Oracle SALT WS-ReliableMessaging Policy Assertion Reference

The following sections provide SALT WS-ReliableMessaging (WS-RM) Policy Assertion reference information:

•

Overview

•	WS-RM Policy Assertion Format

•	WS-RM Assertion File Example

•	WS-RM Assertion Element Description

Overview

Oracle SALT provides support for WS-ReliableMessaging (WS-ReliableMessaging 1.0, Feb., 2005 specification), which allows two Web Service applications running on different GWWS instances to communicate reliably in the event of software component, system, or networks failure.

A WS-Policy file containing WS-ReliableMessaging Policy Assertion is used to configure the reliable messaging capabilities of a GWWS server on a destination endpoint. SALT supports the WS-ReliableMessaging Policy Assertion specification to ensure the interoperability with Oracle WebLogic 9.x / 10.

For more information about configuring a reliable GWWS server, see “Configuring Advanced Web Service Messaging Features in the Oracle SALT Administration Guide.

WS-RM Policy Assertion Format

Figure C‑1 shows a graphical representation of the WS-ReliableMessaging Policy Assertion format in a WS-Policy file.

Figure C‑1 WS-ReliableMessaging Policy Assertion Format

WS-RM Assertion File Example

Listing C‑1 shows a sample WS-Policy file that contains WS-RM policy assertion.

Listing C‑1 Sample WS-ReliableMessaging Policy Assertion File

<?xml version="1.0"?>
<wsp:Policy wsp:Name="ReliableSomeServicePolicy"
  xmlns:wsrm="http://schemas.xmlsoap.org/ws/2005/02/rm"
  xmlns:wsp="http://schemas.xmlsoap.org/ws/2004/09/policy"
  xmlns:beapolicy="http://www.bea.com/wsrm/policy">
  <wsrm:RMAssertion>
    <wsrm:InactivityTimeout Milliseconds="600000" />
    <wsrm:BaseRetransmissionInterval Milliseconds="500"/>
    <wsrm:ExponentialBackoff />
    <wsrm:AcknowledgementInterval Milliseconds="2000" />
    <beapolicy:Expires Expires="P1D" />
    <beapolicy:QOS QOS="ExactlyOnce InOrder" />
  </wsrm:RMAssertion>
</wsp:Policy>

 

WS-RM Assertion Element Description

All RM assertions are optional, and if not specified, the default value are used. The following definitions describe the RM assertion options.

<wsrm:InactivityTimeout>

Specifies the number of milliseconds, specified with the Milliseconds attribute, which defines an inactivity interval. After time has elapsed, if the destination endpoint has not received a message from the source endpoint, the destination endpoint may terminate current sequence due to inactivity. The source endpoint can also use this parameter.

Sequences never time out by default.

<wsrm:AcknowledgementInterval>

Specifies the maximum interval, in milliseconds, in which the destination endpoint must transmit a stand-alone acknowledgement.

This element is optional. If this element is not specified, There is no time limit by default.

<wsrm:BaseRetransmissionInterval>

Specifies the interval, in milliseconds, that the source endpoint waits after transmitting a message and before it retransmits the message if it receives no acknowledgment for that message. This value will apply to the GWWS server when it sends a response in an outbound sequence.

The default value is 20000 milliseconds.

<wsrm:ExponentialBackoff>

Specifies that the retransmission interval is adjusted using the exponential back off algorithm. This value applies to the GWWS server when it sends a response in an outbound sequence.

<beapolicy:Expires>

Specifies the amount of time after which the reliable Web service expires and does not accept any new sequence messages.

This element has a single attribute, Expires, whose data type is an XML Schema duration type. For example, if you want to set the expiration time to one day, use the following:

< beapolicy:Expires Expires="P1D" />

The default value is never expire.

<beapolicy:QOS>

Specifies the delivery assurance. SALT supports the following assurances:

•	AtMostOnce - Messages are delivered at most once, without duplication. There is possibility that some messages may not be delivered.

•	AtLeastOnce - Every message is delivered at least once. There is possibility that some messages are delivered more than once.

•	ExactlyOnce - Each message is delivered exactly once, without duplication.

•	InOrder - Messages are delivered in the order that they were sent. This delivery assurance can be combined with one of the preceding three assurances.

The default value is "ExactlyOnce InOrder".

<wsrm:RMAssertion>

Main WS-RM assertion that groups all the other assertions under a single element.

The presence of this assertion in a WS-Policy file indicates that the corresponding Web Service application must be invoked reliably.