aljorhythm/learn-pact

Requisites

• https://github.com/casey/just
• https://pnpm.io/
• https://formulae.brew.sh/formula/docker
• https://formulae.brew.sh/formula/docker-compose
• if required https://github.com/abiosoft/colima

Demo

Consumer: Person Provider: Food

Broker: Start broker

(cd broker && just restart)

Broker: Open web ui with no contracts

(cd broker && just browser)

Provider: verify and fail

provider/provider/person.test.js

(cd provider && just verify)

Consumer: test

consumer/contracts/food.test.js

(cd consumer && just test)

See pacts

consumer/pact/pacts

Consumer: publish contract

(cd consumer && just publish-contracts)

Open web ui see updated contract

(cd broker && just browser)

Provider: verify

(cd provider && just verify)

TDD Consumer-driven contract tests

Consumer: Edit assumptions & expectations

consumer/contracts/food.test.js

results: [{ name: "Chicken" }]
[{ name: "Chicken" }]

(cd consumer && just test)

Consumer: Fix implementation

consumer/contracts/food.test.js

const originalBody = await (await fetch(`${this.baseUrl}/food`)).json()
return originalBody.results

(cd consumer && just test)

consumer/pact/pacts

git add . && git commit

parse response from Food GET /food

Consumer: publish updated contract

(cd consumer && just publish-contracts)

Provider: Run verification and fail

(cd provider && just verify)

Provider: Satisfy contract

  res.end(
    JSON.stringify({
      results: [{ name: "Chicken" }],
    })
  );