DeutschMaking Configuration Properties Testable in Spring Boot
One of Spring Boot’s most elegant features is its support for binding externalised configuration to strongly typed Java beans via @ConfigurationProperties. This makes managing application settings both expressive and maintainable. However, as with any other part of our code, we should ensure that these properties are tested — especially when they encapsulate non-trivial validation or logic.
This Baeldung article on “Testing @ConfigurationProperties in Spring Boot” provides a comprehensive overview of how to do just that. The post walks through two primary approaches:
1. Using @SpringBootTest or @ConfigurationPropertiesScan: This method spins up the Spring context and leverages the full feature set of Spring Boot, enabling integration-level testing of configuration properties in a near-production environment.
2. Using @EnableConfigurationProperties with a slice of context: This approach offers a more lightweight test setup by selectively enabling only the beans under test. It’s particularly useful when you want to avoid the overhead of loading the entire application context.
The article also touches on validation using JSR-380 (Bean Validation) annotations like @NotNull and shows how to ensure those constraints are correctly enforced during tests.
What stands out to me is the practical balance between realism and performance. Full context tests give us confidence, but in many cases, targeted tests using @EnableConfigurationProperties are more efficient and just as effective.
For teams working with complex or hierarchical configurations, adopting proper tests for @ConfigurationProperties isn’t just good practice — it’s an investment in resilience. As configuration grows more central in modern microservice and cloud-native applications, ensuring its correctness becomes non-negotiable.
The article is a worthwhile read for any Spring Boot developer who cares about clean, predictable configurations. You can find it here.
For additional background on @ConfigurationProperties, the official Spring Boot documentation is also a valuable resource.