action.yml

name: 'Markdown Summary Template'
description: 'Add custom step summaries to your workflows with ease. No more 200 lines of "echo ... >> $GITHUB_STEP_SUMMARY"'
branding:
  icon: align-center
  color: gray-dark
inputs:
  template:
    required: true
    description: | 
      Your markdown template. Write as if it was normal markdown.
      For JetBrains users, add `# language="markdown"` to the line above to get nice syntax highlighting.
  step-output-only:
    default: 'false'
    description: |
      Whether to only emit the template to GitHub step output instead of adding it directly to the step summary
      Useful if you want to feed the template into some other workflow step.
  variables:
    required: false
    description: |
      A list of environment variables to inject into your markdown template.
      For example;
        ...
        variables: >-
          FOO="bar"
          SOMEONE="world"
        template: |
          # Hello, $SOMEONE
          This is $FOO
outputs:
  parsed:
    value: ${{ steps.template.outputs.parsed }}
    description: |
      Parsed output of your template.
      Useful if you want to feed the template into some other workflow step.

  input:
    value: ${{ steps.template.outputs.input }}
    description: |
      Your raw template before it was parsed.

  variables:
    value: ${{ steps.template.outputs.variables }}
    description: |
      The input variables you provided to build the template. Handy if you need to re-use them somewhere else.
runs:
  using: "composite"
  steps:
    - name: 'Build template'
      id: template
      shell: bash
      env:
        TEMPLATE: ${{ inputs.template }}
        STEP_OUTPUT_ONLY: ${{ inputs.step-output-only }}
      # language="bashpro shell script"
      run: |
        parsed_template="$(echo "$TEMPLATE" | ${{ inputs.variables }} envsubst)"
        
        emitToOutput() {
            local key="$1"
            local value="$2"
            local EOF="EOF-$key-$RANDOM"
          
            # https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#multiline-strings
            echo "$key<<$EOF"   >> $GITHUB_OUTPUT
            echo "$value"       >> $GITHUB_OUTPUT
            echo "$EOF"         >> $GITHUB_OUTPUT
          }
        
        if [[ "$STEP_OUTPUT_ONLY" != "true"  ]]; then
          echo "$parsed_template" >> $GITHUB_STEP_SUMMARY || exit 1
        fi
        
        emitToOutput parsed "$parsed_template"            || exit 1
        emitToOutput input "$TEMPLATE"                    || exit 1
        emitToOutput variables "${{ inputs.variables }}"  || exit 1