I am unable to get the test binder working for a kstream based function(doNothing) as shown below.
The same works for a non-kstream based function(uppercase). This uses a kafka binder.
@Configuration
public class CPPNotificationConfiguration {
@Bean
public Function<KStream<byte[], byte[]>, KStream<byte[], byte[]>> doNothing() {
return a -> a.flatMap((key, value) -> Collections.singleton(KeyValue.pair(key,value)));
}
@Bean
public Function<String, String> uppercase() {
return String::toUpperCase;
}
}
The bindings are configured as follows for the above lambdas
spring:
cloud.stream:
function:
definition: doNothing;uppercase
bindings:
doNothing-in-0:
destination: doNothing-in-topic
doNothing-out-0:
destination: doNothing-out-topic
uppercase-in-0:
destination: uppercase-in-topic
uppercase-out-0:
destination: uppercase-out-topic
The test cases are as follows
@SpringBootTest
@Import(TestChannelBinderConfiguration.class)
class CPPNotificationtest {
@Autowired private InputDestination input;
@Autowired private OutputDestination output;
@Test
void upperCaseTest() {
input.send(new GenericMessage<>("asdfa"), "uppercase-in-topic");
Message<byte[]> message = output.receive(100, "uppercase-out-topic");
Assertions.assertArrayEquals("asdfa".toUpperCase().getBytes(), message.getPayload());
}
@Test
void doNothingTest() {
input.send(new GenericMessage<>("asdfa".getBytes()), "doNothing-in-topic");
Message<byte[]> message = output.receive(100, "doNothing-out-topic");
Assertions.assertArrayEquals("asdfa".getBytes(), message.getPayload());
}
}
upperCaseTest runs fine. doNothingTest fails with a
java.lang.NullPointerException
at org.springframework.cloud.stream.binder.test.InputDestination.send(InputDestination.java:89)
at com.mokapos.cpp.notification.integration.UpperCaseTest.itemNotificationTest(UpperCaseTest.java:31)
On using a debugger I see that InputDestination and OutputDestination have channels related only to uppercase lambda and not the doNothing lambda/function. What am I missing here?
Relevant portion of my build.gradle
implementation "org.springframework.boot:spring-boot-starter-web"
implementation "org.springframework.boot:spring-boot-starter-logging"
implementation 'org.springframework.boot:spring-boot-starter-test'
implementation "org.springframework.boot:spring-boot-starter-actuator"
implementation "org.springframework.cloud:spring-cloud-stream"
implementation "org.springframework.cloud:spring-cloud-stream-binder-kafka"
implementation "org.springframework.cloud:spring-cloud-stream-binder-kafka-streams"
testImplementation("org.springframework.cloud:spring-cloud-stream") {
artifact {
name = "spring-cloud-stream"
extension = "jar"
type ="test-jar"
classifier = "test-binder"
}
}
