protobuf.yml

name: protobuf

on:
  pull_request:
  # NOTE: don't run this on "workflow_dispatch" or "schedule" as it will commit
  # directly to the branch

jobs:
  protobuf:
    runs-on: ubuntu-latest
    timeout-minutes: 10

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Install Protobuf
        uses: mamba-org/setup-micromamba@v1
        with:
          environment-name: protobuf
          create-args: protobuf
          init-shell: bash

      - name: Install Bufbuild
        run: |
          # activate homebrew (NOTE: must use "shell: bash -el {0}" to use this)
          eval "$(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"  # activate homebrew

          # NOTE: bufbuild does exist on conda-forge but hasn't been updated for a while
          brew install bufbuild/buf/buf

      - name: Lint
        run: |
          # lint .proto files
          eval "$(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"  # activate homebrew
          cd proto
          buf lint

      - name: Compatibility
        shell: bash -el {0}
        run: |
          eval "$(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"  # activate homebrew
          cd proto
          # NOTE: "buf breaking" exits "100" for a missing file (i.e. new version not present on old branch)
            # --against 'https://github.com/cylc/cylc-flow.git#tag=${{ github.base_ref }},subdir=proto') \
          buf breaking \
            --against 'https://github.com/oliver-sanders/cylc-flow.git#tag=${{ github.base_ref }},subdir=proto' \
            || ( \
              ret=$?; \
              if [[ $ret == 100 ]]; then exit 0; \
              elif [[ $ret != 0 ]]; then echo '::error:: Breaking changes detected, create a new version of the protobuf schema if this is desired and increment the Cylc API number to match'; \
              fi \
            )

      - name: Build
        shell: bash -el {0}
        run: |
          # generate .py and .pyi files from the .proto files
          eval "$(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"  # activate homebrew
          micromamba activate protobuf
          cd proto
          buf generate

      - name: Configure git
        uses: cylc/release-actions/configure-git@v1

      - name: Commit & Push
        run: |
          if [[ -z $(git diff --stat) ]]; then
            echo '::error:: No functional changes made to the protobuf schema'
            exit 0
          else
            echo '::info:: pushing update commit'
              git add -u
              git commit -m 'protobuf: updating generated files'
              git push origin HEAD:${{ github.head_ref }}
            exit 0
          fi