What is GitLab CI/CD?

GitLab CI/CD is a built-in toolset for automating the software development lifecycle within the GitLab platform. It helps developers streamline their workflow by automating tasks such as building, testing, and deploying code.

What is CI/CD?

CI/CD stands for Continuous Integration and Continuous Delivery. It’s a software development methodology that emphasizes frequent code updates, automated testing, and rapid deployment.
CI/CD automates much of manual work. When a developer pushes code changes to the repository, GitLab CI/CD automatically triggers a pipeline of jobs that build, test, and deploy the code. This allows developers to identify and fix bugs early in the development process and to deploy new features to production quickly and reliably.

Benefits of using GitLab CI/CD

Improved code quality

By automating testing, CI/CD helps to ensure that code is bug-free before it is deployed to production.

Faster releases

CI/CD allows developers to deploy new features more quickly and frequently.

Reduced risk

By automating the deployment process, CI/CD helps to reduce the risk of human error.

Increased efficiency

CI/CD frees up developers’ time so they can focus on writing code.

Improved collaboration

CI/CD provides a centralized platform for developers to track the progress of their work and collaborate on projects.

How GitLab CI/CD works

Here’s a simplified overview of how GitLab CI/CD works:

  1. A developer pushes code changes to a GitLab repository.
  2. The push triggers the pipeline defined in the .gitlab-ci.yml file.
  3. The jobs within the pipeline are executed sequentially on GitLab runners.
  4. Each job performs its specific task, such as building the code, running tests, or deploying the code to a production environment.
  5. Artifacts are generated during the pipeline execution and can be accessed later.
  6. The pipeline status is communicated through notifications and visualized in the GitLab interface.
  7. Developers can review the pipeline results and address any issues before merging the code changes.

This automated workflow allows developers to focus on writing code while GitLab CI/CD takes care of the rest, leading to faster feedback loops, improved code quality, and more efficient software development.

Key Components of GitLab CI/CD

Here’s a breakdown of the key components that make up GitLab CI/CD:

  1. Pipelines

These are automated workflows defined in a YAML file (.gitlab-ci.yml) located in the root directory of your GitLab repository. Each pipeline consists of stages and jobs that perform specific tasks:

  1. Runners

These are the workhorses of GitLab CI/CD. Runners are virtual machines that execute the jobs defined in your pipelines. GitLab offers various options:

Shared runners: Free runners provided by GitLab, suitable for small projects.

Self-hosted runners: Runners you set up on your own infrastructure, offering more control and customization.

Project runners: Dedicated runners specifically assigned to a project for increased performance and isolation.

  1. Triggers

These determine when a pipeline should be executed. Common triggers include:

Push events: When code is pushed to a branch or merged into a protected branch.

Manual triggers: Initiated manually by a user.

API triggers: Triggered by external events through API calls.

  1. Artifacts

These are files generated during the pipeline execution. They can be downloaded for later use, such as test reports or deployment logs.

  1. Variables

These store confidential information or configuration settings used by jobs within the pipeline. Variables can be defined at the project, group, or instance level.

  1. Templates

Reusable components containing pre-defined jobs and stages. This helps standardize pipelines across projects and avoid repetitive configuration.

  1. Integrations

GitLab CI/CD integrates seamlessly with various third-party tools and services, such as Slack, Docker Hub, and Kubernetes. This allows for automated notifications, containerization, and cloud deployment