Spring Boot Injecting Implementations for Prod and Test - spring-boot

Question

I'm new to spring boot and I'm trying to wrap my head around how to make dependency injection work for deployment and testing.
I have a #RestController and a supporting #Service. The service injects another class that is an interface for talking to Kafka. For the Kafka interface I have two implementations: one real and one fake. The real one I want to use in production and the fake in test.
My approach is to use two different configuration for each environment (prod and test).
#Configuration
public class AppTestConfiguration {
#Bean
public KafkaMessagePublisher kafkaMessagePublisher() {
return new KafkaMessagePublisherFakeImpl();
}
}
#Configuration
public class AppConfiguration {
#Bean
public KafkaMessagePublisher kafkaMessagePublisher() {
return new KafkaMessagePublisherImpl();
}
}
Then in my main application I would like to somehow load AppConfiguration.
#SpringBootApplication
public class DeployerServiceApiApplication {
public static void main(String[] args) {
SpringApplication.run(DeployerServiceApiApplication.class, args);
}
// TODO: somehow load here...
}
And in my test load the fake configuration somehow
#SpringBootTest
#AutoConfigureMockMvc(addFilters = false)
public class DeployerServiceApiApplicationTest {
#Autowired private MockMvc mockMvc;
// TODO: somehow load AppTestConfiguration here
#Test
public void testDeployAction() throws Exception {
...
ResultActions resultActions = mockMvc.perform(...);
...
}
}
I've spent the better part of a day trying to figure this out. What I'm trying to accomplish here is fundamental and should be straight forward yet I keep running into issues which makes me wonder if the way I'm thinking about this is all wrong.

Answer 1

Am not sure if i understand your question completely but from description i guess you wish to initialize bean based on environment. Please see below.
#Profile("test")
#Configuration
public class AppTestConfiguration {
#Bean
public KafkaMessagePublisher kafkaMessagePublisher() {
return new KafkaMessagePublisherFakeImpl();
}
}
#Profile("prod")
#Configuration
public class AppConfiguration {
#Bean
public KafkaMessagePublisher kafkaMessagePublisher() {
return new KafkaMessagePublisherImpl();
}
and then you can pass the "-Dspring.profiles.active=prod" argument while starting you application using java command or you can also specify the profile in your test case like below.
#SpringBootTest
#ActiveProfile("test")
#AutoConfigureMockMvc(addFilters = false)
public class DeployerServiceApiApplicationTest

Answer 2

Use spring profiles, you can annotate your test class with #ActiveProfiles("test-kafka") and your test configuration with #Profile("test-kafka").

Answer 3

This is pretty easy task in spring boot world
Rewrite your classes as follows:
#Profile("test")
#Configuration
public class AppTestConfiguration {
#Bean
public KafkaMessagePublisher kafkaMessagePublisher() {
return new KafkaMessagePublisherFakeImpl();
}
}
#Profile("prod")
#Configuration
public class AppConfiguration {
#Bean
public KafkaMessagePublisher kafkaMessagePublisher() {
return new KafkaMessagePublisherImpl();
}
}
This will instruct spring boot to load the relevant configuration when the "prod"/"test" specified.
Then you can start your application in production with --spring.profiles.active=prod and in the Test you can write something like this:
#SpringBootTest
#ActiveProfiles("test")
public class DeployerServiceApiApplicationTest {
...
}
If you want to run all the tests with this profile and do not want to write this ActiveProfiles annotation you can create src/test/resources/application.properties and put into it: spring.active.profiles=test