Argo Events Sensor Fails to Trigger Workflow: 'Unknown Artifact Location' Error

[himanshuchoudhary448]

Describe the bug
When using a minimal webhook configuration, the Argo Events sensor fails to trigger a workflow. The error observed in the sensor logs is: 'Failed to execute a trigger: unknown artifact location {nil nil nil nil nil nil}'. Despite the event being successfully received and processed by the event source and sensor, the workflow is not being created or executed.
This issue seems to occur during the sensor's trigger phase when it attempts to create the workflow. The expected behavior is for the workflow to be created successfully or, if there's a problem, a clear and actionable error message should be logged.

To Reproduce
Steps to reproduce the behavior:

1. Extract the zip file for the project configuration
   argo-config.zip

2. Deploy the Argo Event Source and Sensor configuration files:
   kubectl apply -f webhook.yaml
   kubectl apply -f event-sensor.yaml

3. Trigger the webhook by sending a POST request to the Event Source service
   curl -X POST http://<EVENTSOURCE_SVC_CLUSTER_IP>:12000/trigger -d '{"key":"value"}'
   (Replace <EVENTSOURCE_SVC_CLUSTER_IP> with the Cluster IP from kubectl get svc -n ).

4. Check the logs of the Sensor pod:
   kubectl logs -n -l sensor-name=minimal-webhook-sensor

5. Verify that no workflow is created using:
   kubectl get workflows -n

Expected behavior
The workflow should be successfully created in the configured namespace and run as expected. If there is an issue, the error message should clearly explain the root cause, such as RBAC misconfiguration or invalid parameters.

Screenshots

Environment (please complete the following information):

• Kubernetes: v1.30.7-eks-56e63d8
• Argo: CLI: v2.13.2+cd43214, Server: v2.11.11+9f40df0
• Argo Events: v1.9.2

Additional context
The issue persists even with a minimal webhook and sensor configuration. RBAC permissions have been verified, and the required roles (e.g., operate-workflow-role) include permissions for creating workflows and workflow-related resources. The logs indicate that the event source successfully dispatches the event and the sensor processes it, but the workflow creation fails at the trigger phase with the error: "unknown artifact location." This behavior suggests a potential bug in Argo Events or a misconfiguration not clearly indicated by the logs.

Message from the maintainers:

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