unit-test-wiremock-rest-api

# Unit Testing REST APIs with WireMock ## Overview Patterns for testing external REST API integrations with WireMock: stubbing responses, verifying requests, error scenarios, and fast tests without network dependencies. ## When to Use - Testing services calling external REST APIs - Stubbing HTTP responses for predictable test behavior - Testing error scenarios (timeouts, 5xx errors, malformed responses) - Verifying request details (headers, query params, request body) ## Instructions 1. **Add dependency**: WireMock in test scope (Maven/Gradle) 2. **Register extension**: `@RegisterExtension WireMockExtension` with `dynamicPort()` 3. **Configure client**: Use `wireMock.getRuntimeInfo().getHttpBaseUrl()` as base URL 4. **Stub responses**: `stubFor()` with request matching (URL, headers, body) 5. **Execute and assert**: Call service methods, validate results with AssertJ 6. **Verify requests**: `verify()` to ensure correct API usage **If stub not matching**: Check URL encoding, header names, use `urlEqualTo` for query params. **If tests hanging**: Configure connection timeouts in HTTP client; use `withFixedDelay()` for timeout simulation. **If port conflicts**: Always use `wireMockConfig().dynamicPort()`. ## Examples ### Maven Dependencies ```xml <dependency> <groupId>org.wiremock</groupId> <artifactId>wiremock</artifactId> <version>3.4.1</version> <scope>test</scope> </dependency> <dependency> <groupId>org.assertj</groupId> <artifactId>assertj-core</artif...