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.
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 FileNet® P8
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.