </wsp:Policy>
                   </wsam:Addressing>
              </wsp:Policy>
        </jaxws:features>
    </jaxws:endpoint>
</beans>

WSDL file

If you use the WS-Policy framework to enable WS-RM, you can configure standard WS-RM policy attributes in a WSDL file. This is a good approach if you want your service to interoperate and use WS-RM seamlessly with consumers deployed to other policy-aware Web services stacks.
For an example, see the section called “WS-Policy framework: implicitly adding interceptors” where the base retransmission interval is configured in the WSDL file.

External attachment

You can configure standard WS-RM policy attributes in an external attachment file. This is a good approach if you cannot, or do not want to, change your WSDL file.
Example 19.7, “Configuring WS-RM in an External Attachment” shows an external attachment that enables both WS-A and WS-RM (base retransmission interval of 30 seconds) for a specific EPR.

Example 19.7. Configuring WS-RM in an External Attachment

<attachments xmlns:wsp="http://www.w3.org/2006/07/ws-policy" xmlns:wsa="http://www.w3.org/2005/08/addressing">
    <wsp:PolicyAttachment>
        <wsp:AppliesTo>
           <wsa:EndpointReference>
                <wsa:Address>http://localhost:9020/SoapContext/GreeterPort</wsa:Address>
            </wsa:EndpointReference>
        </wsp:AppliesTo>
        <wsp:Policy>
            <wsam:Addressing xmlns:wsam="http://www.w3.org/2007/02/addressing/metadata">
                <wsp:Policy/>
            </wsam:Addressing>
            <wsrmp:RMAssertion xmlns:wsrmp="http://schemas.xmlsoap.org/ws/2005/02/rm/policy">
                <wsrmp:BaseRetransmissionInterval Milliseconds="30000"/>
            </wsrmp:RMAssertion>
        </wsp:Policy>
    </wsp:PolicyAttachment>
</attachments>/

19.5.3. WS-RM Configuration Use Cases

Overview

This subsection focuses on configuring WS-RM attributes from a use case point of view. Where an attribute is a standard WS-RM policy attribute, defined in the http://schemas.xmlsoap.org/ws/2005/02/rm/policy/ namespace, only the example of setting it in an RMAssertion within an rmManager Spring bean is shown. For details of how to set such attributes as a policy within a feature; in a WSDL file, or in an external attachment, see Section 19.5.2, “Configuring Standard WS-RM Policy Attributes”.
The following use cases are covered:

Base retransmission interval

The BaseRetransmissionInterval element specifies the interval at which an RM source retransmits a message that has not yet been acknowledged. It is defined in the http://schemas.xmlsoap.org/ws/2005/02/rm/wsrm-policy.xsd schema file. The default value is 3000 milliseconds.
Example 19.8, “Setting the WS-RM Base Retransmission Interval” shows how to set the WS-RM base retransmission interval.

Example 19.8. Setting the WS-RM Base Retransmission Interval

<beans xmlns:wsrm-policy="http://schemas.xmlsoap.org/ws/2005/02/rm/policy
...>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <wsrm-policy:RMAssertion>
        <wsrm-policy:BaseRetransmissionInterval Milliseconds="4000"/>
    </wsrm-policy:RMAssertion>
</wsrm-mgr:rmManager>
</beans>

Exponential backoff for retransmission

The ExponentialBackoff element determines if successive retransmission attempts for an unacknowledged message are performed at exponential intervals.
The presence of the ExponentialBackoff element enables this feature. An exponential backoff ratio of 2 is used by default.
Example 19.9, “Setting the WS-RM Exponential Backoff Property” shows how to set the WS-RM exponential backoff for retransmission.

Example 19.9. Setting the WS-RM Exponential Backoff Property

<beans xmlns:wsrm-policy="http://schemas.xmlsoap.org/ws/2005/02/rm/policy
...>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <wsrm-policy:RMAssertion>
        <wsrm-policy:ExponentialBackoff="4"/>
    </wsrm-policy:RMAssertion>
</wsrm-mgr:rmManager>
</beans>

Acknowledgement interval

The AcknowledgementInterval element specifies the interval at which the WS-RM destination sends asynchronous acknowledgements. These are in addition to the synchronous acknowledgements that it sends on receipt of an incoming message. The default asynchronous acknowledgement interval is 0 milliseconds. This means that if the AcknowledgementInterval is not configured to a specific value, acknowledgements are sent immediately (that is, at the first available opportunity).
Asynchronous acknowledgements are sent by the RM destination only if both of the following conditions are met:
  • The RM destination is using a non-anonymous wsrm:acksTo endpoint.
  • The opportunity to piggyback an acknowledgement on a response message does not occur before the expiry of the acknowledgement interval.
Example 19.10, “Setting the WS-RM Acknowledgement Interval” shows how to set the WS-RM acknowledgement interval.

Example 19.10. Setting the WS-RM Acknowledgement Interval

<beans xmlns:wsrm-policy="http://schemas.xmlsoap.org/ws/2005/02/rm/policy
...>
<wsrm-mgr:rmManager id="org.apache.cxf.ws.rm.RMManager">
    <wsrm-policy:RMAssertion>
        <wsrm-policy:AcknowledgementInterval Milliseconds="2000"/>
    </wsrm-policy:RMAssertion>
</wsrm-mgr:rmManager>
</beans>

Maximum unacknowledged messages threshold

The maxUnacknowledged attribute sets the maximum number of unacknowledged messages that can accrue per sequence before the sequence is terminated.
Example 19.11, “Setting the WS-RM Maximum Unacknowledged Message Threshold” shows how to set the WS-RM maximum unacknowledged messages threshold.

Example 19.11. Setting the WS-RM Maximum Unacknowledged Message Threshold

<beans xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager
...>
<wsrm-mgr:reliableMessaging>
    <wsrm-mgr:sourcePolicy>
        <wsrm-mgr:sequenceTerminationPolicy maxUnacknowledged="20" />
    </wsrm-mgr:sourcePolicy>
</wsrm-mgr:reliableMessaging>
</beans>

Maximum length of an RM sequence

The maxLength attribute sets the maximum length of a WS-RM sequence. The default value is 0, which means that the length of a WS-RM sequence is unbound.
When this attribute is set, the RM endpoint creates a new RM sequence when the limit is reached, and after receiving all of the acknowledgements for the previously sent messages. The new message is sent using a newsequence.
Example 19.12, “Setting the Maximum Length of a WS-RM Message Sequence” shows how to set the maximum length of an RM sequence.

Example 19.12. Setting the Maximum Length of a WS-RM Message Sequence

<beans xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager
...>
<wsrm-mgr:reliableMessaging>
    <wsrm-mgr:sourcePolicy>
        <wsrm-mgr:sequenceTerminationPolicy maxLength="100" />
    </wsrm-mgr:sourcePolicy>
</wsrm-mgr:reliableMessaging>
</beans>

Message delivery assurance policies

You can configure the RM destination to use the following delivery assurance policies:
  • AtMostOnce — The RM destination delivers the messages to the application destination only once. If a message is delivered more than once an error is raised. It is possible that some messages in a sequence may not be delivered.
  • AtLeastOnce — The RM destination delivers the messages to the application destination at least once. Every message sent will be delivered or an error will be raised. Some messages might be delivered more than once.
  • InOrder — The RM destination delivers the messages to the application destination in the order that they are sent. This delivery assurance can be combined with the AtMostOnce or AtLeastOnce assurances.
Example 19.13, “Setting the WS-RM Message Delivery Assurance Policy” shows how to set the WS-RM message delivery assurance.

Example 19.13. Setting the WS-RM Message Delivery Assurance Policy

<beans xmlns:wsrm-mgr="http://cxf.apache.org/ws/rm/manager
...>
<wsrm-mgr:reliableMessaging>
    <wsrm-mgr:deliveryAssurance>
        <wsrm-mgr:AtLeastOnce />
    </wsrm-mgr:deliveryAssurance>
</wsrm-mgr:reliableMessaging>
</beans>