CI/CD for C++ Projects: Setting Up GitHub Actions

CI/CD for C++ projects: setting up GitHub Actions

Modern C++ development requires not only writing quality code, but also setting up processes for its building, testing, and deployment. CI/CD (Continuous Integration / Continuous Deployment) is a practice that allows automating these processes, reducing the time between writing code and delivering it to users. In this article, we will look at how to set up CI/CD for C++ projects using GitHub Actions — a powerful and free tool built into GitHub.

GitHub Actions allows you to create automatic workflows that are triggered by certain events: push to a repository, creating a pull request, release, and others. For C++ projects, this is especially useful as it helps ensure that the code builds on different platforms and contains no regressions.

Basics of GitHub Actions for C++

GitHub Actions uses YAML files to describe workflows. Each workflow consists of one or more jobs that run on virtual machines (runners). For C++ projects, Ubuntu, Windows, and macOS runners are typically used. Let's look at the basic structure of a workflow file.

name: C++ CI

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

jobs:  build:    runs-on: ubuntu-latest

    steps:    - uses: actions/checkout@v4

    - name: Install dependencies      run: |        sudo apt-get update        sudo apt-get install -y cmake g++ libboost-all-dev

    - name: Configure CMake      run: cmake -B build -DCMAKE_BUILD_TYPE=Release

    - name: Build      run: cmake --build build --config Release

    - name: Test      run: cd build && ctest --output-on-failure

This workflow runs on push to the main and develop branches, as well as when creating a pull request to main. It installs dependencies (CMake, g++, Boost), configures the project, builds it, and runs tests.

Multi-platform build for C++ projects

One of the main advantages of CI/CD for C++ is the ability to automatically check the build on multiple platforms. This is critically important, as C++ code can behave differently on different OSes and compilers. GitHub Actions makes it easy to organize a build matrix.

jobs:  build:    strategy:      matrix:        os: [ubuntu-latest, windows-latest, macos-latest]        compiler: [g++, clang++]        include:          - os: ubuntu-latest            compiler: g++            cmake_flags: -DCMAKE_CXX_COMPILER=g++-11          - os: ubuntu-latest            compiler: clang++            cmake_flags: -DCMAKE_CXX_COMPILER=clang++-14          - os: windows-latest            compiler: msvc            cmake_flags: -DCMAKE_CXX_COMPILER=cl          - os: macos-latest            compiler: clang++            cmake_flags: -DCMAKE_CXX_COMPILER=clang++

    runs-on: ${{ matrix.os }}

    steps:    - uses: actions/checkout@v4

    - name: Install dependencies (Ubuntu)      if: matrix.os == 'ubuntu-latest'      run: |        sudo apt-get update        sudo apt-get install -y cmake g++-11 clang-14 libboost-all-dev

    - name: Install dependencies (macOS)      if: matrix.os == 'macos-latest'      run: |        brew update        brew install cmake boost

    - name: Install dependencies (Windows)      if: matrix.os == 'windows-latest'      run: |        choco install cmake boost-msvc-14.3

    - name: Configure CMake      run: cmake -B build ${{ matrix.cmake_flags }} -DCMAKE_BUILD_TYPE=Release

    - name: Build      run: cmake --build build --config Release

    - name: Test      run: |        if [ "${{ runner.os }}" == "Windows" ]; then          cd build && ctest -C Release --output-on-failure        else          cd build && ctest --output-on-failure        fi

In this example