Springboot test method involve kafka producer for integration test - spring-boot

Question

I am testing a method which involve the use kafka as a producer.When I when the test i found that i just keep looping for waiting the consumer,which i have not set.
Here is method in service class:
public String Applyjob(int order_id,int apply_id){
//check order_id
DashBroad dashBroad=dashBroadRepository.findByOrder_id(order_id);
try{
if(dashBroad.getApplier_id().contains(userCoreService.findById(apply_id))){
return "you have already applied the job";
}
dashBroad.getApplier_id().add(userCoreService.getUser(apply_id)); //update the dashbroad
dashBroad.setApplier_id(dashBroad.getApplier_id());
dashBroadRepository.save(dashBroad);
//add in applications records in user entity
postApplication(apply_id,order_id);
//send notification
String notification="You have successfully applied for job id:"+order_id;
sendNotice(notification,apply_id,order_id);
return "successfully added";
} catch(IndexOutOfBoundsException exception){
return "the number of application exceed the limit";
}
}
//kafka producer
public void sendNotice(String notification,int apply_id,int order_id){
try{
LocalDateTime myDateObj = LocalDateTime.now();
DateTimeFormatter myFormatObj = DateTimeFormatter.ofPattern("dd-MM-yyyy HH:mm:ss");
String formattedDate = myDateObj.format(myFormatObj);
kafkaTemplate.send("notificationTopic",new NoticeRespond(
apply_id,formattedDate,notification
));
log.info(apply_id+"has applied job with id: "+order_id);}
catch (Exception exception){
log.error("cant found the consumer");
}
}
private void postApplication(int apply_id,int order_id){
try{
JobOrder job=jobService.findByOrderid(order_id);
User user=userCoreService.findById(apply_id);
user.getApplications().add(job);
System.out.println(job);
userCoreService.saveAndReturn(user);
log.info("add application");
}catch (IndexOutOfBoundsException exception){
String notification="You have already send to much of applications.Please delete some and try again:"+order_id;
sendNotice(notification,apply_id,order_id);
}
}
I am testing the apply job method, which involve the method of sendNotice(kafka producer method)
test code:
#SpringBootTest
#AutoConfigureMockMvc
class DashbroadServiceTest {
#Autowired
private DashbroadService dashbroadService;
#Autowired
private DashBroadRepository dashBroadRepository;
#Autowired
private UserRepository userRepository;
#Autowired
private JobRepository jobRepository;
#Autowired
private UserCoreService userCoreService;
#Test
#Transactional
void applyjob() {
List<User> list=new ArrayList<>();
User user1=new User(0,"admin","admin",null,null,"yl","sd"
,"434","dsf",null,4,2,new ArrayList<>());
User user2=new User(0,"alex","admin",null,null,"yl","sd"
,"434","dsf",null,4,2,new ArrayList<>());
userRepository.save(user1);
userRepository.save(user2);
jobRepository.save(new JobOrder(0,1,"sda",null,null,null,0,3,false,0,null));
Assertions.assertEquals("admin",userCoreService.findById(1).getUsername());
dashBroadRepository.save(new DashBroad(0,1,1,2,list,list));
String res=dashbroadService.Applyjob(1,2);
Assertions.assertEquals("successfully added",res);
}
Log:
-02-12T02:26:17.457+08:00 WARN 15971 --- [ad | producer-1] org.apache.kafka.clients.NetworkClient : [Producer clientId=producer-1] Bootstrap broker localhost:9092 (id: -1 rack: null) disconnected
2023-02-12T02:26:17.659+08:00 INFO 15971 --- [ad | producer-1] org.apache.kafka.clients.NetworkClient : [Producer clientId=producer-1] Node -1 disconnected.
2023-02-12T02:26:18.873+08:00 WARN 15971 --
It just loop the above code,but when i stop it , it pass due to the catch method.And my question is can i just set runtime error on it and let it catch the error,or build a mockconsumer for kafka or is there any method i can just ignore the part of kafka.Please help

Answer 1

The producer sends messages to Kafka independently of the consumers. Why do you think that the problem is waiting for the consumer? You probably didn't set up Kafka configuration for the test and kafkaTemplate can't connect to it.
First of all you can delegate the work of sending a message to a separate KafkaSender service using the Single Responsibility Principle (move the sendNotice method to a new KafkaSender class).
#Service
#AllArgsConstructor
public class KafkaSender {
private final KafkaTemplate<String, Object> kafkaTemplate;
public void sendNotice(String notification, int apply_id, int order_id) {
// ...
}
}
This will make it easier to test the current complex DashbroadService class.
Next, what kind of test do you want to write?
If you want to write a Unit test without Kafka, then just mock this KafkaSender bean in the test for Spring context:
#SpringBootTest
#AutoConfigureMockMvc
class DashbroadServiceTest {
// ...
#MockBean
private KafkaSender kafkaSender;
// ...
}
You will also be able to verify the calls to this mocked kafkaSender bean via Mockito.verify(...) if needed.
If you want to write an Integration or E2E test with Kafka, then use Embedded Kafka or Kafka with TestContainers (doc). In this case, you can configure the producer to connect to a running Kafka. You can also programmatically create a consumer for additional validation of messages in topics (it is not necessary to send messages through the Spring kafkaTemplate).