action.yml

name: "URL Wathcer"
description: "URL Wathcer with Composite actions"
inputs:
  url:
    description: "URL to watch"
    required: true
  excluded-patterns:
    description: |
      Excluded patterns to check.
      * Extended regular expression of sed.
      * Each patterns are separated by ';'
      * Example: '"style.min.css\?[0-9]*-[0-9]*";"common.js\?[0-9]*-[0-9]*"'
    required: false
    default: ""
  save-dir:
    description: "Directory to save the latest file."
    required: false
    default: ./output
  save-file:
    description: "The name of the latest file."
    required: false
    default: latest.txt
outputs:
  diff:
    description: |
      Whether the URL(HTML contents) is updated or not.
      * true: updated
      * false: NOT updated
    value: ${{ steps.diff-check.outputs.diff }}
runs:
  using: "composite"
  steps:
    - name: Validate inputs
      shell: bash
      run: |
        if [ -z ${{ inputs.url }} ]; then
          echo "inputs.url should not be empty"
          exit 1
        fi
        if [ -z ${{ inputs.save-dir }} ]; then
          echo "inputs.save-dir should not be empty"
          exit 1
        fi
        if [ -z ${{ inputs.save-file }} ]; then
          echo "inputs.save-file should not be empty"
          exit 1
        fi
    - name: Setup
      shell: bash
      run: |
        mkdir -p ${{ inputs.save-dir }}
        # When first executed, the output file does not exist..
        if [[ ! -f "${{ inputs.save-dir }}/${{ inputs.save-file }}" ]]; then
          echo "Target file does not exist, so create a empty file."
          touch "${{ inputs.save-dir }}/${{ inputs.save-file }}"
        fi
    - name: Diff check
      id: diff-check
      working-directory: ${{ inputs.save-dir }}
      shell: bash
      run: |
        curl ${{ inputs.url }} > "${{ inputs.save-file }}_now"

        # save the current field separator to restore lator
        old_IFS=$IFS
        # new field separator
        IFS=";"
        excluded_patterns="${{ inputs.excluded-patterns }}"
        read -ra excluded_patterns_array <<< "$excluded_patterns"
        IFS=$old_IFS

        for pattern in "${excluded_patterns_array[@]}"; do
          echo "$pattern"
          # Delete the specified pattern
          sed -i -E "s@$pattern@@g" "${{ inputs.save-file }}_now"
          sed -i -E "s@$pattern@@g" "${{ inputs.save-file }}"
        done

        # diff check
        set +e
        diff "${{ inputs.save-file }}_now" "${{ inputs.save-file }}"
        STATUS_CODE=$?
        set -e

        result=false
        if [ "${STATUS_CODE}" -gt 0 ]; then
          result=true
        fi
        echo "::set-output name=diff::${result}"
    - name: Commit the change and push it when diff found
      if: ${{ steps.diff-check.outputs.diff == 'true' }}
      shell: bash
      working-directory: ${{ inputs.save-dir }}
      run: |
        mv "${{ inputs.save-file }}_now" "${{ inputs.save-file }}"

        git config user.name "github-actions[bot]"
        git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
        git add "${{ inputs.save-file }}"
        git commit -m "Updated latest file."
        git push
branding:
  icon: "globe"
  color: "orange"