How to test the binding of configuration properties in Spring Boot?

Question

I have a Spring Boot Application with the following (simplified) configuration class

@ConfigurationProperties(prefix = "prefix")
@Configuration
public class ConfigProperties {
    @NotNull
    public Duration snapshotOffset;

}

My code is working, but I would like know how I can write unit tests for the binding process with different property files as input?

Answer 1

You can configure test properties files by using the locations or value attribute of the TestPropertySource annotation:

//Typically, @TestPropertySource will be used in conjunction with @ContextConfiguration.
@ContextConfiguration
@TestPropertySource("/test.properties") 
public class Test {
    // class body...
}