pull_request_ci.yml

# This configures the Continuous Integration builds on every PR, 
# as well as every commit on master.

# This is the name of this workflow
name: CI

# Under what conditions do we run this workflow? Either
# a) It is a commit on a pull request on a branch to be merged into master
# b) It is a push to master (which only happens when we close a pull request)
on:
  pull_request:
    branches: [master]
    types: [opened, synchronize]
  push:
    branches: [master]

# Here is the list of jobs that this workflow will run. There is only one job.
jobs:
  # The name of the job: "build-and-test"
  build-and-test:
    # This specifies the OS that we are running the workflow on: the latest version of Ubuntu
    runs-on: ubuntu-latest

    # Here is the list of specific commands this job will run. They are run in order
    steps:
      # First, we check out the repository's code using the Github Actions' "Checkout" tool.
      - name: Checkout code
        uses: actions/checkout@v3
        with:
          submodules: 'recursive'
      
      # Next, we install dev packages needed for Runtime
      - name: Install dev packages
        run: |
          sudo apt-get install -y \
          python3-dev \
          clang-format \
          protobuf-compiler \
          libprotoc-dev
      
      # Next, we install Cython
      - name: Install Cython
        run: |
            python3 -m pip install Cython
        
      # The next steps steps do the following:
      #  
      # 1) Give the program "tar" root permissions
      # 2) Retrieve cached files associated with the protobuf-c library, if they exist
      # 3) Take away root permission from the "tar" program
      #
      # We need to do this because the Cache Action uses "tar" to restore cached files
      # into the runner. However, the cached files need root permission to get restored.
      # Thus, we need to give tar root permissions to do the cache restoration, then 
      # take it away once we're done (since if the caching step fails and we do the
      # insallation of protobuf-c with root permissions, we will get permission errors)
      - name: Give tar root permissions
        run: |
            sudo chown root:root /usr/bin/tar && sudo chmod u+s /usr/bin/tar
      - name: Cache protobuf-c
        id: cache-protobuf-c
        uses: actions/cache@v3 # Uses the Github Actions' "Cache" tool
        with:
          # These are the files we cache
          path: |
              /usr/local/lib/libprotobuf-c.*
              /usr/local/lib/pkgconfig
              /usr/local/bin/protoc-*
              /usr/local/include/protobuf-c
              /usr/local/include/google
          # This is the name (key) of the cache that we look for each time
          key: libprotobuf-c
      - name: Take away tar root permissions
        run: |
          sudo chown runner:runner /usr/bin/tar && sudo chmod u+x /usr/bin/tar

      # This if statement determine whether the cache lookup was a hit (true) or miss (not true--idk, false doesn't work)
      # If the cache lookup hit, we just run "sudo ldconfig" to tell the linker where to look for
      # protobuf-c files. If the cache lookup missed, we have to install protobuf-c from scratch
      # See https://docs.github.com/en/actions/using-workflows/caching-dependencies-to-speed-up-workflows#using-the-output-of-the-cache-action
      - if: ${{ steps.cache-protobuf-c.outputs.cache-hit == 'true' }}
        name: Run ldconfig
        run: |
            sudo ldconfig
      - if: ${{ steps.cache-protobuf-c.outputs.cache-hit != 'true' }}
        name: Install protobuf-c
        run: |
            wget https://github.com/protobuf-c/protobuf-c/releases/download/v1.4.1/protobuf-c-1.4.1.tar.gz
            tar -xzf protobuf-c-1.4.1.tar.gz
            cd protobuf-c-1.4.1 && ./configure && make && sudo make install && sudo ldconfig

      # Now that we are done installing Runtime's dependencies, we build Runtime
      - name: Build
        run: |
          ./runtime build

      # And finally, we test Runtime
      - name: Test
        run: |
          ./runtime test