Pact Manifest

Pact Manifest is a Node.js library to publish pact contracts to a broker using a manifest.

Context

Pact is a collection of frameworks that implement the Consumer-Driven Contracts pattern to enable lean testing of API contracts between consumers and providers.

Why

When working in a CI/CD-enabled workflow, the consumer and provider are deploying their artifacts quite often and any dependency on providers's API that isn't ready is hidden behind feature flags, api versioning or other means. This ensures that the consumer can deploy his version without waiting with a long-lived branch for the entire API contract to be implemented by its provider.

How

The library collects the pact contract files and creates or updates a manifest file with the path to the file, and a default tag. With the manifest file ready, the library can be instructed to publish the contracts to a broker based on their tags.

To accompany the manifest file, a suggested workflow is to use a default tag of develop and publish these pacts to the broker. Once the provider implements the contract, it is required on the consumer side to manually edit the manifest file and update the relevant contract file(s) to specify a production flag instead of develop.

Installation

yarn add --dev pact-manifest

Usage

Manifest Manager

const ManifestManager = require('./src/manifestManager')

const manifestManager = new ManifestManager({
  basePath: '/Users/lirantal/projects/forks/myGitProject',
  manifestFile: '/tmp/pact_manifest.json',
  pactFilesPath: 'test/pacts/*.json',
  pactDefaultTag: 'develop'
})

const manifest = await manifestManager.createManifest()

Manifest Publisher

const ManifestPublisher = require('./src/manifestPublisher')

const pactBroker = 'https://test.pact.dius.com.au'
const pactBrokerUsername = 'username'
const pactBrokerPassword = 'password'
const consumerVersion = '1.0.0' // should ideally get this package.json

// Obtain the pacts manifest that ManifestManager creates
// and use the `getManifestsByTag` method to get an object tree
// representation that can be easily iterated to publish the pacts
const manifestByTag = manifestManager.getManifestsByTag(manifest)

let publishedPacts = []

// Iterate on each tag and publish the pact files for it to the broker
for (let [tag, pactFiles] of Object.entries(manifest)) {
  const manifestPublisher = new ManifestPublisher({
	pactFiles: pactFiles,
	broker: {
	  pactBroker: pactBroker,
	  pactBrokerUsername: pactBrokerUsername,
	  pactBrokerPassword: pactBrokerPassword
	},
	consumerVersion: consumerVersion,
	tags: [tag]
  })

  publishedPacts.push(manifestPublisher.publish())
}

const res = await Promise.all(publishedPacts)

Related resources

• Pact documentation
• Pact.js implementation
• Pact runner on a Docker container

Tests

Project tests:

yarn run test

Project linting:

yarn run lint

Coverage

yarn run test:coverage

Contributing

Commit Guidelines

The project uses the commitizen tool for standardizing changelog style commit messages which you can follow by running yarn run commit instead of just git commit

git add <file1> <file2>
yarn run commit