How to test Classes with @ConfigurationProperties and @Autowired

Question

I want to test small parts of the application that rely on properties loaded with @Autowired and @ConfigurationProperties. I am looking for a solut

Answer 1

Unit test

To avoid having to load a Spring context, we can use the Binder class, which is also used internally by Spring anyway.

// A map of my properties.
Map properties = new HashMap<>();
properties.put("my-prefix.first-property", "foo");
properties.put("my-prefix.second-property", "bar");

// Creates a source backed by my map, you can chose another type of source as needed.
ConfigurationPropertySource source = new MapConfigurationPropertySource(properties)

// Binds my properties to a class that maps them.
Binder binder = new Binder(source);
BindResult result = binder.bind("my-prefix", MyConfiguration.class);

// Should return true if bound successfully.
Assertions.assertTrue(result.isBound);

// Asserts configuration values.
MyConfiguration config = result.get();
Assertions.assertEquals("foo", config.getFirstProperty());
Assertions.assertEquals("bar", config.getSecondProperty());