Spring Test Service Autowiring resulting in null - spring

Question

I am able to run a Rest Controller PUT method that uses a Autowired #Service as expected via the Spring Boot Application. The same Autowiring is failing while trying to perform a Spring JUnit Test. I have tried reading through multiple threads with similar issues. I made sure I am NOT creating the #Service through the "new" keyword and I tried Context Configuration and other methods .. but all seems to be in vain. I am not sure where I am going wrong.
My Spring Boot Application class -
#SpringBootApplication
#ComponentScan({
"com.initech.myapp.*"
})
public class IngestionServerApplication {
private static final Log logger = LogFactory.getLog(IngestionServerApplication.class);
public static void main(String[] args) {
SpringApplication.run(IngestionServerApplication.class, args);
logger.info("Ingestion Server Application started...");
}
}
Rest Controller Class -
package com.initech.myapp.ingestion.controller;
#RestController
public class IngestionController extends BaseRestController {
private static final Log logger = LogFactory.getLog(IngestionController.class);
// This variable is getting "null" autowiring if invoked
// via Spring Unit Testing framework while it is injected fine via
// Spring Boot app invocation.
#Autowired
public IngestionPayloadProcessor payloadProcessor;
#RequestMapping(path = "/ingest", method = RequestMethod.PUT,
consumes = {
MediaType.APPLICATION_JSON_VALUE,
MediaType.APPLICATION_XML_VALUE
},
produces = {
MediaType.APPLICATION_JSON_VALUE
})
public IngestionSuccessResponse ingest(#RequestHeader(value = "authToken", required = true) String authToken,
#RequestBody String jsonBody) throws Exception {
IngestionPayload ingestionPayload = new IngestionPayload();
ingestionPayload.setAuthToken(authToken);
ingestionPayload.setJsonBody(jsonBody);
IngestionSuccessResponse ingestionSuccessResponse = payloadProcessor.process(ingestionPayload);
return ingestionSuccessResponse;
}
}
Service Class
package com.initech.myapp.ingestion.app.service;
#Service
#ImportResource({"spring.xml"})
public class IngestionPayloadProcessor {
private static final Log logger = LogFactory.getLog(IngestionPayloadProcessor.class);
#Resource(name = "kafkaConfig")
private Properties kafkaConfig;
#Value("${kakfaTopic}")
private String kakfaTopic;
public IngestionSuccessResponse process(IngestionPayload ingestionPayload) throws Exception {
try {
IngestionSuccessResponse ingestionSuccessResponse = buildSuccessResponse(ingestionPayload);
return ingestionSuccessResponse;
}
catch (IllegalStateException e)
{
logger.error("Encountered exception while dropping message in Kafka... " + e.getMessage());
throw e;
}
}
}
private buildSuccessResponse() { ... }
Spring Unit Testing
#RunWith(SpringRunner.class)
#ContextConfiguration(locations = "classpath*:/spring.xml")
#WebMvcTest(IngestionServerApplication.class)
public class IngestionServerApplicationTests {
#Autowired
private MockMvc mockMvc;
#Before
public void setUp() throws Exception {
mockMvc = MockMvcBuilders.standaloneSetup(
new IngestionServiceController())
.build();
}
#Test
public void testIngestService() throws Exception {
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.add("authToken","safdafio12312asdfs23");
RequestBuilder requestBuilder = put("/ingest").content("{'testKey' : 'testVal'}").accept(MediaType.APPLICATION_JSON).headers(httpHeaders);
this.mockMvc.perform(requestBuilder).andExpect(status().isOk());
}
}
Error Logs
2016-08-10 19:24:36.500 DEBUG 7505 --- [ main] m.m.a.RequestResponseBodyMethodProcessor : Read [class java.lang.String] as "application/json" with [org.springframework.http.converter.StringHttpMessageConverter#49aa766b]
2016-08-10 19:24:36.510 DEBUG 7505 --- [ main] .m.m.a.ExceptionHandlerExceptionResolver : Resolving exception from handler [public com.initech.myapp.ingestion.model.IngestionSuccessResponse com.initech.myapp.ingestion.app.controller.myappIngestionServiceController.ingest(java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String,java.lang.String) throws java.lang.Exception]: java.lang.NullPointerException
2016-08-10 19:24:36.512 DEBUG 7505 --- [ main] .m.m.a.ExceptionHandlerExceptionResolver : Invoking #ExceptionHandler method: public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> com.initech.myapp.base.controller.BaseRestController.handleException(java.lang.Exception,javax.servlet.http.HttpServletRequest)
This is the error handler...
2016-08-10 19:24:36.514 INFO 7505 --- [ main] p.d.i.a.c.myappIngestionServiceController : > handleNoResultException
2016-08-10 19:24:36.574 DEBUG 7505 --- [ main] o.s.w.s.m.m.a.HttpEntityMethodProcessor : Written [{status=500, authToken=6acb1a5c-2ced-4690-95b3-eb7957c7c28a, error=null}] as "application/json" using [org.springframework.http.converter.json.MappingJackson2HttpMessageConverter#50d3bf39]
java.lang.AssertionError: Status
Expected :200
Actual :500
Note that I have debugged through the test and I can see that the NullPointer exception is thrown at the below line in the Rest Controller Class as the payloadProcessor object is null.
IngestionSuccessResponse ingestionSuccessResponse = payloadProcessor.process(ingestionPayload);
=====
Unit Test with Mock objects: (This is working as expected)
#RunWith(SpringRunner.class)
#ActiveProfiles("dev")
#SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
#AutoConfigureMockMvc
public class IngestionServerUnitTests {
#Autowired
private MockMvc mockMvc;
#MockBean
private IngestionPayloadProcessor processor;
// I was able to get this to work by removing the setUp() method
// that was originally in my code. It was trying to build a new instance
// of the REST controller and then run the "perform" on top of it
// which was causing the test to fail I assume!
/*#Before
public void setUp() throws Exception {
mockMvc = MockMvcBuilders.standaloneSetup(
new IngestionServiceController())
.build();
}*/
#Test
public void testIngestService() throws Exception {
IngestionSuccessResponse ingestionSuccessResponse = new IngestionSuccessResponse();
ingestionSuccessResponse.setStatusCode("200");
ingestionSuccessResponse.setRequestId("6acb1a5c-2ced-4690-95b3-eb7957c7c28a");
ingestionSuccessResponse.setReceivedTimestamp("2016-08-09T19:43:30.02234312");
given(this.processor.process(anyObject())).willReturn(ingestionSuccessResponse);
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.add("Authorization","5e18685c95b34690");
RequestBuilder requestBuilder = put("/ingest").content("<test>test data</test>").accept(MediaType.APPLICATION_JSON).headers(httpHeaders);
this.mockMvc.perform(requestBuilder).andExpect(status().isOk());
}
}

Answer 1

When you specify #WebMvcTest there are only certain components of your application that are added to the ApplicationContext. The annotation is actually a composition of a bunch of other annotations as described in the docs: https://docs.spring.io/spring-boot/docs/current/api/org/springframework/boot/test/autoconfigure/web/servlet/WebMvcTest.html
Based on this your IngestionPayloadProcessor doesn't get instantiated as a bean, and shouldn't as you are telling the test to only run tests for the web layer. What you need to do is specify a #MockBeanfor the IngestionPayloadProcessor within the test and then define a mock for the method that the controller is calling.
#RunWith(SpringRunner.class)
#WebMvcTest(IngestionServerApplication.class)
public class IngestionServerApplicationTests {
#Autowired
private MockMvc mockMvc;
#MockBean
private IngestionPayloadProcessor processor;
#Test
public void testIngestService() throws Exception {
given(this.processor.process(anyObject())).willReturn(new InjestionSuccessResponse());
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.add("authToken","safdafio12312asdfs23");
RequestBuilder requestBuilder = put("/ingest").content("{'testKey' : 'testVal'}").accept(MediaType.APPLICATION_JSON).headers(httpHeaders);
this.mockMvc.perform(requestBuilder).andExpect(status().isOk());
}
}
Details on the new features of Spring Boot 1.4 testing are here: https://spring.io/blog/2016/04/15/testing-improvements-in-spring-boot-1-4
* Update based on comments *
Realized you could just auto configure the MockMvc and not need to use the TestRestTemplate. I haven't tested this but it should work.
#RunWith(SpringRunner.class)
#SpringBootTest
#AutoConfigureMockMvc
public class IngestionServerApplicationTests {
#Autowired
private MockMvc mockMvc;
#Test
public void testIngestService() throws Exception {
HttpHeaders httpHeaders = new HttpHeaders();
httpHeaders.add("authToken","safdafio12312asdfs23");
RequestBuilder requestBuilder = put("/ingest").content("{'testKey' : 'testVal'}").accept(MediaType.APPLICATION_JSON).headers(httpHeaders);
this.mockMvc.perform(requestBuilder).andExpect(status().isOk());
}
}