Accessing output parameters from parent tasks inside a sub workflow

[prakashbalaji]

Hello All,

I have a workflow and subworkflow and the definition is highlighted in the below image. I cannot access the http output parameters from the parent tasks inside my subworkflow. In the below example the estimationRequestId and addressToken are always null even though the "estimation_requested" and "start_process" task has output variables populated correctly. Would be great if anyone can give pointers or let me know the issue here. Thanks for the help.

Thanks,
Prakash

[v1r3n]

Can you include the workflow inputs for the sub-workflow and definition of the sub-workflow?

[prakashbalaji]

@v1r3n - Thanks for taking a look at this. The entire workflow definition is below. The issue is with "estimationRequestId" and "addressToken" field being always passed as null in the "estimation_created" sub workflow task.

{
  "name": "Test",
  "description": "Test workflow",
  "version": 17,
  "tasks": [
    {
      "name": "start_process",
      "taskReferenceName": "start_process",
      "type": "SIMPLE",
      "inputParameters": {
        "propertyInstanceId": "${workflow.input.propertyInstanceId}",
        "customerId": "${workflow.input.customerId}",
        "addressToken": "${workflow.input.addressToken}"
      }
    },
    {
      "name": "estimation_requested",
      "taskReferenceName": "estimation_requested",
      "type": "HTTP",
      "inputParameters": {
        "http_request": {
          "uri": "http://localhost:3000/estimation_requested",
          "method": "GET",
          "accept": "application/json",
          "connectionTimeOut": 0,
          "readTimeOut": 0
        }
      }
    },
    {
      "name": "esitmation_workflow",
      "taskReferenceName": "esitmation_workflow",
      "type": "SUB_WORKFLOW",
      "subWorkflowParam": {
        "name": "esitmation_workflow",
        "version": 1,
        "workflowDefinition": {
            "name": "Estimation Workflow",
            "description": "Estimation Workflow",
            "version": 1,
            "tasks": [{
                "name": "estimation_created",
                "taskReferenceName": "estimation_created",
                "type": "HTTP",
                "inputParameters": {
                    "http_request": {
                      "uri": "http://localhost:3000/estimation_created",
                      "method": "GET",
                      "accept": "application/json",
                      "connectionTimeOut": 0,
                      "readTimeOut": 0
                    },
                    "estimationRequestId": "${estimation_requested.output.response.body.estimationRequestId}",
                    "addressToken": "${start_process.output.addressToken}"
                }
            },
            {
              "name": "estimation_in_progress",
              "taskReferenceName": "estimation_in_progress",
              "type": "HTTP",
              "inputParameters": {
                  "http_request": {
                    "uri": "http://localhost:3000/estimation_in_progress",
                    "method": "GET",
                    "accept": "application/json",
                    "connectionTimeOut": 0,
                    "readTimeOut": 0
                  },
                  "estimationRequestId": "${estimation_created.output.response.body.estimationRequestId}"
              }
              },
              {
                "name": "estimation_completed",
                "taskReferenceName": "estimation_completed",
                "type": "HTTP",
                "inputParameters": {
                    "http_request": {
                      "uri": "http://localhost:3000/estimation_completed",
                      "method": "GET",
                      "accept": "application/json",
                      "connectionTimeOut": 0,
                      "readTimeOut": 0
                    },
                    "estimationRequestId": "${estimation_requested.output.estimationRequestId}"
                }
              }
            ],
            "outputParameters": {
                "underwritingResponseId": "${estimation_completed.output.underwritingResponseId}"
            },
            "restartable": true,
            "workflowStatusListenerEnabled": true,
            "schemaVersion": 2
        }
    }
    },
    {
      "name": "wait_for_assessment_completion",
      "taskReferenceName": "wait_for_assessment_completion",
      "type": "HTTP",
      "inputParameters": {
        "http_request": {
          "uri": "http://localhost:3000/wait_for_assessment_completion",
          "method": "GET",
          "accept": "application/json",
          "connectionTimeOut": 0,
          "readTimeOut": 0
        }
      }
    },
    {
      "name": "process_offers",
      "taskReferenceName": "process_offers",
      "type": "HTTP",
      "inputParameters": {
        "http_request": {
          "uri": "http://localhost:3000/process_offers",
          "method": "GET",
          "accept": "application/json",
          "connectionTimeOut": 0,
          "readTimeOut": 0
        }
      }
    }
  ],
  "outputParameters": {
    "estimationRequestId": "${estimation_requested.output.estimationRequestId}"
  },
  "restartable": true,
  "workflowStatusListenerEnabled": true,
  "schemaVersion": 2, 
  "ownerEmail": "[email protected]"
}

[v1r3n]

sub workflows are executed as an independent workflows, so they cannot access the inputs from the "parent" workflow tasks.
Any inputs that sub workflow needs should be passed as inputs to the sub workflow task and you can then access them as workflow.input.<parametername> in the sub workflow definiton.

e.g. In your subworkflow definition you should include the following input parameter block if you need these two parameters to be used in the sub workflow:

"inputParameters": {
        "estimationRequestId": "${estimation_requested.output.estimationRequestId}",
        "addressToken": "${start_process.output.addressToken}"
      },

And in one of the task where you plan to use the sub workflow, use it as:

{
              "name": "estimation_created",
              "taskReferenceName": "estimation_created",
              "inputParameters": {
                "estimationRequestId": "${workflow.input.estimationRequestId}",
                "addressToken": "${workflow.input.addressToken}"
              },
             ...
            }

[prakashbalaji]

@v1r3n - Thanks for adding the required clarity. I will try the suggested approach and update this thread. Appreciate your help here.

[prakashbalaji]

@v1r3n - This worked perfectly.