Overriding MQGet node properties during message processing

When you include and configure an MQGet node in a message flow, you might want to override its properties under some conditions. For example, you might want to read from a queue that is identified in another part of the message, or that is retrieved from a database record.

About this task

To override the values that you set for the MQGet node properties to achieve a more dynamic way to process messages, include a Compute or JavaCompute node in your message flow before the MQGet node. Configure this node to create an output message, and add fields to the local environment tree to define new values for the properties that you want to change.

For example, add a Compute node into the flow and define a new queue name for the MQGet node to read for messages, by including the following ESQL statement:
SET LocalEnvironment.MQ.GET.QueueName = 'new_queue';

Procedure

Use OutputLocalEnvironment.MQ.GET. as the correlation name for all fields that relate to the MQGet node.

You can set the following properties under the OutputLocalEnvironment.MQ.GET tree. If you have set a value for the Input MQ parameters location property on the MQGet node, that tree location is checked instead.

Setting Description
QueueName This setting overrides the MQGet node Queue name property; for example: 
SET OutputLocalEnvironment.MQ.GET.QueueName = 'myQueue';
InitialBufferSize This setting overrides the MQGet node Minimum message buffer size property; for example: 
SET OutputLocalEnvironment.MQ.GET.InitialBufferSize = 1024;
MQGMO.* This setting overrides the MQGET message options that are used by the MQGet node; for example: 
SET OutputLocalEnvironment.MQ.GET.MQGMO.Options = MQGMO_ACCEPT_TRUNCATED_MSG;
SET OutputLocalEnvironment.MQ.GET.MQGMO.WaitInterval = 10000;
This override is provided for flexibility, but use with caution because the MQGMO is used exactly as specified. Node properties and other local environment overrides are not considered.

For more information about the MQGMO structure, see the IBM® MQ product documentation online.