GitLab CI Integration

Configure Copybara to run in GitLab CI/CD pipelines.

Basic Pipeline

.gitlab-ci.yml

stages:
  - sync

copybara-sync:
  stage: sync
  image: docker.io/copybara/copybara:latest
  variables:
    GIT_STRATEGY: clone
  script:
    - copybara migrate copy.bara.sky --git-destination-url https://oauth2:${GITLAB_TOKEN}@gitlab.com/org/dest-repo.git
  rules:
    - if: $CI_PIPELINE_SOURCE == "schedule"
    - if: $CI_PIPELINE_SOURCE == "web"

Authentication

GitLab Token

Create a Project Access Token or Personal Access Token:

1. Go to Settings > Access Tokens
2. Create token with read_repository and write_repository scopes
3. Add as CI/CD variable GITLAB_TOKEN

variables:
  GIT_AUTHOR_NAME: "Copybara Bot"
  GIT_AUTHOR_EMAIL: "copybara@example.com"
  GIT_COMMITTER_NAME: "Copybara Bot"
  GIT_COMMITTER_EMAIL: "copybara@example.com"

script:
  - git config --global credential.helper store
  - echo "https://oauth2:${GITLAB_TOKEN}@gitlab.com" >> ~/.git-credentials
  - copybara migrate copy.bara.sky

Cross-Platform (GitLab to GitHub)

variables:
  GITLAB_TOKEN: $GITLAB_TOKEN
  GITHUB_TOKEN: $GITHUB_TOKEN

script:
  - echo "https://oauth2:${GITLAB_TOKEN}@gitlab.com" >> ~/.git-credentials
  - echo "https://x-access-token:${GITHUB_TOKEN}@github.com" >> ~/.git-credentials
  - copybara migrate copy.bara.sky

Scheduled Syncs

Set up periodic synchronization:

copybara-sync:
  stage: sync
  rules:
    - if: $CI_PIPELINE_SOURCE == "schedule"
  script:
    - copybara migrate copy.bara.sky --ignore-noop

Create a schedule in CI/CD > Schedules:

• Interval: 0 */6 * * * (every 6 hours)
• Target branch: main

Merge Request Workflows

Sync on merge request events:

copybara-mr-sync:
  stage: sync
  rules:
    - if: $CI_MERGE_REQUEST_IID && $CI_MERGE_REQUEST_TARGET_BRANCH_NAME == "main"
      when: on_success
  script:
    - copybara migrate copy.bara.sky --ignore-noop

Multi-Project Setup

Sync to multiple destinations:

stages:
  - sync

.sync-template: &sync-template
  image: docker.io/copybara/copybara:latest
  stage: sync
  before_script:
    - git config --global credential.helper store
    - echo "https://oauth2:${GITLAB_TOKEN}@gitlab.com" >> ~/.git-credentials

sync-project-a:
  <<: *sync-template
  script:
    - copybara migrate copy.bara.sky project-a
  rules:
    - if: $CI_PIPELINE_SOURCE == "schedule"
    - changes:
        - "project-a/**"

sync-project-b:
  <<: *sync-template
  script:
    - copybara migrate copy.bara.sky project-b
  rules:
    - if: $CI_PIPELINE_SOURCE == "schedule"
    - changes:
        - "project-b/**"

Caching

Cache Copybara’s working directory:

copybara-sync:
  cache:
    key: copybara-cache
    paths:
      - .copybara/
  variables:
    COPYBARA_LOCAL_REPO_DIR: ${CI_PROJECT_DIR}/.copybara
  script:
    - copybara migrate copy.bara.sky

Error Handling

Handle failures gracefully:

copybara-sync:
  script:
    - |
      copybara migrate copy.bara.sky --ignore-noop || {
        exit_code=$?
        if [ $exit_code -eq 48 ]; then
          echo "No changes to sync - this is OK"
          exit 0
        fi
        exit $exit_code
      }
  allow_failure: false

Note

Exit code 48 indicates “no changes to migrate” which may be acceptable in scheduled runs.

Notifications

Send Slack notification on failure:

copybara-sync:
  script:
    - copybara migrate copy.bara.sky
  after_script:
    - |
      if [ "$CI_JOB_STATUS" == "failed" ]; then
        curl -X POST -H 'Content-type: application/json' \
          --data '{"text":"Copybara sync failed: '$CI_JOB_URL'"}' \
          $SLACK_WEBHOOK_URL
      fi

Example: Full Pipeline

Complete pipeline with validation, sync, and notifications:

stages:
  - validate
  - sync
  - notify

variables:
  COPYBARA_IMAGE: docker.io/copybara/copybara:latest

validate-config:
  stage: validate
  image: $COPYBARA_IMAGE
  script:
    - copybara validate copy.bara.sky
  rules:
    - changes:
        - copy.bara.sky

sync-to-dest:
  stage: sync
  image: $COPYBARA_IMAGE
  before_script:
    - git config --global credential.helper store
    - echo "https://oauth2:${GITLAB_TOKEN}@gitlab.com" >> ~/.git-credentials
  script:
    - copybara migrate copy.bara.sky --ignore-noop
  rules:
    - if: $CI_PIPELINE_SOURCE == "schedule"
    - if: $CI_COMMIT_BRANCH == "main"
      changes:
        - "src/**"

notify-success:
  stage: notify
  needs:
    - sync-to-dest
  script:
    - echo "Sync completed successfully"
  rules:
    - if: $CI_PIPELINE_SOURCE == "schedule"
      when: on_success

Next Steps

• GitHub Actions - Alternative CI platform
• Authentication - Credential setup
• Automation patterns - Advanced workflows