Usage of Outputs.Parameters in Http Template

[anvmga]

Trying to pass output of a step to another step input using outputs.parameters, however, the workflow is returning the literal text instead of actual value.

Result from the logs

http-output-parameters-fbmcb-print-message-2963366455: Received message: {{steps.get.outputs.parameters.result}}
http-output-parameters-fbmcb-print-message-2963366455: URL: {{steps.get.outputs.parameters.url}}

Workflow used

apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: http-output-parameters-
spec:
  entrypoint: main
  templates:
  - name: main
    steps:
    - - name: get
        template: http-get

    - - name: print
        template: print-message
        arguments:
          parameters:
          - name: message
            value: "{{steps.get.outputs.parameters.result}}"
          - name: url
            value: "{{steps.get.outputs.parameters.url}}"

  - name: http-get
    http:
      url: https://httpbin.org/get
    outputs:
      parameters:
      - name: result
        valueFrom:
          jsonPath: '{.origin}'
      - name: url
        value: "https://httpbin.org/get"

  - name: print-message
    inputs:
      parameters:
      - name: message
      - name: url
    script:
      image: alpine:3.7
      command: [sh, -c]
      source: |
        echo "Received message: {{inputs.parameters.message}}"
        echo "URL: {{inputs.parameters.url}}"

Output parameter doc doesn't have details about the same. Can somebody help to find out what could be the issue with the template?

[MasonM]

It looks like there's a bug with HTTP templates where the outputs: always get overridden with result, but you can workaround that by extracting the data from result:

apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: http-output-parameters-
spec:
  entrypoint: main
  templates:
  - name: main
    steps:
    - - name: get
        template: http-get

    - - name: print
        template: print-message
        arguments:
          parameters:
          - name: message
            value: "{{=jsonpath(steps.get.outputs.result, '$.origin')}}"
          - name: url
            value: "{{=jsonpath(steps.get.outputs.result, '$.url')}}"

  - name: http-get
    http:
      url: https://httpbin.org/get

  - name: print-message
    inputs:
      parameters:
      - name: message
      - name: url
    script:
      image: alpine:3.7
      command: [sh, -c]
      source: |
        echo "Received message: {{inputs.parameters.message}}"
        echo "URL: {{inputs.parameters.url}}"

[anvmga]

Thanks @MasonM for the quick help. Tried the solution and its working as expected. Could you let me know what all data will be available as part of output.results? Also is there a detailed documentation regarding the output parameters and its supported options like jsonPath, parameters & ConfigMap refs and all?

Regarding the Bug, will it be fixed in next release?

[MasonM]

Could you let me know what all data will be available as part of output.results?

The response body of the request, as a string. I entered #13953 to clarify this.

Also is there a detailed documentation regarding the output parameters and its supported options like jsonPath, parameters & ConfigMap refs and all?

There's some docs at https://argo-workflows.readthedocs.io/en/stable/walk-through/output-parameters/#result-output-parameter and https://argo-workflows.readthedocs.io/en/latest/fields/#outputs, but they don't mention HTTP templates. #13953 will fix that.

Regarding the Bug, will it be fixed in next release?

Unlikely, since it doesn't look like there's an issue for it yet. Feel free to create one: https://github.com/argoproj/argo-workflows/issues/new?assignees=&labels=type%2Fbug&projects=&template=bug_report.yaml

[anvmga]

Thanks @MasonM for the clarification. Will create the bug.

[anvmga]

Raised Bug #13955