EventGrid Trigger - How to set clienttrackingid from triggerbody? - azure-logic-apps

Question

In a microservice environment where requests span multiple services including eventgrid i'd like to configure an end-to-end logging with correlationid.
Inspired by this blog https://toonvanhoutte.wordpress.com/2018/08/05/end-to-end-correlation-across-logic-apps/
How can i configure the EventGrid triggers clientTrackingId with my correlationnr from Events data payload?
Checkout my definition below which does not work.
If i substitute "#{coalesce(json(triggerBody().Data)?.CorrelationNr, guid())}" with a string value or even "#parameters('$connections')['azureeventgrid']['connectionId']" it works like a charm.
"triggers": {
"When_a_resource_event_occurs": {
"correlation": {
"clientTrackingId": "#{coalesce(json(triggerBody().Data)?.CorrelationNr, guid())}"
},
"inputs": {
"body": {
"properties": {
"destination": {
"endpointType": "webhook",
"properties": {
"endpointUrl": "#{listCallbackUrl()}"
}
},
"filter": {
"includedEventTypes": [
"webhook.sp.updated"
]
},
"topic": "/subscriptions/xxxx/resourceGroups/xxx/providers/Microsoft.EventGrid/topics/WebHookManager"
}
},
"host": {
"connection": {
"name": "#parameters('$connections')['azureeventgrid']['connectionId']"
}
},
"path": "/subscriptions/#{encodeURIComponent('xxx')}/providers/#{encodeURIComponent('Microsoft.EventGrid.Topics')}/resource/eventSubscriptions",
"queries": {
"x-ms-api-version": "2017-06-15-preview"
}
},
"splitOn": "#triggerBody()",
"type": "ApiConnectionWebhook"
}
}
Logic App does not trigger. No Error message.

Answer 1

Please check the description about clientTrackingId, and your logic app no runs history is because your triggerBody() doesn't have CorrelationNr with the definition you show.
Actually your Event Grid trigger has detected the event, it just couldn't run with the logic. You could go to the EVALUATION and check the trigger history. It's because the value is null, then it won't run.
If you use HTTP request trigger, you could set the x-my-custom-correlation-id header. or set any key-value in the json body, then set the clientTrackingId with like #{coalesce(json(triggerBody())['keyname'], guid())}.
And if you are using some trigger without header, you have to point the value with string or other parameter like you said the connectionid or the parameter value you custom like below.
So the point is the clientTrackingId must be set before it runs and value could be obatined.