# GitLab CI/CD Configuration

## Table of Contents

1. [Key Commands](#key-commands)
2. [Patterns](#patterns)
3. [Decision Guide](#decision-guide)
4. [Anti-Patterns](#anti-patterns)
5. [Troubleshooting](#troubleshooting)

> **When to use**: Running Playwright tests in GitLab pipelines on merge requests, merges to main, or scheduled pipelines.

## Key Commands

```bash
npx playwright install --with-deps    # install browsers + OS deps
npx playwright test --shard=1/4       # run 1 of 4 parallel shards
npx playwright merge-reports ./blob-report  # merge shard results
npx playwright test --reporter=dot    # minimal output for CI logs
```

## Patterns

### Basic Pipeline Configuration

**Use when**: Any GitLab project with Playwright tests.

```yaml
# .gitlab-ci.yml
image: mcr.microsoft.com/playwright:v1.48.0-noble

stages:
  - install
  - test
  - report

variables:
  CI: "true"
  npm_config_cache: "$CI_PROJECT_DIR/.npm"

cache:
  key:
    files:
      - package-lock.json
  paths:
    - .npm/
    - node_modules/

setup:
  stage: install
  script:
    - npm ci
  artifacts:
    paths:
      - node_modules/
    expire_in: 1 hour

e2e:
  stage: test
  needs: [setup]
  script:
    - npx playwright test
  artifacts:
    when: always
    paths:
      - playwright-report/
      - test-results/
    expire_in: 14 days
  rules:
    - if: $CI_PIPELINE_SOURCE == "merge_request_event"
    - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
```

### Sharded Parallel Execution

**Use when**: Test suite exceeds 10 minutes. GitLab's `parallel` keyword splits across jobs automatically.
**Avoid when**: Suite runs under 5 minutes.

```yaml
image: mcr.microsoft.com/playwright:v1.48.0-noble

stages:
  - install
  - test
  - report

variables:
  CI: "true"
  npm_config_cache: "$CI_PROJECT_DIR/.npm"

cache:
  key:
    files:
      - package-lock.json
  paths:
    - .npm/
    - node_modules/

setup:
  stage: install
  script:
    - npm ci
  artifacts:
    paths:
      - node_modules/
    expire_in: 1 hour

e2e:
  stage: test
  needs: [setup]
  parallel: 4
  script:
    - npx playwright test --shard=$CI_NODE_INDEX/$CI_NODE_TOTAL
  artifacts:
    when: always
    paths:
      - blob-report/
    expire_in: 1 hour
  rules:
    - if: $CI_PIPELINE_SOURCE == "merge_request_event"
    - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH

combine-reports:
  stage: report
  needs: [e2e]
  when: always
  script:
    - npx playwright merge-reports --reporter=html ./blob-report
  artifacts:
    when: always
    paths:
      - playwright-report/
    expire_in: 14 days
```

**Config for sharded pipelines:**

```typescript
// playwright.config.ts
export default defineConfig({
  reporter: process.env.CI
    ? [["blob"], ["dot"]]
    : [["html", { open: "on-failure" }]],
});
```

### Environment Variables and Secrets

**Use when**: Tests need secrets (API keys, passwords) and should only run on merge requests or the default branch.

```yaml
image: mcr.microsoft.com/playwright:v1.48.0-noble

stages:
  - test

variables:
  CI: "true"

e2e:staging:
  stage: test
  variables:
    BASE_URL: $STAGING_URL
    TEST_PASSWORD: $TEST_PASSWORD
    API_KEY: $API_KEY
  before_script:
    - npm ci
  script:
    - npx playwright test
  artifacts:
    when: always
    paths:
      - playwright-report/
      - test-results/
    expire_in: 14 days
  rules:
    - if: $CI_PIPELINE_SOURCE == "merge_request_event"
    - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
    - when: manual
      allow_failure: true
```

**Setting variables in GitLab:**
Navigate to **Settings > CI/CD > Variables** and add:

- `STAGING_URL` -- not masked, not protected
- `TEST_PASSWORD` -- masked, protected
- `API_KEY` -- masked, protected

### Multi-Browser Matrix

**Use when**: Running Chromium on MRs and all browsers on the default branch.

```yaml
image: mcr.microsoft.com/playwright:v1.48.0-noble

stages:
  - install
  - test

variables:
  CI: "true"

setup:
  stage: install
  script:
    - npm ci
  artifacts:
    paths:
      - node_modules/
    expire_in: 1 hour

e2e:chromium:
  stage: test
  needs: [setup]
  script:
    - npx playwright test --project=chromium
  artifacts:
    when: always
    paths:
      - playwright-report/
      - test-results/
    expire_in: 14 days
  rules:
    - if: $CI_PIPELINE_SOURCE == "merge_request_event"

e2e:all-browsers:
  stage: test
  needs: [setup]
  parallel:
    matrix:
      - PROJECT: [chromium, firefox, webkit]
  script:
    - npx playwright test --project=$PROJECT
  artifacts:
    when: always
    paths:
      - playwright-report/
      - test-results/
    expire_in: 14 days
  rules:
    - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
```

### Services Integration (Database, Cache)

**Use when**: Tests need the application running alongside Playwright, or you need external services.

```yaml
stages:
  - test

e2e:integration:
  stage: test
  image: mcr.microsoft.com/playwright:v1.48.0-noble
  services:
    - name: postgres:latest
      alias: db
    - name: redis:latest
      alias: cache
  variables:
    CI: "true"
    DATABASE_URL: "postgresql://postgres:postgres@db:5432/testdb"
    REDIS_URL: "redis://cache:6379"
    POSTGRES_PASSWORD: "postgres"
    POSTGRES_DB: "testdb"
  before_script:
    - npm ci
    - npx prisma db push
    - npx prisma db seed
  script:
    - npx playwright test
  artifacts:
    when: always
    paths:
      - playwright-report/
      - test-results/
    expire_in: 14 days
  rules:
    - if: $CI_PIPELINE_SOURCE == "merge_request_event"
    - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
```

### Scheduled Nightly Regression

**Use when**: Full regression is too slow for every MR.

```yaml
e2e:nightly:
  stage: test
  image: mcr.microsoft.com/playwright:v1.48.0-noble
  before_script:
    - npm ci
  script:
    - npx playwright test --grep @regression
  artifacts:
    when: always
    paths:
      - playwright-report/
    expire_in: 30 days
  rules:
    - if: $CI_PIPELINE_SOURCE == "schedule"
```

Set up the schedule in **CI/CD > Schedules**: `0 3 * * 1-5` (3 AM UTC, weekdays).

## Decision Guide

| Scenario                             | Approach                                               | Why                                                 |
| ------------------------------------ | ------------------------------------------------------ | --------------------------------------------------- |
| Simple project, < 5 min suite        | Single `test` job using Playwright Docker image        | No sharding overhead; artifacts capture report      |
| Suite > 10 min                       | `parallel: N` with `--shard`                           | GitLab auto-assigns `CI_NODE_INDEX`/`CI_NODE_TOTAL` |
| Merge request fast feedback          | Chromium only on MRs; all browsers on main             | 3x fewer pipeline minutes on MRs                    |
| External services needed (DB, Redis) | `services:` keyword with Postgres/Redis images         | GitLab manages service lifecycle                    |
| Secrets for staging environment      | GitLab CI/CD Variables (masked + protected)            | Never hardcode secrets in `.gitlab-ci.yml`          |
| Full nightly regression              | Pipeline schedule (`CI_PIPELINE_SOURCE == "schedule"`) | Avoids blocking MR pipelines                        |
| Report browsing                      | `artifacts:` with `paths: [playwright-report/]`        | Browse directly in GitLab job artifacts UI          |

## Anti-Patterns

| Anti-Pattern                                         | Problem                                                            | Do This Instead                                                           |
| ---------------------------------------------------- | ------------------------------------------------------------------ | ------------------------------------------------------------------------- |
| Not using the Playwright Docker image                | Installing browsers every run adds 1-2 minutes                     | Use `mcr.microsoft.com/playwright:v1.48.0-noble` as base image                   |
| `artifacts: when: on_failure` only                   | No report when tests pass; can't verify results                    | Use `when: always` to capture reports regardless                          |
| No `expire_in` on artifacts                          | Artifacts accumulate and consume storage                           | Set `expire_in: 14 days` for reports, `1 hour` for intermediate artifacts |
| Hardcoding `CI_NODE_TOTAL` in shard flag             | Breaks when you change `parallel:` value                           | Use `--shard=$CI_NODE_INDEX/$CI_NODE_TOTAL`                               |
| Skipping `needs:` between stages                     | Jobs wait for all previous stage jobs, not just their dependencies | Use `needs:` for precise dependency graphs                                |
| Large `cache:` including `node_modules/` without key | Stale cache causes version conflicts                               | Key cache on `package-lock.json` hash                                     |

## Troubleshooting

### Browser launch fails: "Failed to launch browser"

**Cause**: Not using the Playwright Docker image, or using a version that doesn't match your `@playwright/test` version.

**Fix**: Match the Docker image tag to your Playwright version:

```yaml
# Check your version: npm ls @playwright/test
image: mcr.microsoft.com/playwright:v1.48.0-noble
```

### Tests hang in GitLab runner: "Navigation timeout exceeded"

**Cause**: GitLab shared runners may have limited resources.

**Fix**: Reduce workers and increase timeouts:

```typescript
export default defineConfig({
  workers: process.env.CI ? 2 : undefined,
  use: {
    navigationTimeout: process.env.CI ? 30_000 : 15_000,
  },
});
```

### Pipeline runs on every push, not just merge requests

**Cause**: Missing `rules:` configuration.

**Fix**: Add explicit rules:

```yaml
rules:
  - if: $CI_PIPELINE_SOURCE == "merge_request_event"
  - if: $CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH
```

### Services (Postgres/Redis) not reachable from tests

**Cause**: Using `localhost` instead of the service alias.

**Fix**: Use the service alias as hostname:

```yaml
services:
  - name: postgres:latest
    alias: db

variables:
  DATABASE_URL: "postgresql://postgres:postgres@db:5432/testdb"
```

### Merged report is empty after sharded run

**Cause**: Each shard job needs the `blob` reporter, not `html`.

**Fix**: Configure blob reporter for CI:

```typescript
export default defineConfig({
  reporter: process.env.CI
    ? [["blob"], ["dot"]]
    : [["html", { open: "on-failure" }]],
});
```