Github Actions - multiline output from a step, with GITHUB_OUTPUT

multiline Github Actions output.md

This is explained in the Github Actions docs, but is not explicitly clear : https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#setting-an-output-parameter

It is explained in this issue : github/docs#21529

Here is my example :

runs:
  using: "composite"
  steps:
    - name: Run command
      id: command
      shell: bash
      run: |
        res=$( ls -al )

        echo "myresult<<EOF" >> "$GITHUB_OUTPUT"
        echo $res >> "$GITHUB_OUTPUT"
        echo "EOF" >> "$GITHUB_OUTPUT"

    - name: DEBUG
      if: ${{ always() }}
      run: |
        echo "result = ${{ steps.command.outputs.myresult }}"

In this example :

• the result of ls is stored in the res variable
• this value is echoed out into GITHUB_OUTPUT over several lines
• the first line holds the name of the output variable myresult
• the output is available in the myresult output of the command step
• the output is on one single line, so that is easy to use if it is JSON, for example