Azure Logic App with trigger from Event Hubs but not triggered when there is event

Question

I'm working on a logic app where the trigger is when events are available in Event Hub. I have confirmed that I have sent events to the Event Hub by checking the metrics from the portal under the specific Event Hub Instance. However, the logic app doesn't get triggered even when event has been sent. There is no record error or warning so I don't know where else to check.

I followed this https://learn.microsoft.com/en-us/azure/connectors/connectors-create-api-azure-event-hubs regarding permission and connection string.

Would you know what else I am missing or anything else I should check? Do I need an event subscription?

Answer 1

Hi @Rachel I

Just went through this again to confirm my findings:

On your post you mentioned this tutorial: https://learn.microsoft.com/en-us/azure/connectors/connectors-create-api-azure-event-hubs

if you check that tutorial, the trigger screen shot is what you get on a "consumption" logic app (Documentation don't mention but you can check when creating one of each type.) : https://learn.microsoft.com/en-us/azure/connectors/connectors-create-api-azure-event-hubs#add-event-hubs-trigger

The "Standard" version is a bit different and more limited:

I have managed to get this working in portal with both the namespace connection and the hub connection. But I have had some trouble doing the whole process using VS Code.

Another important detail, the workflow must be stateful (I believe this is so when the trigger pull the event, it can set the checkpoint). if you try to add the trigger to a stateless Workflow though VS code you may not see this error:

In VS Code I created as "stateless" and managed to deploy without errors. What is different from portal:

but it does not run:

After that I created a stateful in VS code and redeployed:

it run as expected:

look like depending on the sequence of actions during development/design, some actions are not validated like when doing direct in the portal. like adding an event hub trigger to a stateless flow. that should inform the invalid action but won't happen in VS code

2 suggestions:

1. Make sure your workflow is stateful
2. Try to check with an azure administrator with access to the portal if the workflow has been deployed as expected

Case that information helps, don't forget to vote or mark as Answer to help the community. Cheers!