This is a reusable action for GitHub Actions. This action just runs a single command and captures the outputs. Easy to use and useful to capture multi-line outputs.

The way to capture a command's multi-line standard output / error is not intuitive on GitHub Actions.

• set-output Truncates Multiline Strings - #9 by andreasplesch - GitHub Actions - GitHub Community
• set-env truncates multiline strings · Issue #403 · actions/toolkit · GitHub

Use this action gh640/command-result-action in your workflow with command input.

uses: gh640/command-result-action@v1
with:
  command: npm outdated
id: myaction

You can optionally change the working directory by passing cwd as input:

uses: gh640/command-result-action@v1
with:
  command: npm outdated
  cwd: ./src
id: myaction

You can use the output in subsequent steps. In the above case, the following variables are available:

• ${{ steps.myaction.outputs.exitCode }}
• ${{ steps.myaction.outputs.stdout }}
• ${{ steps.myaction.outputs.stderr }}

This action uses @actions/exec and @actions/core. The behavior of this action is almost same as one of the following action with actions/github-script:

uses: actions/github-script@v6
with:
  script: |
    const result = await exec.getExecOutput('npm outdated', [], {
      ignoreReturnCode: true,
    })
    core.setOutput('exitCode', result.exitCode)
    core.setOutput('stdout', result.stdout)
    core.setOutput('stderr', result.stderr)
id: myaction

• GitHub - gh640/test-command-result-action

No. This action supports only one command.