render-manifests.yml

name: Render Manifests
on:
  push:
    branches:
      - main

jobs:
  render-manifests:
    name: Render manifests
    runs-on: ubuntu-latest
    strategy:
      matrix:
        env: [dev, stage, prod]

    steps:
      - uses: actions/checkout@v3
        with:
          # fetch-depth: 0 needed to get all branches
          fetch-depth: 0
      - uses: fregante/setup-git-user@v1
      - 
        name: Render manifests
        run: |
          kustomize build env/${{ matrix.env }} > /tmp/all.yaml
          if ! git checkout env/${{ matrix.env }} -- ; then
            git checkout --orphan env/${{ matrix.env }}
            git rm -rf .
            cp /tmp/all.yaml .
            git add .
            git commit -m "${{ github.event.head_commit.message }}"
            git push --set-upstream origin env/${{ matrix.env }}
          else
            cp /tmp/all.yaml .
          fi 
      -
        name: Deploy to ${{ matrix.env }}
        if: ${{ matrix.env == 'dev' || matrix.env == 'stage' }}
        run: |
          if ! git diff --quiet HEAD ; then 
            git add .
            git commit -m "${{ github.event.head_commit.message }}"
            git push --set-upstream origin env/${{ matrix.env }}
          fi
      -
        name: Deploy PR to ${{ matrix.env }}
        uses: peter-evans/create-pull-request@v4
        if: ${{ matrix.env == 'prod' }}
        with:
          title: ${{ github.event.head_commit.message }}
          commit-message: ${{ github.event.head_commit.message }}
          base: env/${{ matrix.env }}
          branch: deploy-pr/env/${{ matrix.env }}