https://devops-monk.com/tags/testing/Recent content in Testing on Devops MonkHugoen-usSun, 03 May 2026 00:00:00 +0000https://devops-monk.com/tutorials/spring-boot/spring-boot-integration-testing/Sun, 03 May 2026 00:00:00 +0000https://devops-monk.com/tutorials/spring-boot/spring-boot-integration-testing/Integration tests verify that all layers work together — HTTP → controller → service → repository → database. This article shows how to write them efficiently with Testcontainers and manage test isolation. @SpringBootTest — The Full Context @SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT) class OrderIntegrationTest { // Loads the FULL Spring ApplicationContext // Everything: controllers, services, repositories, security // Starts on a random port (avoids port conflicts when running tests in parallel) } WebEnvironment options Option What it starts Use for RANDOM_PORT Embedded server on random port Full HTTP round-trip tests DEFINED_PORT Embedded server on configured port When you need a fixed port MOCK (default) No real server, MockMvc available Fast tests without real HTTP NONE No server at all Service/repo tests only Testcontainers — Real Database <dependency> <groupId>org.https://devops-monk.com/2026/05/spring-boot-testcontainers/Sun, 03 May 2026 00:00:00 +0000https://devops-monk.com/2026/05/spring-boot-testcontainers/Testcontainers spins up real Docker containers for your tests — a real PostgreSQL database, a real Redis, a real Kafka broker. No more mocking JDBC connections or in-memory H2 databases that behave differently from production. Spring Boot 3.1 added @ServiceConnection, which removes the boilerplate of configuring connection URLs manually. This guide covers the right patterns for fast, reliable integration tests with Testcontainers. Why Testcontainers Over H2 Teams use H2 in-memory databases for testing because it’s fast.https://devops-monk.com/tutorials/spring-boot/spring-boot-security-testing/Sun, 03 May 2026 00:00:00 +0000https://devops-monk.com/tutorials/spring-boot/spring-boot-security-testing/Security tests verify that your endpoints behave correctly for different users, roles, and authentication states. This article covers the full toolkit — from simple annotations to custom security contexts. Setup <dependency> <groupId>org.springframework.security</groupId> <artifactId>spring-security-test</artifactId> <scope>test</scope> </dependency> spring-boot-starter-test includes this automatically. @WithMockUser — Simple Role-Based Tests The simplest way to run a test as an authenticated user: @WebMvcTest(OrderController.class) class OrderControllerSecurityTest { @Autowired MockMvc mockMvc; @MockBean OrderService orderService; // No authentication @Test void unauthenticatedUserIsRejected() throws Exception { mockMvc.https://devops-monk.com/tutorials/spring-boot/spring-boot-unit-testing/Sun, 03 May 2026 00:00:00 +0000https://devops-monk.com/tutorials/spring-boot/spring-boot-unit-testing/Good tests catch regressions, document behavior, and give you confidence to refactor. Bad tests slow you down. This article covers unit testing at the service layer — fast, focused, no Spring context needed. Setup <!-- spring-boot-starter-test includes JUnit 5, Mockito, AssertJ --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> This pulls in: JUnit 5 (Jupiter) — test runner and assertions Mockito — mocking framework AssertJ — fluent assertions (assertThat(...)) Hamcrest — matcher library MockMvc — web layer testing (next article) Testcontainers integration Unit Tests vs Integration Tests Unit Integration Scope One class in isolation Multiple components together Dependencies All mocked Real or near-real Speed Milliseconds Seconds to minutes Context No Spring context Spring context loads Purpose Logic correctness Component interaction Start with unit tests.https://devops-monk.com/tutorials/spring-boot/spring-boot-repository-testing/Sun, 03 May 2026 00:00:00 +0000https://devops-monk.com/tutorials/spring-boot/spring-boot-repository-testing/Repository tests verify your queries work correctly against a real database. Spring Boot’s @DataJpaTest starts a minimal slice — only JPA components — making tests fast while still catching real SQL issues. @DataJpaTest — What It Loads @DataJpaTest is a test slice annotation: @DataJpaTest class OrderRepositoryTest { // Spring loads: // - Your @Entity classes // - Your @Repository interfaces // - JPA infrastructure (EntityManager, transactions) // - An in-memory H2 database (by default) // // Spring does NOT load: // - @Service, @Controller, @Component classes // - Security configuration // - The full ApplicationContext } Each test method runs in a transaction that’s rolled back at the end — no data pollution between tests.https://devops-monk.com/tutorials/spring-boot/spring-boot-web-layer-testing/Sun, 03 May 2026 00:00:00 +0000https://devops-monk.com/tutorials/spring-boot/spring-boot-web-layer-testing/Controller tests verify HTTP mapping, request parsing, validation, serialization, and security — without starting a full server. @WebMvcTest + MockMvc gives you a fast, focused web layer test. @WebMvcTest — What It Loads @WebMvcTest(OrderController.class) class OrderControllerTest { // Spring loads: // - Your @Controller class (and its dependencies) // - DispatcherServlet, MVC configuration // - Jackson ObjectMapper // - Security (if configured) // // Spring does NOT load: // - @Service, @Repository beans // - Database, JPA // // You @MockBean all services } Basic Controller Test @WebMvcTest(OrderController.