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Implementing the provider changes

The next step is to implement the changes that have been requested in the pact.

  1. Open up the terminal for your provider project.

  2. Run make test to make sure everything is passing before you start.

    1. Your test run should exit successfully, but show the failing verification from our consumers feature branch. If we didn't have enablePending set, this would exit with a failure.
    • 👉 This will run our unit tests and our Pact test which "fetch pacts for these consumer version selectors" mode. This is executed as part of the following GitHub workflow .github/workflows/build.yml
  3. Get the URL of the new pact:

    • Go to your PactFlow account, find the new pact on the consumer branch feat/new-field and click "VIEW PACT".
    • In the top right, click the 3 dots and select Copy pact URL for pactflow-example-consumer version xyz.
  4. Run PACT_URL=<PACT URL HERE> make ci_webhook. This test should correctly fail with the error Could not find key "color" in the output.

    • 👉 We run a new command here make ci_webhook. This allows us to "verify a custom pact", it works because of the code in src/product/product.consumerChange.pact.test.js
    • Rather than our product.providerChange.pact.test.js test which "fetch pacts for these consumer version selectors" mode, by running make test who workflow in GitHub is in this file .github/workflows/build.yml
    • When running make ci_webhook, The $PACT_URL is passed in when the build is triggered by a "contract requiring verification published" webhook, and allows us to verify just the changed pact against the providers main branch and any deployed (or released) versions. The workflow in GitHub is in this file .github/workflows/contract_requiring_verification_published.yml
    • We share the base Pact setup in src/product/pact.setup.js for both types of Pact verification, so both can re-use Provider States / Request filters and core setup common to both tasks.
  5. Make the test pass by adding a color field to product/product.js, and adding the new color argument to the Product initialization lines in product/product.repository.js and the provider states in product/pact.setup.js.

    constructor(id, type, name, version, color) {
    this.id = id;
    this.type = type;
    this.name = name;
    this.version = version;
    this.color = color;
    }
    constructor() {
    this.products = new Map([
    ["09", new Product("09", "CREDIT_CARD", "Gem Visa", "v1", "green")],
    ["10", new Product("10", "CREDIT_CARD", "28 Degrees", "v1", "blue")],
    ["11", new Product("11", "PERSONAL_LOAN", "MyFlexiPay", "v2", "yellow")],
    ]);
    }
    const stateHandlers = {
    "products exists": () => {
    controller.repository.products = new Map([
    ["10", new Product("10", "CREDIT_CARD", "28 Degrees", "v1","blue")],
    ]);
    },
    "products exist": () => {
    controller.repository.products = new Map([
    ["10", new Product("10", "CREDIT_CARD", "28 Degrees", "v1","blue")],
    ]);
    },
    "a product with ID 10 exists": () => {
    controller.repository.products = new Map([
    ["10", new Product("10", "CREDIT_CARD", "28 Degrees", "v1","blue")],
    ]);
    },
    "a product with ID 11 does not exist": () => {
    controller.repository.products = new Map();
    },
    };
  6. Run PACT_URL=<PACT URL HERE> make ci_webhook and you should have a passing test suite. ✅

  7. We won't commit our changes until the next step.

Expected state by the end of this step​

  • A passing provider build in Github Actions.
  • Local changes on your provider codebase that implements the features required by the feat/new-field pact on its master branch.
  • A feat/new-field pact with a failed verification result

Conclusion​

The master provider is now compatible with the feat/new-field pact, based on your local changes. However, there is still a failing verification result published for the feat/new-field pact, triggered by a webhook (contract requiring verification published) when the new pact was published.

We verified the Pact would pass against our providers main branch master by passing in the Pact URL directly, however because it was only verified on a development machine, and we don't typically publish verification results from dev machines.

The next step is getting a result back to PactFlow so that the consumer knows they are safe to merge.