Creating a .gitlab-ci.yml file is the first step in setting up a CI/CD (Continuous Integration and Continuous Deployment) pipeline in GitLab. A CI/CD pipeline automates the process of building, testing and deploying your application, saving time and reducing manual errors. The .gitlab-ci.yml file defines the stages, jobs, scripts, and dependencies required to build, test, and deploy your application. Here’s a comprehensive guide to help you create a .gitlab-ci.yml file from scratch.

1. Understanding the .gitlab-ci.yml File

The .gitlab-ci.yml file works by defining stages that organize into the flow of your pipeline. Inside each stage, you define some jobs, which are the tasks you want to execute, such as building, testing, or deploying the code. The scripts inside each job are the actual commands run in your pipeline. You can dependencies between jobs and save important information using artifacts, which can be then passed to the next stages. Here you have the main points of the .gitlab-ci.yml file:

• Stages: The different phases of the pipeline, such as build, test, and deploy.
• Jobs: Individual tasks to be executed within each stage.
• Scripts: Commands to be run in each job.
• Dependencies: Relationships between jobs that determine their execution order.
• Artifacts: Files generated by jobs that can be passed to subsequent jobs.