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Contract Testing Tutorial

This tutorial will walk you through creating your first Consumer-Driven Contract test using Pact in TAFLEX.

We will simulate a scenario where a Web App (Consumer) expects a specific response from a User Service (Provider).

1. Prerequisites​

  1. Enable Pact in your automation.properties: 
    pact.enabled=true

2. Create the Consumer Test​

In Pact, the Consumer defines the interaction. Create a test class in src/test/java/io/github/vinipx/taflex/tests/contract/UserServiceContractTest.java:

package io.github.vinipx.taflex.tests.contract;

import au.com.dius.pact.consumer.dsl.PactDslWithProvider;
import au.com.dius.pact.core.model.RequestResponsePact;
import au.com.dius.pact.core.model.annotations.Pact;
import io.github.vinipx.taflex.core.contracts.PactManager;
import org.testng.annotations.Test;

public class UserServiceContractTest {
    private PactManager pactManager = new PactManager();

    @Pact(consumer = "user-web-app", provider = "user-service")
    public RequestResponsePact createPact(PactDslWithProvider builder) {
        return builder
            .given("user exists")
            .uponReceiving("a request for user 1")
                .path("/users/1")
                .method("GET")
            .willRespondWith()
                .status(200)
                .body("{\"id\": 1, \"name\": \"John Doe\"}")
            .toPact();
    }

    @Test
    public void testContract() {
        // Test logic using the Pact mock server
    }
}

3. Run the Test and Generate the Pact​

Execute the test via Gradle:

./gradlew test --tests UserServiceContractTest

What happens?

  • Pact starts a local mock server.
  • The test interacts with the mock server.
  • Upon success, a JSON "Pact file" is generated in build/pacts/.

4. Provider Verification​

The Provider (API team) then takes this JSON file and verifies it against their real service implementation.

  1. Share the Pact file (manually or via a Pact Broker).
  2. The Provider runs their verification suite to ensure they haven't broken the contract.

For more details, refer to the Pact Testing Guide.