GitLab CI Patterns

Comprehensive GitLab CI/CD pipeline patterns for automated testing, building, and deployment.

Purpose

Create efficient GitLab CI pipelines with proper stage organization, caching, and deployment strategies.

When to Use

• Automate GitLab-based CI/CD

• Implement multi-stage pipelines

• Configure GitLab Runners

• Deploy to Kubernetes from GitLab

• Implement GitOps workflows

Basic Pipeline Structure

stages:

• build
• test
• deploy

variables: DOCKER_DRIVER: overlay2 DOCKER_TLS_CERTDIR: "/certs"

build: stage: build image: node:20 script: - npm ci - npm run build artifacts: paths: - dist/ expire_in: 1 hour cache: key: ${CI_COMMIT_REF_SLUG} paths: - node_modules/

test: stage: test image: node:20 script: - npm ci - npm run lint - npm test coverage: '/Lines\s*:\s*(\d+.\d+)%/' artifacts: reports: coverage_report: coverage_format: cobertura path: coverage/cobertura-coverage.xml

deploy: stage: deploy image: bitnami/kubectl:latest script: - kubectl apply -f k8s/ - kubectl rollout status deployment/my-app only: - main environment: name: production url: https://app.example.com

Docker Build and Push

build-docker: stage: build image: docker:24 services: - docker:24-dind before_script: - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY script: - docker build -t $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA . - docker build -t $CI_REGISTRY_IMAGE:latest . - docker push $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA - docker push $CI_REGISTRY_IMAGE:latest only: - main - tags

Multi-Environment Deployment

.deploy_template: &deploy_template image: bitnami/kubectl:latest before_script: - kubectl config set-cluster k8s --server="$KUBE_URL" --insecure-skip-tls-verify=true - kubectl config set-credentials admin --token="$KUBE_TOKEN" - kubectl config set-context default --cluster=k8s --user=admin - kubectl config use-context default

deploy:staging: <<: *deploy_template stage: deploy script: - kubectl apply -f k8s/ -n staging - kubectl rollout status deployment/my-app -n staging environment: name: staging url: https://staging.example.com only: - develop

deploy:production: <<: *deploy_template stage: deploy script: - kubectl apply -f k8s/ -n production - kubectl rollout status deployment/my-app -n production environment: name: production url: https://app.example.com when: manual only: - main

Terraform Pipeline

stages:

• validate
• plan
• apply

variables: TF_ROOT: ${CI_PROJECT_DIR}/terraform TF_VERSION: "1.6.0"

before_script:

• cd ${TF_ROOT}
• terraform --version

validate: stage: validate image: hashicorp/terraform:${TF_VERSION} script: - terraform init -backend=false - terraform validate - terraform fmt -check

plan: stage: plan image: hashicorp/terraform:${TF_VERSION} script: - terraform init - terraform plan -out=tfplan artifacts: paths: - ${TF_ROOT}/tfplan expire_in: 1 day

apply: stage: apply image: hashicorp/terraform:${TF_VERSION} script: - terraform init - terraform apply -auto-approve tfplan dependencies: - plan when: manual only: - main

Security Scanning

include:

• template: Security/SAST.gitlab-ci.yml
• template: Security/Dependency-Scanning.gitlab-ci.yml
• template: Security/Container-Scanning.gitlab-ci.yml

trivy-scan: stage: test image: aquasec/trivy:latest script: - trivy image --exit-code 1 --severity HIGH,CRITICAL $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA allow_failure: true

Caching Strategies

Cache node_modules

build: cache: key: ${CI_COMMIT_REF_SLUG} paths: - node_modules/ policy: pull-push

Global cache

cache: key: ${CI_COMMIT_REF_SLUG} paths: - .cache/ - vendor/

Separate cache per job

job1: cache: key: job1-cache paths: - build/

job2: cache: key: job2-cache paths: - dist/

Dynamic Child Pipelines

generate-pipeline: stage: build script: - python generate_pipeline.py > child-pipeline.yml artifacts: paths: - child-pipeline.yml

trigger-child: stage: deploy trigger: include: - artifact: child-pipeline.yml job: generate-pipeline strategy: depend

Reference Files

• assets/gitlab-ci.yml.template

• Complete pipeline template

• references/pipeline-stages.md

• Stage organization patterns

Best Practices

• Use specific image tags (node:20, not node:latest)

• Cache dependencies appropriately

• Use artifacts for build outputs

• Implement manual gates for production

• Use environments for deployment tracking

• Enable merge request pipelines

• Use pipeline schedules for recurring jobs

• Implement security scanning

• Use CI/CD variables for secrets

• Monitor pipeline performance

Related Skills

• github-actions-templates

• For GitHub Actions

• deployment-pipeline-design

• For architecture

• secrets-management

• For secrets handling