gitlab-org / gitlab-ce

This documentation details the CI/CD workflow implemented in the gitlab-org/gitlab-ce repository. If the CI/CD setup is not present in the project, next steps will be highlighted.

Overview of CI/CD in GitLab CE

Continuous Integration (CI) and Continuous Deployment (CD) automate the software development process, from integration through deployment. In GitLab CE, this is streamlined via .gitlab-ci.yml file, which orchestrates pipelines to build, test, and deploy applications.

Check for CI/CD Configuration

To determine if CI/CD is set up in the repository, look for the presence of a .gitlab-ci.yml file in the root of the repository. If this file exists, the CI/CD is configured; if it does not, you will need to set it up.

Step 1: Verify CI/CD Configuration

  • Presence of CI/CD Configuration: Check for the .gitlab-ci.yml file:

    ls -a | grep .gitlab-ci.yml

  • If present, proceed to the next step.

  • If not present, you can create a new .gitlab-ci.yml file:

Creating a Basic CI/CD Configuration

Here is a basic example of what a .gitlab-ci.yml file could look like. This example defines stages for building, testing, and deploying the application.

stages:
  - build
  - test
  - deploy

build_job:
  stage: build
  script:
    - echo "Building the project..."
    - docker build -t my-image .

test_job:
  stage: test
  script:
    - echo "Running tests..."
    - docker run my-image tests

deploy_job:
  stage: deploy
  script:
    - echo "Deploying the application..."
    - ./deploy.sh

Explanation of the Configuration

  • stages: Defines the sequence of steps in the CI/CD pipeline. Each job will execute in the order specified.

  • build_job:

    • Associated with the build stage.
    • The script section contains commands executed by the runner. For example, it builds a Docker image.

  • test_job:

    • Pertains to the test stage.
    • Runs tests against the built image.

  • deploy_job:

    • Corresponds to the deploy stage.
    • Executes a deployment script.

Utilizing Docker Configuration

If your project relies on Docker, ensure that your docker-compose.yml and Dockerfile are appropriately configured to work with the CI/CD pipeline.

Example Docker Configuration

Dockerfile

The provided Dockerfile illustrates a complex multi-stage build process. 

ARG BUILD_OS=debian
FROM registry.gitlab.com/gitlab-org/gitlab-build-images/${BUILD_OS}-bookworm-ruby-3.2.4:latest AS foss

# Install dependencies
RUN apt-get update \
    && apt-get install -y xvfb unzip google-cloud-sdk-gke-gcloud-auth-plugin

This Dockerfile installs necessary dependencies for your application, such as Ruby, and configures the environment for building your application.

Docker Compose

The docker-compose.yml file provides a simplistic means to define and run multi-container Docker applications, usually including the following:

version: '3'

services:
  app:
    image: gitlab/gitlab-ce:latest

This specifies that whenever the pipeline runs, an instance of the gitlab/gitlab-ce image will be used.

Next Steps If CI/CD is Not Yet Set Up

  1. Create .gitlab-ci.yml: Utilize the basic configuration provided above as a starting point.

  2. Configure Docker: Set up the corresponding docker-compose.yml and Dockerfile files in line with your application requirements.

  3. Test Pipeline: Once set up, push your changes to the repository and observe the CI/CD pipeline run in GitLab.

  4. Refine CI/CD Process: Adjust the pipeline stages and scripts as necessary to suit your workflow and incorporate additional testing and deployment strategies.

By following the steps outlined in this documentation, a robust CI/CD workflow can be established, enhancing the efficiency and reliability of software development within the GitLab CE environment.