GitHub Actions for CI-CD: Automating C++ Builds and Deployments

Streamline Your C++ Workflow with GitHub Actions: From Build to Deployment

GitHub Actions is a powerful tool that allows you to automate your development workflow, including building, testing, and deploying your C++ projects. This guide will walk you through setting up a basic GitHub Actions workflow for CI/CD (Continuous Integration and Continuous Deployment), ensuring your C++ projects are built, tested, and deployed seamlessly.

1. Defining Your Workflow

First, navigate to your C++ repository on GitHub and click on "Actions." You'll see a list of suggested workflows, but for now, click on "set up a workflow yourself." GitHub will create a .github/workflows/main.yml file in your repository. This file defines the actions you want to perform. Here's a basic workflow example:

name: CI

on:
  push:
    branches: [ main ]

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2
    - name: Build
      run: |
        mkdir build
        cd build
        cmake ..
        make

In this workflow:

• name: Defines the workflow's name.
• on: Specifies the events that trigger the workflow. In this case, it runs on every push to the 'main' branch.
• jobs: Defines the set of tasks to be executed. Here, we have a single job named 'build'.
• runs-on: Specifies the operating system where the workflow will run. 'ubuntu-latest' is a common choice for C++ builds.
• steps: A sequence of actions to be performed in the job. We first use the actions/checkout@v2 action to check out your repository code. Then, we use the run step to execute a series of commands to build your C++ project.

2. Building Your C++ Project

The 'run' step executes the commands you define. In our example, we:

• Create a build directory.
• Change to the build directory.
• Use cmake to configure your build system.
• Use make to build your project.

You can modify the build steps based on your specific project requirements. For instance, you may use a different build system like qmake or scons.

3. Adding Tests and Deployment (Optional)

Once your project is built, you can add further steps to test your code and deploy it.

• Testing: You can include steps to run unit tests using tools like gtest or Catch2.
• Deployment: For deployment, you can use the following approaches:
  • Manual: After a successful build and test, the workflow can notify developers or send artifacts for manual deployment.
  • Automated: You can use actions like actions/upload-artifact@v2 to upload build artifacts to GitHub, then utilize tools like docker or aws-cli to deploy the artifacts to a server or cloud platform.

Here's an example of how to include testing and manual deployment:

  build:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2
    - name: Build
      run: |
        mkdir build
        cd build
        cmake ..
        make
    - name: Run Tests
      run: |
        cd build
        ctest -j 4
    - name: Upload Artifacts
      uses: actions/upload-artifact@v2
      with:
        name: build-artifacts
        path: build/

This code adds a step to run tests with ctest, and another step to upload the build artifacts to GitHub. You can then manually download these artifacts and deploy them to your desired environment.

4. Advanced Configurations

• Workflow Triggers: You can trigger workflows on various events, like pull requests, releases, or scheduled events using the on section in your .yml file.
• Secrets: For sensitive information like API keys, you can use GitHub Secrets. These are encrypted variables stored within your repository settings.
• Environment Variables: Use environment variables to manage configurations within your workflows.
• Caching: Speed up your builds by caching dependencies using the actions/cache@v2 action.

5. Key Takeaways

GitHub Actions provides a powerful way to automate your C++ development process. By implementing workflows for building, testing, and deploying, you can enhance your productivity and code quality. This guide offers a starting point for automating your C++ workflow. Explore the comprehensive GitHub Actions documentation for advanced features and customize your workflows to fit your specific needs.

Remember: Continuous integration and deployment are essential for modern software development practices. GitHub Actions makes it easy to streamline your C++ workflow and achieve faster and more reliable releases.