gitlab-ci-patterns

# 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 ```yaml 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:1.31 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 ```yaml 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 $CI_REGISTRY_IMAGE:latest only: - main - tags ``` ## Multi-Environment Deployment ```yaml .deploy_template: &deploy_template image: bitnami/kubectl:1.31 before_script: - kubectl config set-cluster k8s --server="$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 ```yaml 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 ```yaml 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:0.58.0 script: - trivy image --exit-code 1 --severity HIGH,CRITICAL $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA allow_failure: true ``` ## Caching Strategies ```yaml # 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 ```yaml 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 ``` ## Best Practices 1. **Use specific image tags** (node:20, not node:latest) 2. **Cache dependencies** appropriately 3. **Use artifacts** for build outputs 4. **Implement manual gates** for production 5. **Use environments** for deployment tracking 6. **Enable merge request pipelines** 7. **Use pipeline schedules** for recurring jobs 8. **Implement security scanning** 9. **Use CI/CD variables** for secrets 10. **Monitor pipeline performance** ## Related Skills - `github-actions-templates` - For GitHub Actions - `deployment-pipeline-design` - For architecture - `secrets-management` - For secrets handling