OpenShift resources such as KN Service, Service, Ingress, Deployment, Pods, and so on (see: https://github.com/knative/specs/blob/main/specs/eventing/overview.md#addressable) can be called by a regular HTTP POST request.

This means that SW could support this feature out of the box, not needing an OpenAPI interface to do so.

Image this example:

{
  "id": "myworkflow",
  "specVersion": "0.8",
  "version": "1.0",
  "start": "State1",
  "functions": [
    {
      "name": "function1",
      "type": "custom",
      "operation": "openshift:serving.knative.dev/v1/mynamespace/myservice",
      "metadata": {
        "path": "/my_path"
      }
    }
  ],
  "states": [
    {
      "name": "State1",
      "type": "operation",
      "actions": [
        {
          "functionRef": {
            "refName": "function1",
            "arguments": {
              "data": "${ .data }"
            }
          }
        }
      ],
      "end": true
    }
  ]
}

The engine would make POST requests to these endpoints with the given payload manipulated by the workflow. For example:

openshift:serving.knative.dev/v1/mynamespace/myservice -> the explicitly openshift resource at mynamespace

This will make the integration with the platform way easier and enhance the dev experience.

This feature should be implemented based on https://issues.redhat.com/browse/KOGITO-8430.