GitHub Actions Integration¶

Automate contract validation, breaking-change detection, and publishing in your CI/CD pipeline using the official Pacto CLI GitHub Action.

Quick start¶

The action is command-driven: command: setup installs the pacto binary for later run: steps, while command: validate, diff, push or doc run those operations natively.

name: Contract CI

on:
  pull_request:
    paths:
      - 'pacto.yaml'
      - 'interfaces/**'
      - 'configuration/**'
      - 'policy/**'

jobs:
  validate:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Install Pacto CLI
        uses: TrianaLab/pacto-actions@v1
        with:
          command: setup

      - name: Validate contract
        run: pacto validate .

Common workflows¶

The quick start already runs pacto validate . on every pull request to catch schema and cross-field errors before merge. The workflows below add breaking-change detection and publishing.

Detect breaking changes¶

Compare the PR contract against the published version and block breaking changes. pacto diff takes the old contract first and the new one second, and exits non-zero on a BREAKING result (see change classification rules):

      - name: Check for breaking changes
        uses: TrianaLab/pacto-actions@v1
        with:
          command: diff
          old: oci://ghcr.io/acme/my-service-pacto
          new: .
          comment-on-pr: 'true'

fail-on-breaking defaults to true, so the step blocks the merge on a breaking change and comment-on-pr posts the diff. To gate in a plain run: step instead, pacto diff oci://ghcr.io/acme/my-service-pacto . exits non-zero on the same result.

Publish on release¶

Push the contract bundle to an OCI registry when a release is created:

name: Publish Contract

on:
  release:
    types: [published]

jobs:
  push:
    runs-on: ubuntu-latest
    permissions:
      packages: write
    steps:
      - uses: actions/checkout@v4

      - name: Install Pacto CLI
        uses: TrianaLab/pacto-actions@v1
        with:
          command: setup

      - name: Push contract
        uses: TrianaLab/pacto-actions@v1
        with:
          command: push
          ref: oci://ghcr.io/${{ github.repository }}-pacto
          path: .
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

Environment-specific validation¶

Validate the contract with environment-specific overrides:

      - name: Validate production config
        run: pacto validate . --values values/production.yaml