welcome to this moderated Azure community forum.
if you want to react to certain messages coming from an Event Hub, try the Azure Logic Apps solution.
Logic Apps provides a no-code flow diagram and supports Slack:
Note: you can also use Power Apps if you are knowledgeable about that platform.
You can post messages:
To send these messages, you need to listen for Event Hub messages, using the event hub connector:
I recommend starting with this free MS Learn training about Logic apps.
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