This topic describes a scenario in which an MQGet node is used in a request-response flow, and explains how the node processes the input messages to construct the output messages, based on both the content of the LocalEnvironment tree and the input parameters that you set.
You can include an MQGet node anywhere in a message flow, including a flow that implements a request-response scenario. The node receives an input message on its input terminal from the preceding node in the message flow. It issues an MQGET call to retrieve a message from the WebSphere MQ queue that you have configured in its properties, and builds a result message tree. Finally, it uses the input tree and the result tree to create an output tree that is then propagated to its Output, Warning, or Failure terminal, depending on the configuration of the node and the result of the MQGET operation.
The MQGet node examines the LocalEnvironment tree that is propagated from the preceding node. It uses the content related to the MQGMO (MQ Get Message Options) and the MQMD (MQ Message Descriptor header), and updates the LocalEnvironment:
Set the value to ${inputMQParmsLocation} in the MQGet node property Input MQ Parameters Location on the Request Properties tab.
Set the value to ${outputMQParmsLocation} in the MQGet node property Output MQ Parameters Location on the Result Properties tab.
If you want more information about the properties of the MQGet node see the Related links.
The following diagram shows how the MQGet node constructs the MQMD that is used on the call to WebSphere MQ:
The following diagram outlines how the MQGet node constructs the output message tree, combining the input tree from the previous node with the result tree from the MQGET call:
Property | Action |
---|---|
Copy Message | Copy Entire Message |
Generate Mode | Message |
Output Data Location | OutputRoot.XMLNS.A |
Result Data Location | ResultRoot.XMLNS.C |
The following diagram illustrates this:
For some examples of message trees that are constructed by the MQGet node according to the rules described above, see the Related links.