How to mock POST parameters and Model attributes? - spring

Question

I'm using Spring MVC Framework and I want to test my Controllers with JUnit. How should I mock POST or GET parameters of a Controller and how will I access the Model's attributes to check its content? My Controller's signature is the following:
#RequestMapping(value="/findings", method=RequestMethod.POST)
public String findUsers(#RequestParam("userInput") String userInput, Model m)

Answer 1

You can use spring-test and mockito alongside junit to accomplish the task.
spring-test enables you to test controllers and a whole bunch of other things in spring
mockito is a great library for creating mocked classes
This is a very high level overview of unit testing a controller. This may not be correct for your situation, but should give you a bit of a starting point.
public class SomeControllerTest {
private SomeController controller;
#Mock
private View view;
private MockMvc mockMvc;
#Before
public void setup(){
MockitoAnnotations.initMocks(this);
mockMvc = MockMvcBuilders
.standaloneSetup(controller)
.setSingleView(view)
.build();
}
#Test
public void test() throws Exception {
ObjectMapper mapper = new ObjectMapper();
Model m = new Model();
MvcResult mvcResult = mockMvc.perform(post("/findings")
.contentType(MediaType.APPLICATION_JSON)
.content(objectMapper.writeValueAsString(m)))
.andExpect(status().isOK())
.andReturn();
}
}

Answer 2

For doing that I would recomend you a simple test where you instanciate your Controller (you can mock all the dependencies) and after that you call your method pasing Model.
public class MyController (){
MyDependencyOne one;
MyDependencyTwo two ;
#Autowired
public MyController (MyDependencyOne one, MyDependencyTwo two){
this.one = one;
this.two = two;
}
public String findUsers(#RequestParam("userInput") String userInput, Model
m){
// do whatever
}
}
public class MyControllerTest (){
#Test
public void myTest(){
//MOCK your dependencies
MyController controller = new MyController(one, two);
Model model = new ExtendedModelMap()
controller.filter(model);
assertEquals("yourAtribute", model.asMap().get("yourAtribute");
}
}