action.yml

name: 'check-command-output-diff'
description: 'Run command and check diff between old output of the command and new one.'
inputs:
  command:
    description: 'Command to run.'
    required: true
  command_output:
    description: 'Path of the command output file.'
    required: true
  cache_key_prefix:
    description: 'Key prefix for cache of the command output file.'
    required: true
outputs:
  is_same:
    description: "If old and new output is same, true."
    value: ${{ steps.compare.outputs.is_same }}
runs:
  using: "composite"
  steps:
    - name: Get Date
      id: get_date
      run: |
        echo "::set-output name=date::$(/bin/date -u "+%Y-%m-%d-%H_%M_%S")"
      shell: bash
    - name: Make temp file
      id: mktemp
      run: |
        echo "::set-output name=tempfile::$(mktemp)"
      shell: bash
    - name: Cache
      uses: actions/cache@v2
      with:
        path: ${{ inputs.command_output }}
        key: ${{ inputs.cache_key_prefix }}-${{ steps.get_date.outputs.date }}
        restore-keys: ${{ inputs.cache_key_prefix }}-
    - name: Run command
      shell: bash
      run: |
        ${{ inputs.command }} > ${{ steps.mktemp.outputs.tempfile }}
    - name: Compare
      id: compare
      shell: bash
      run: |
        diff ${{ inputs.command_output }} ${{ steps.mktemp.outputs.tempfile }} && echo "::set-output name=is_same::true" || echo "::set-output name=is_same::false"
        mv ${{ steps.mktemp.outputs.tempfile }} ${{ inputs.command_output }}
        cat ${{ inputs.command_output }}