Pub / Sub

Publish data to be consumed by a pub/sub trigger

The Pub/sub connector works in conjunction with the Pub/sub trigger.

They serve the following purposes:

• The Pub/sub connector can be used to publish information to any specific topic
• The Pub/sub trigger can be used to subscribe to any specific topic From an architectural point of view this can be very powerful. Rather than placing the responsibility on one source workflow to distribute information to other workflows (as per callable workflows) the source workflow can focus on simply gathering and publishing content. Any subscriber workflows can then be set up as and when they are needed. This allows for a more flexible 'ad-hoc' approach, but it will not be suitable for the specific data processing use cases outlined in the above callable workflows page - where you want the source workflow to have tight control and visibility over where data is being sent and for what purpose.

Authentication

Any workflows that wish to connect and share content via pub/sub must use the same pub/sub authentication. You can create an auth when you add either a pub/sub connector or trigger to a workflow.

Or you can go to the 'Authentications' section of your dashboard and click 'Create new authentication': You can then give a name to your auth which will help identify what category of topics it will be publishing to: In the final screen then create a password:

How to publish and subscribe

To **publish **you must add a Pub/sub connector to your workflow Then you need to set:

• The 'Workspace' to publish to ('Organization' or 'Same workspace')
• The arbitrary 'Topic name'
• The 'Data' that is being published Any subscribing workflow needs to choose the Pub/sub trigger upon creation: Then you need to set:
• The 'Workspace' ('Organization' or 'Same workspace')
• The arbitrary **'Topic name' **being subscribed to

Example usage

The following example imagines a scenario whereby one source workflow is gathering and publishing information about new leads, and two other workflows are subscribing to this information.

Publishing workflow setup

The publishing workflow is using a webhook trigger which is receiving leads from an imaginary source in the following format:

{
	"lead": \{
		"lastName": "Penelope",
		"firstName": "Pitstop",
		"email": "penelope.pitstop@acme.co"
	\}
}

When publishing data you must specify the following:

• The 'Workspace' to publish to ('Organization' or 'Same workspace')
• The arbitrary 'Topic name'
• The 'Data' that is being published In this case by using $.steps.trigger.body we are dynamically picking up the data each time it comes through from the webhook trigger and publishing it as a simple json payload:

Subscribing workflow 1 setup

In a subscriber workflow all we have to do is set the 'Worskpace' and 'Topic name': And as you can see from the logs, the trigger output will contain the topic content within a 'data' json payload: In this case we are grabbing the details of the new lead and sending a notification to Slack:

Subscribing workflow 2 setup

The second subscribing workflow is set up in exactly the same way, but the data is instead sent to a Google Sheet: