Spring Boot - Test - Validator: Invalid target for Validator - spring

Question

I'm getting the following error when I'm trying to run a test:
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.IllegalStateException: Invalid target for Validator [userCreateFormValidator bean]: com.ar.empresa.forms.UserCreateForm#15c3585
Caused by: java.lang.IllegalStateException: Invalid target for Validator [userCreateFormValidator bean]: com.ar.empresa.forms.UserCreateForm#15c3585
at org.springframework.validation.DataBinder.assertValidators(DataBinder.java:567)
at org.springframework.validation.DataBinder.addValidators(DataBinder.java:578)
at com.ar.empresa.controllers.UserController.initBinder(UserController.java:36)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
The code is:
Controller:
#Controller
public class UserController {
private UserService userService;
private UserCreateFormValidator userCreateFormValidator;
#Autowired
public UserController(UserService userService, UserCreateFormValidator userCreateFormValidator) {
this.userService = userService;
this.userCreateFormValidator = userCreateFormValidator;
}
#InitBinder("form")
public void initBinder(WebDataBinder binder) {
binder.addValidators(userCreateFormValidator);
}
#PreAuthorize("hasAuthority('ADMIN')")
#RequestMapping(value = "/user/create", method = RequestMethod.GET)
public ModelAndView getUserCreatePage() {
return new ModelAndView("user_create", "form", new UserCreateForm());
}
#PreAuthorize("hasAuthority('ADMIN')")
#RequestMapping(value = "/user/create", method = RequestMethod.POST)
public String handleUserCreateForm(#Valid #ModelAttribute("form") UserCreateForm form, BindingResult bindingResult) {
if (bindingResult.hasErrors()) {
return "user_create";
}
try {
userService.create(form);
} catch (DataIntegrityViolationException e) {
bindingResult.reject("email.exists", "Email already exists");
return "user_create";
}
return "redirect:/users";
}
}
Validator:
#Component
public class UserCreateFormValidator implements Validator {
private final UserService userService;
#Autowired
public UserCreateFormValidator(UserService userService) {
this.userService = userService;
}
#Override
public boolean supports(Class<?> clazz) {
return clazz.equals(UserCreateForm.class);
}
#Override
public void validate(Object target, Errors errors) {
UserCreateForm form = (UserCreateForm) target;
validatePasswords(errors, form);
validateEmail(errors, form);
}
private void validatePasswords(Errors errors, UserCreateForm form) {
if (!form.getPassword().equals(form.getPasswordRepeated())) {
errors.reject("password.no_match", "Passwords do not match");
}
}
private void validateEmail(Errors errors, UserCreateForm form) {
if (userService.getUserByEmail(form.getEmail()).isPresent()) {
errors.reject("email.exists", "User with this email already exists");
}
}
}
UserCreateForm:
public class UserCreateForm {
#NotEmpty
private String email = "";
#NotEmpty
private String password = "";
#NotEmpty
private String passwordRepeated = "";
#NotNull
private Role role = Role.USER;
public String getEmail() {
return email;
}
public String getPassword() {
return password;
}
public String getPasswordRepeated() {
return passwordRepeated;
}
public Role getRole() {
return role;
}
public void setEmail(String email) {
this.email = email;
}
public void setPassword(String password) {
this.password = password;
}
public void setPasswordRepeated(String passwordRepeated) {
this.passwordRepeated = passwordRepeated;
}
public void setRole(Role role) {
this.role = role;
}
}
Test:
#RunWith(SpringRunner.class)
#SpringBootTest
public class UserControllerTest {
private MockMvc mockMvc;
private MediaType contentType = new MediaType(APPLICATION_JSON.getType(),
APPLICATION_JSON.getSubtype(),
Charset.forName("utf8"));
#MockBean
private UserService userService;
#MockBean
private UserCreateFormValidator userCreateFormValidator;
#Autowired
FilterChainProxy springSecurityFilterChain;
#Before
public void setup() {
this.mockMvc = MockMvcBuilders.standaloneSetup(new UserController(userService,userCreateFormValidator)).apply(SecurityMockMvcConfigurers.springSecurity(springSecurityFilterChain)).build();
}
#Test
#WithMockUser(username="user",
password="password",
roles="ADMIN")
public void homePage_authenticatedUser() throws Exception {
mockMvc.perform(get("/user/create"))
.andExpect(status().isOk())
.andExpect(view().name("user_create"));
}
}
I don't know why, because it is a GET method, so it don't have to validate it.
Thanks! :)

Answer 1

You got this exception because you didn't mock the behaviour of public boolean supports(Class<?> clazz) method on your userCreateFormValidator #Mockbean.
If you take a look at the code of org.springframework.validation.DataBinder.assertValidators(DataBinder.java) from the log you posted, you can find there how the validators are processed and how java.lang.IllegalStateException is thrown. In Spring 4.3.8, it looks like this
if(validator != null && this.getTarget() != null && !validator.supports(this.getTarget().getClass())) {
throw new IllegalStateException("Invalid target for Validator [" + validator + "]: " + this.getTarget());
}
You didn't mock supports method of the validator and returns false by default, causing Spring code above throw the IllegalStateException.
TLDR, just give me solution:
You have to mock supports method on your validator. Add following to #Before or #BeforeClass method.
when(requestValidatorMock.supports(any())).thenReturn(true);

Answer 2

I cant comment on the correct answer but his solution worked:
Here is what I had to do for this exact error.
//Imports
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.when;
#MockBean
ApiValidationRouter apiValidationRouter;
#Before
public void beforeClass() throws Exception {
when(apiValidationRouter.supports(any())).thenReturn(true);
}