Day 10: GitLab CI/CD YAML Syntax and Basics

Introduction

In today's article, we'll delve deep into the .gitlab-ci.yml file – the heart of GitLab's CI/CD process. By understanding its structure and syntax, you can create automated pipelines tailored to your project's needs.

What is .gitlab-ci.yml?

The .gitlab-ci.yml file is a YAML file that defines all the CI/CD configurations for your GitLab project. Every time you push code to your GitLab repository, the runner references this file to determine how to build, test, and deploy your application.

Basic Structure

A typical .gitlab-ci.yml file will define:

• Stages of the pipeline

• Jobs within each stage

• Scripts to run for each job

stages:
  - build
  - test
  - deploy

build_job:
  stage: build
  script:
    - echo "Building the project..."
    # You can add other build commands here.

test_job:
  stage: test
  script:
    - echo "Testing the project..."
    # Add your test scripts here.

deploy_job:
  stage: deploy
  script:
    - echo "Deploying to production..."
    # Add your deployment scripts here.

Key Elements to Know

1. Stages: These are defined in the stages list and represent the different phases of your pipeline. Jobs are executed sequentially within each stage, but stages run in parallel.

2. Jobs: Under each stage, you define different jobs. Every job has a unique name and associated scripts.

3. Scripts: These are the actual commands the runner will execute. They can be anything from shell commands to more complex scripts, depending on your needs.

Advanced Syntax

1. only and except: Determines when a job should run. For example, you might want a job to run only for specific branches.

deploy_staging:
  stage: deploy
  script:
    - deploy_to_staging.sh
  only:
    - develop

1. Variables: Allows you to define or overwrite variables for your CI/CD process.

variables:
  TEST_ENVIRONMENT: "true"

Conclusion

The .gitlab-ci.yml file is pivotal for setting up CI/CD in GitLab. By understanding its basic structure and advanced features, you can create flexible and powerful pipelines to automate your entire development workflow. Stay tuned for our next article where we explore multi-stage pipelines in more detail!

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