WireMock best practices

Help teams use WireMock effectively for HTTP dependency stubbing with stable, isolated tests.

What is covered in this Skill?

• Stub isolation: per-test registration, resetAll(), avoiding leaked global stubs
• Request matching: method, path, headers, query, body patterns; when broad patterns are acceptable
• Responses: status, headers, JSON/XML bodies, bodyFileName / classpath fixtures, fault simulation (delays, errors)
• Dynamic ports and propagating base URLs into the system under test
• Verification of outbound HTTP calls and debugging unmatched requests
• Clear delegation to framework integration-test skills for test class layout and extensions

Scope: Portable WireMock behavior only. For BaseIntegrationTest, WireMockExtension, and stack-specific integration tests, use @132-java-testing-integration-testing, @322-frameworks-spring-boot-testing-integration-tests, @422-frameworks-quarkus-testing-integration-tests, or @522-frameworks-micronaut-testing-integration-tests. For OpenAPI contract quality, use @701-technologies-openapi.

Constraints

Keep recommendations at the WireMock and HTTP-stub layer unless the user explicitly asks for framework integration. After editing this repository's XML sources, regenerate skills and verify the build.

• MANDATORY: Run ./mvnw compile or mvn compile before proposing Java or Maven changes in the same change set
• FRAMEWORK: Defer @SpringBootTest / @QuarkusTest / @MicronautTest and extension setup to @132-java-testing-integration-testing or the matching 322 / 422 / 522 integration-test skill
• CONTRACTS: Defer OpenAPI document structure and linting to @701-technologies-openapi
• VERIFY: Run ./mvnw clean verify or mvn clean verify before promoting changes
• EDGE CASE: If the user goal is ambiguous, stop and ask a clarifying question before editing files or running project-wide commands
• EDGE CASE: If required context, files, credentials, or tools are missing, report the blocker explicitly and ask whether to proceed with setup or fallback guidance
• EDGE CASE: If requested changes conflict with project constraints or safety boundaries, explain the conflict and ask for user confirmation on the preferred trade-off

When to use this skill

• Design or review WireMock stubs (JSON mappings or Java DSL)
• Improve request matching, isolation, or reset strategy for HTTP mocks
• Add or fix verification of outbound HTTP calls to a WireMock server
• Debug flaky tests involving WireMock or unmatched request journals
• Stub external HTTP APIs in tests with stable fixtures and dynamic ports

Workflow

1. Read reference and assess project context

Read references/702-technologies-wiremock.md and inspect current API/context artifacts before proposing changes.

2. Gather scope and decide target improvements

Identify requested outcomes, constraints, and the minimum safe set of changes to apply.

3. Apply technology-aligned changes

Implement or refactor artifacts following the reference patterns and project conventions.

4. Run verification and report results

Execute appropriate checks and summarize what changed, what was verified, and any follow-up actions.

Reference

For detailed guidance, examples, and constraints, see references/702-technologies-wiremock.md.