Invoke system function: Web Services-ReliableMessaging

You can use WS-ReliableMessaging technology to provide assurance that an Invoke message is received by the target Web Service. To achieve the reliability, a standardized series of messages is exchanged between the sender and the receiver. In addition, each message is sent repeatedly until the expected acknowledgement message is received.

About this task

WS-ReliableMessaging results in a minimum of five messages for every request, plus more messages if retransmissions are necessary. Therefore, use WS-ReliableMessaging only for requests that warrant this type of handling.

Support for reliable messaging varies in the following ways:

For workflows that you created with Content Cortex Process Engine version 4.0, all Receive and Reply system functions support both Reliable Messaging and non-Reliable Messaging requests.
For workflows that you created with previous versions of workflow system, the Receive and Reply system functions do not support reliable messaging.
The web services of an independent software vendor might not support reliable messaging. It is the responsibility of the workflow author to determine whether this functionality is available. If you specify reliable messaging and this functionality is not available in the invoked web service, a run time error occurs. This error causes the work item to be routed to the Conductor queue.

Tip: If the message is not delivered in the specified time limit, a fault is returned in the same manner as for standard requests. The returned fault does not include workflow system exception codes, only the exception message. For a reliable messaging request, the fault message includes the current state of the reliable message invocation, which helps to identify where the problems are occurring. Therefore, to realize the benefit of reliable messaging, handle any faults appropriately.

Procedure

To specify WS-Reliable Messaging for the Invoke function:

Select the Use reliable messaging check box.

Optional: On the Faults tab, you can handle faults in the following ways:

Specific faults	If the Web Service that you are invoking defines specific faults, specify a string field or XML data field and a submap for one or more messages.
Non-specific faults	Some faults are not identified by the web service, such as timeout situations and other unanticipated faults. For unexpected problems with an invocation that uses WS-ReliableMessaging, the status message is appended to this fault message. To handle these types of faults, specify a string data field or XML data field for the message. Also, you can specify a submap. If no submap is specified and a fault occurs, the work item is routed to the Malfunction queue.

Specific faults

If the Web Service that you are invoking defines specific faults, specify a string field or XML data field and a submap for one or more messages.

Non-specific faults

Some faults are not identified by the web service, such as timeout situations and other unanticipated faults. For unexpected problems with an invocation that uses WS-ReliableMessaging, the status message is appended to this fault message.

To handle these types of faults, specify a string data field or XML data field for the message. Also, you can specify a submap. If no submap is specified and a fault occurs, the work item is routed to the Malfunction queue.