Creating the Publication Message Flow IBM-CICS

As mentioned in the WMB overview, Message Flows are the way we program WMB. Message flows are sequences of Nodes that perform functions, connected together.

The message flow needs to be defined in a separate Message Flow project. (File → New → Message Flow Project). We need to specify the dependencies this project has on other projects that contain message definitions we require, specifically the CICSWSAPMQMsgSet project.

Message Flow project references

Message Flow project references

Our publication message flow will be very straightforward. We simply need to take a publication message of the CICSWSAP.PUBLICATION.QUEUE queue and publish it. In order to publish the message, WMB first needs to be able to understand the message. This is why we needed to create the CICSWSAPMQMsgSet message set and import the structure. We used the following message flow to perform our publication.

We created the Message Flow project and now a Message Flow called HashPublication. With this, the message flow editor opens with a blank canvas

The Hash Publication Message Flow

The Hash Publication Message Flow

Construction of this Message Flow is a simple matter of dropping the required nodes onto the canvas, connecting the nodes, and renaming nodes as appropriate. Of the three terminals of the MQInput node (Get Pub Msg), we have the failure terminal connected to the Trace node named BadMQFormat. The trace node is configured to write the message tree out to the local error log, which is viewed using the EventVwr utility in Windows. This gives us a chance to observe erroneous messages passed from the UpdateAddress CICS application. The MQInput’s Out terminal is connected to the Publication node (Publish Hash).

The MQInput node has the basic properties shown in Figure above and the default properties shown in Figure below.

MQInput Node - Basic Properties

MQInput Node - Basic Properties

The MQInput node - Default Properties

The MQInput node - Default Properties

Each of these properties are essential to the correct operation of the MQInput node and subsequent publication of the message. We must tell the MQInput node from what queue to take messages. We must indicate the message set that tells WMB about the format of these messages. This format is the one we created by importing the C header file containing the C structure. The other piece of critical information is to define for what pub/sub topic this message is destined.

The Publication node contains just one configuration item—the Subscription point.

The Publication node properties

The Publication node properties

We deployed this message flow, together with the CICSWSAPMQMsgSet—termed a dictionary in the broker archive (BAR) file.

Assuming required queues are defined, channels running and subscriptions made, our pub/sub environment is now ready.


Face Book Twitter Google Plus Instagram Youtube Linkedin Myspace Pinterest Soundcloud Wikipedia

All rights reserved © 2018 Wisdom IT Services India Pvt. Ltd DMCA.com Protection Status

IBM-CICS Topics