How to write proper JUnit test case rest controllers - junit

Question

I want to write JUnit test case rest controller using mockito framework. I want to know how to write test cases for http request like get and post. Also how to test api which uploads a document.

Answer 1

import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.anyBoolean;
import static org.mockito.ArgumentMatchers.anyString;
import static org.mockito.Mockito.doNothing;
import static org.mockito.Mockito.when;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.fileUpload;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
#RunWith(MockitoJUnitRunner.class)
#WebMvcTest
#AutoConfigureMockMvc
public class ControllerTest {
#Autowired
private MockMvc mvc;
#Mock
Service service;
#InjectMocks
private Controller controller;
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
mvc = MockMvcBuilders.standaloneSetup(marketplaceCatalogController)
.setCustomArgumentResolvers(new PageableHandlerMethodArgumentResolver())
.setViewResolvers(new ViewResolver() {
#Override
public View resolveViewName(String viewName, Locale locale) throws Exception {
return new MappingJackson2JsonView();
}
}).build();
}
#Test
public void testGetMethod() throws Exception {
when(service.getMethod(Mockito.any(SomeClass.class))).thenReturn(new SomeOtherClass);
doNothing().when(service).someMethod();
mvc.perform(get("/get-method").param("paramKey",
"paramValue")).andExpect(status().isOk()).andDo(print());
}
#Test
public void testStatusTnC() throws Exception {
String payload = "{\"key1\": \"value1\", \"key2\": \"value2\"}";
mvc.perform(post("/post-method").content(payload)).andExpect(status().isOk()).andDo(print());
}
#Test
public void testUploadFile() throws Exception {
when(service.uploadSomeContent(any(), any(), anyString(), anyString())).thenReturn(new SomeClass());
mvc.perform(fileUpload("/post-request/uploadFile").file("somefile", "Hello, World!".getBytes()).param("param1", "value1").contentType(MediaType.MULTIPART_FORM_DATA)).andExpect(status().isOk()).andDo(print());
}
}