ci.yaml

name: CI

on:
  push:
    branches:
      - main
  pull_request:
    branches:
      - main

jobs:
  # generate the build matrix
  gen_matrix:
    runs-on: ubuntu-latest
    outputs:
      examples_matrix: ${{ steps.gen_matrix.outputs.matrix }}
    steps:
      # checkout the repository
      - uses: actions/checkout@v4

      # generate the build matrix, containing all subdirectories in the 'examples' directory
      # that contain a 'platformio.ini' file
      - name: Generate build matrix
        id: gen_matrix
        run: |
          # Get all subdirectories containing platformio.ini in the ./example directory
          subdirectories=$(find ./examples -type f -name "platformio.ini" -exec dirname {} \; | sort -u)

          # Convert subdirectories to JSON array
          json_array="["
          for subdir in $subdirectories; do
              json_array+="\"$subdir\", "
          done
          json_array="${json_array%, }]"

          echo "$json_array"
          echo "matrix=$json_array" >> $GITHUB_OUTPUT

  # build the CI environment in all examples
  build:
    runs-on: ubuntu-latest
    needs: gen_matrix

    # run all examples in a matrix
    strategy:
      fail-fast: false
      matrix:
        example: ${{ fromJson(needs.gen_matrix.outputs.examples_matrix) }}

    steps:
      # checkout the repository
      - uses: actions/checkout@v4
      
      # enable caching of pip and platformio
      - uses: actions/cache@v4
        with:
          path: |
            ~/.cache/pip
            ~/.platformio/.cache
          key: ${{ runner.os }}-pio
      
      # install python
      - uses: actions/setup-python@v5
        with:
          python-version: '3.9'

      # install platformio
      - name: Install PlatformIO core
        run: pip install --upgrade platformio
      
      # print the platformio.ini file path
      - name: Print matrix value for 'example'
        run: echo ${{ matrix.example }}

      # build the 'CI' environment
      - name: Build 'ci' environment
        run: pio run --project-dir ${{ matrix.example }} --environment ci
  
  # dummy job after all examples were build
  all_build:
    runs-on: ubuntu-latest
    needs: [build]
    if: always()
    steps:
    - name: Decide whether the needed jobs succeeded or failed
      uses: re-actors/alls-green@release/v1
      with:
        jobs: ${{ toJSON(needs) }}