Unable to Subscribe to EventGrid Domain using Java Function App Event grid Trigger function

Question

I am trying to subscribe a function in an isolated function app to an event grid domain and am receiving the following error:

{\"status\":\"Failed\",\"error\":{\"code\":\"ResourceOperationFailure\",\"message\":\"The resource operation completed with terminal provisioning state 'Failed'.\",\"details\":[{\"code\":\"Endpoint validation\",\"message\":\"Destination endpoint not found. Resource details: resourceId: /subscriptions/xxx/resourceGroups/xxx/providers/Microsoft.Web/sites/xxx/functions/event-subscriber. Resource should pre-exist before attempting this operation. Activity id:c1d3c2a0-eb71-445f-aa63-af46609980b9, timestamp: 6/15/2023 10:56:47 PM (UTC).\"}]}}

This error is occurring both when trying to add the subscription using Teraform as well as via the Azure web portal.

I have verified that the function app is running and that the function is visible.

Any help would be appreciated.

Answer 1

Ray, Tapan Thanks for posting your question in Microsoft Q&A. I assume you created Azure Event Grid trigger in Azure Functions and when creating an event subscription to Azure Functions failed with the above error (endpoint Type as Azure Function like below).

I quickly looked at the activity ID c1d3c2a0-eb71-445f-aa63-af46609980b9 and found that it was trying to connect webhook endpoint https://{funcapp-name}.azurewebsites.net/runtime/webhooks/eventgrid and failed with 400 bad request since it was unable to connect. I suggest you validate the endpoint URL correctly passed in Terraform or via portal as per doc: Webhook endpoint URL like eventgrid?functionName={functionname}&code={systemkey} and also make sure it is accessible from event grid (outside the portal). Also, check if the function parameters are configured correctly as described in Examples.

If you still face the issue, please reach out to azure support team for further assistance. They have the best tools to review the backend logs and find the cause. I hope this helps and let me know if any questions.

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