Wiremock – API Mocking

Module 1: API Mocking & WireMock Introduction

• Service virtualisation: why mocking enables faster testing
• WireMock vs Mockito vs MockServer comparison
• Standalone server and Java library modes
• Maven dependency and standalone JAR setup
• Running WireMock server: port configuration
• Admin API: REST management interface

Module 2: Stubs & Request Matching

• URL matching: exact, partial, regex, and path patterns
• HTTP method matching for all verbs
• Header and query parameter matching rules
• Request body: JSON equality, JSONPath, XML
• Priority: resolving stub conflicts
• Stub lifecycle and reset management

Module 3: Response Configuration

• Status codes, headers, and body types
• Response templating with Handlebars
• Binary response bodies for file downloads
• Fixed and random delay simulation
• Chunked transfer for streaming simulation
• Content negotiation response configuration

Module 4: Advanced & Stateful Behaviour

• Scenario-based stateful stub sequences
• Stub journal: recording and playback
• Proxy mode: selective pass-through requests
• Record and playback from real APIs
• Transformer extensions for dynamic responses
• Custom request matcher extensions

Module 5: Fault Simulation

• Connection reset: network failure simulation
• Empty response: timeout handling testing
• Random delay: slow API response simulation
• Chunked dribble delay for streaming tests
• Testing circuit breakers and retry logic
• Chaos testing with WireMock fault injection

Module 6: JUnit & Spring Boot Integration

• WireMockExtension for JUnit 5
• Spring Boot: spring-cloud-contract-wiremock
• Configuring RestTemplate and WebClient
• Auto-configuration in Spring integration tests
• Sharing stubs across test classes
• Per-test reset for test isolation

Module 7: Standalone & Docker Deployment

• Standalone JAR as a persistent service
• WireMock Docker container setup
• Docker Compose multi-service test environments
• Mappings and __files directory management
• Remote stub management via Admin API
• WireMock in Kubernetes environments

Module 8: Contract Testing & Best Practices

• Consumer-driven contracts with WireMock
• Pact and WireMock complementary patterns
• Microservices: isolating service dependencies
• WireMock Cloud: managed simulation platform
• High-volume stub handling performance
• Maintainable mock library design patterns

Our WireMock instructors are Java engineers and testing specialists who have used WireMock extensively in microservices architectures, enabling independent team delivery by virtualising service dependencies. They teach WireMock as part of a broader test isolation strategy — combined with Spring Boot, contract testing, and CI/CD pipeline integration.