One limitation of Eventarc is that it currently only supports Cloud Run as targets. This will change in the future with more supported event targets. It’d be nice to have a future Eventarc trigger to route events from different sources to Workflows directly.
In absence of such a Workflows enabled trigger today, you need to do a little bit of work to connect Eventarc to Workflows. Specifically, you need to use a Cloud Run service as a proxy in the middle to execute the workflow.
Let’s take a look at a couple of concrete examples.
Eventarc Pub/Sub + Workflows integration
In the first example, imagine you want a Pub/Sub message to trigger a workflow.
Define and deploy a workflow
First, define a workflow that you want to execute. Here’s a sample workflows.yaml that simply decodes and logs the Pub/Sub message body: