IBM MQ(4.0)
This section describes the IBM MQ agent and IBM MQ APL commands. The agent is a collection agent for real-time workflow configurations.
The IBM MQ Collection acts as a client to an IBM MQ Queue Manager. It collects messages from a defined number of message queues, topics and durable subscriptions, and routes the data as UDRs to a real-time workflow.
Prerequisites
The reader of this information should be familiar with IBM MQ, see https://www.ibm.com/products/mq.
IBM MQ Overview
Connection
At startup, a connection towards an Queue Manager is set up to listen to a number of queues, topics or durable subscriptions. This can be configured either directly in the IBM MQ Collection agent or be dynamically set within an Analysis agent.
If the agent will fail to connect to all configured queues, topics or durable subscriptions, an exception will be written to the system log.
Message Queues
Message queues are used for storing messages in MQ Server. The messages consist of two parts; the binary data used by the application and the delivery information handled by the Queue Manager. The Queue Manager provides a logical container for message queues and is responsible for transferring the data between local and remote queues.
The IBM MQ agent will read the messages in the configured local message queues and each message data will be transferred as a UDR in to the workflow. Depending on the agent's configuration the Queue Manager will remove the message from the queue directly or it will wait until it has been processed.
New messages can also be sent to the Queue Manager with the IBM MQ APL commands.
Topics and Durable Subscriptions
As opposed to the point-to-point communication, IBM MQ offers the possibility to publish and subscribe to topics. Neither the publisher or the subscriber need to know where the other part is located. All interaction between publishers and subscribers are controlled by the Queue Manager.
The IBM MQ agent acts as a subscriber and will register which topics or durable subscriptions to listen for at the Queue Manager. The Queue Manager will then examine every incoming publication and place matching messages on the subscribers queue, which will be read by the IBM MQ agent and transferred as UDRs into the workflow.
The section contains the following subsections: