GitHub Actions - how to run parallel tests in RSpec for Ruby on Rails project. See article how to run RSpec on GitHub Actions for Ruby on Rails app using parallel jobs https://docs.knapsackpro.com/2019/how-to-run-rspec-on-github-actions-for-ruby-on-rails-app-using-parallel-jobs or sign up at https://knapsackpro.com/?utm_source=github&utm_medium=…

main.yaml

# .github/workflows/main.yaml
name: Main

on: [push]

jobs:
  test:
    runs-on: ubuntu-latest

    # If you need DB like PostgreSQL, Redis then define service below.
    # https://github.com/actions/example-services/tree/master/.github/workflows
    services:
      postgres:
        image: postgres:10.8
        env:
          POSTGRES_USER: postgres
          POSTGRES_PASSWORD: ""
          POSTGRES_DB: postgres
        ports:
          - 5432:5432
        # needed because the postgres container does not provide a healthcheck
        # tmpfs makes DB faster by using RAM
        options: >-
          --mount type=tmpfs,destination=/var/lib/postgresql/data
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5

      redis:
        image: redis
        ports:
          - 6379:6379
        options: --entrypoint redis-server

    # https://help.github.com/en/articles/workflow-syntax-for-github-actions#jobsjob_idstrategymatrix
    strategy:
      fail-fast: false
      matrix:
        # [n] - where the n is a number of parallel jobs you want to run your tests on.
        # Use a higher number if you have slow tests to split them between more parallel jobs.
        # Remember to update the value of the `ci_node_index` below to (0..n-1).
        ci_node_total: [2]
        # Indexes for parallel jobs (starting from zero).
        # E.g. use [0, 1] for 2 parallel jobs, [0, 1, 2] for 3 parallel jobs, etc.
        ci_node_index: [0, 1]

    env:
      RAILS_ENV: test
      GEMFILE_RUBY_VERSION: 2.7.2
      PGHOST: localhost
      PGUSER: postgres
      # Rails verifies the time zone in DB is the same as the time zone of the Rails app
      TZ: "Europe/Warsaw"

    steps:
      - uses: actions/checkout@v2

      - name: Set up Ruby
        uses: ruby/setup-ruby@v1
        with:
          # Not needed with a .ruby-version file
          ruby-version: 2.7
          # runs 'bundle install' and caches installed gems automatically
          bundler-cache: true

      - name: Create DB
        run: |
          bin/rails db:prepare

      - name: Run tests
        env:
          KNAPSACK_PRO_TEST_SUITE_TOKEN_RSPEC: ${{ secrets.KNAPSACK_PRO_TEST_SUITE_TOKEN_RSPEC }}
          KNAPSACK_PRO_TEST_SUITE_TOKEN_CUCUMBER: ${{ secrets.KNAPSACK_PRO_TEST_SUITE_TOKEN_CUCUMBER }}
          KNAPSACK_PRO_TEST_SUITE_TOKEN_MINITEST: ${{ secrets.KNAPSACK_PRO_TEST_SUITE_TOKEN_MINITEST }}
          KNAPSACK_PRO_TEST_SUITE_TEST_UNIT: ${{ secrets.KNAPSACK_PRO_TEST_SUITE_TOKEN_TEST_UNIT }}
          KNAPSACK_PRO_TEST_SUITE_TOKEN_SPINACH: ${{ secrets.KNAPSACK_PRO_TEST_SUITE_TOKEN_SPINACH }}
          KNAPSACK_PRO_CI_NODE_TOTAL: ${{ matrix.ci_node_total }}
          KNAPSACK_PRO_CI_NODE_INDEX: ${{ matrix.ci_node_index }}
          KNAPSACK_PRO_LOG_LEVEL: info
          # if you use Knapsack Pro Queue Mode you must set below env variable
          # to be able to retry CI build and run previously recorded tests
          # https://github.com/KnapsackPro/knapsack_pro-ruby#knapsack_pro_fixed_queue_split-remember-queue-split-on-retry-ci-node
          KNAPSACK_PRO_FIXED_QUEUE_SPLIT: true
          # RSpec split test files by test examples feature - it's optional
          # https://knapsackpro.com/faq/question/how-to-split-slow-rspec-test-files-by-test-examples-by-individual-it
          # KNAPSACK_PRO_RSPEC_SPLIT_BY_TEST_EXAMPLES: true
        run: |
          # run tests in Knapsack Pro Regular Mode
          bundle exec rake knapsack_pro:rspec
          bundle exec rake knapsack_pro:cucumber
          bundle exec rake knapsack_pro:minitest
          bundle exec rake knapsack_pro:test_unit
          bundle exec rake knapsack_pro:spinach
          # you can use Knapsack Pro in Queue Mode once recorded first CI build with Regular Mode
          bundle exec rake knapsack_pro:queue:rspec
          bundle exec rake knapsack_pro:queue:cucumber
          bundle exec rake knapsack_pro:queue:minitest

Thanks for this :-)

You're welcome @b-murphy. You can learn more about running faster parallel tests from this article https://docs.knapsackpro.com/2020/how-to-speed-up-ruby-and-javascript-tests-with-ci-parallelisation