REST Contract Testing Demo

Overview

This project demonstrates a REST-based service that provides Hatsune Miku's message and phone number. It utilizes consumer-driven contract testing with Pact to ensure the provider meets the consumer's expectations.

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Components

1. Consumer

The consumer simulates an application that interacts with the REST service. It generates a Pact contract during testing to define the expected behavior of the provider.

Consumer Methods

• getMikuMessage():

  • Sends a GET request to /miku-message.
  • Expects a response:

    {
      "message": "Hatsune Miku says hello!"
    }

• getMikuPhoneNumber():

  • Sends a GET request to /miku-message/phone-number.
  • Expects a response:

    {
      "phoneNumber": "+81-123-456-7890"
    }

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2. Provider

The provider is a RESTful service implemented with Spring Boot. It fulfills the contract generated by the consumer, ensuring the specified endpoints return the expected data.

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Contract Testing

Workflow

1. Consumer Test:

   • Simulates the consumer's interaction with the REST service.
   • Generates a Pact file defining expected requests and responses.

2. Provider Test:

   • Starts the provider service.
   • Verifies the provider's behavior matches the Pact contract for all defined interactions.

Tests

• Consumer Test:

  • Verifies the consumer generates correct requests and handles responses.
  • Produces a Pact file stored in target/pacts.

• Provider Test:

  • Runs the provider against the Pact file.
  • Verifies endpoints respond as expected.

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How it Works

1. The Consumer defines requests for /miku-message and /miku-message/phone-number:

   • Pact generates a contract capturing these interactions.

2. The Provider tests itself against this contract:

   • Ensures it satisfies the consumer's requirements.

This approach ensures seamless integration between the consumer and provider while catching potential issues early.