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Messagebus Queue

Messagebus queue mechanism complements the workflows in a way that any asynchronous computation can be offloaded to another workflow or workflow-extendable process. More info on the described topics can be found at Workflows, Integration Gateway Route Profiler and the Messagebus subsystem.

In this example we will:
  • create a queue

  • create an endpoint

  • write to queue via workflow

  • read from queue via workflow

    • send a payload to an endpoint

  • view endpoint payload in profiler

Create a new Queue

The Consumer here should be Eventbus, since this is how the internal mechanism provides the payload data to the {PRODUCT_NAME} subsystems, including Workflows.

queue create
Figure 1. The screenshot shows the creation of the queue in UI.

Write to Queue

This is a workflow we will use just to manually trigger the write to queue.

You can either use any of the automation buttons to trigger this workflow from the UI. Usually the case would be after creating a record and then sending the new recordID to the queue.

The payload is defined as an Array that is then stringified

  {"key":"foo", "value": "bar"},
  {"key":"bar", "value": "baz"}
queue wf add
Figure 2. A screenshot of the add to queue workflow.

The source code for the workflow example.

Read from Queue

Here we parse the queue payload and create a custom HTTP request to an outside, ie. Kafka (in our example an endpoint we will create for this purpose only).

queue wf read
Figure 3. An example of reading the data from queue.

The source code for the workflow example.

Create a mock service endpoint

What we need now is to trigger the Queue Write workflow and a request will be sent to our local server on the /api/gateway/example_kafka endpoint.

The resulting request can be seen on the Integration Gateway profiler (if you have it enabled, see more at Route Profiler).

queue endpoint
Figure 4. Adding a new endpoint to the Integration Gateway.

Preview the request in the Profiler

This preview is for example only, a way to use the profiler to debug any sending payloads to production / external services.

queue profiler 1
Figure 5. Preview the request headers and other metadata.
queue profiler 2
Figure 6. Preview the request payload.