Optimize PNGs using GitHub actions

README.md

A GitHub action to optimize PNG files that were created/modified in a pull request.

optimize-pngs.yml

name: Optimize PNGs

on:
  pull_request:
    branches:
      - main
jobs:
  format:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
        with:
          ref: ${{ github.head_ref }}
      - name: Optimize PNGs
        env:
          GH_TOKEN: ${{ github.token }}
          PR_NUMBER: ${{ github.event.number }}
        run: |
          PNGS=$(gh pr view $PR_NUMBER --json files --jq '.files.[].path | select(endswith(".png"))')
          if [ -z "$PNGS" ]; then
            echo "No PNGs found"
            exit 0
          fi
          sudo apt-get install -y optipng
          echo $PNGS | xargs optipng -nc -nb -o7
      - name: Commit changes
        uses: stefanzweifel/git-auto-commit-action@v4
        with:
          commit_message: Optimize PNGs
          branch: ${{ github.head_ref }}