GitHub actions to test an Elixir Phoenix application and deploy to Gigalixir

github-elixir-deploy.yml

name: CI/CD

on:
  push:
    branches: [ main ]
  pull_request:
    branches: [ main ]

env:
  MIX_ENV: test

jobs:
  test:
    runs-on: ubuntu-latest

    services:
      db:
        image: postgres:12
        env:
          POSTGRES_USER: postgres
          POSTGRES_PASSWORD: postgres
          POSTGRES_DB: quark_test
        ports: ['5432:5432']
        options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5


    steps:
    - uses: actions/checkout@v2
    - name: Setup elixir
      uses: erlef/setup-beam@v1
      with:
        elixir-version: 1.12.1
        otp-version: 24.0.2

    - name: Setup node
      uses: actions/setup-node@v1
      with:
        node-version: 14.17.1

    - name: Retrieve mix dependencies cache
      uses: actions/cache@v1
      id: mix-cache # id to use in retrieve action
      with:
        path: deps
        key: ${{ runner.os }}-mix-${{ hashFiles(format('{0}{1}', github.workspace, '/mix.lock')) }}

    - name: Install mix dependencies
      if: steps.mix-cache.outputs.cache-hit != 'true'
      run: |
        mix local.rebar --force
        mix local.hex --force
        mix deps.get

    - name: Retrieve npm dependencies cache
      uses: actions/cache@v2
      id: npm-cache # id to use in retrieve action
      with:
        path: ~/.npm
        key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
        restore-keys: |
          ${{ runner.os }}-node-

    - name: Install npm dependencies
      if: steps.npm-cache.outputs.cache-hit != 'true'
      run: (cd assets && npm install)

    - name: Test
      run: |
        mix format --check-formatted
        mix credo
        mix test

  deploy:
    needs: test

    # only run this job if the workflow is running on the main branch
    if: github.ref == 'refs/heads/main'

    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2
        
        # actions/checkout@v2 only checks out the latest commit,
        # so we need to tell it to check out the entire main branch
        with:
          ref: main
          fetch-depth: 0

      # configure the gigalixir-actions with our credentials and app name
      - uses: mhanberg/gigalixir-action@v0.1.0
        with:
          GIGALIXIR_USERNAME: ${{ secrets.GIGALIXIR_USERNAME }}
          GIGALIXIR_PASSWORD: ${{ secrets.GIGALIXIR_PASSWORD }}
          GIGALIXIR_APP: <my-app>
          SSH_PRIVATE_KEY: ${{ secrets.SSH_PRIVATE_KEY }}