Spring Boot testing with different service class - spring

Question

I have a pretty basic question, apologies if it has been asked before. I fear I may not be using the right words, this is my first rodeo with Spring.
I have a RestController declared as such:
#RestController
class TelemetryController {
#Autowired
lateinit var service: TelemetryService
//...
}
with a concrete implementation of TelemetryService as such in our main module:
#Service
class ConcreteTelemetryService : TelemetryService {
// some production code
}
I then have a service I want to use in my controller during tests (inside our test module:
#Service
class TestingTelemetryService : TelemetryService {
// some test code using local data
}
Critically, I have do NOT want to use Mockito for this, as the implementation of the tests require very specific setup that is not appropriate for Mockito.
My test is declared as such:
#RunWith(SpringRunner::class)
#SpringBootTest
#AutoConfigureMockMvc
class HowDoInjectServiceExampleTest {
#Autowired
lateinit var mockMvc: MockMvc
}
How do I get my TestingTelemetryService inside my controller in this instance?

Answer 1

There are various way to achieve this but I would recommend to use Spring Profiles.
Use the default profile with the concrete implementation. This bean will be used if no profile is specified.
#Profile("default")
#Service
class ConcreteTelemetryService : TelemetryService {
// some production code
}
Add the profile "test" to the test implementation.
#Profile("test)
#Service
class TestingTelemetryService : TelemetryService {
// some test code using local data
}
Now you can start your test with
-Dspring.profiles.active=test
Read more about profiles here:
https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-profiles.html

Answer 2

If your TestingTelemetryService is in same package as HowDoInjectServiceExampleTest then you can simply autowire test bean like
#RunWith(SpringRunner::class)
#SpringBootTest
#AutoConfigureMockMvc
class HowDoInjectServiceExampleTest {
#Autowired
lateinit var mockMvc: MockMvc
#Autowired
var service: TestingTelemetryService
}
if not then you should define some TestConfiguration and programatically define bean with service name and use it using #Qualifier in test to resolve which bean to use (in your case its test bean)