How to test spring rest operation exchange - spring

Question

I have a problem with test of my method which use RestOperation exchange method. When i'm trying to mock response i get an error:
ResponseEntity cannot be returned by toString()
toString() should return String
***
If you're unsure why you're getting above error read on.
Due to the nature of the syntax above problem might occur because:
1. This exception *might* occur in wrongly written multi-threaded tests.
Please refer to Mockito FAQ on limitations of concurrency testing.
2. A spy is stubbed using when(spy.foo()).then() syntax. It is safer to stub spies -
- with doReturn|Throw() family of methods. More in javadocs for Mockito.spy() method.
org.mockito.exceptions.misusing.WrongTypeOfReturnValue:
Below is my class, which i want to test
#Component
public class AuthGateway {
#Autowired
AuthorizedHttpEntityFactory authorizedHttpEntityFactory;
#Autowired
RestOperations restOperations;
#Value("${authServer.host}:${authServer.port}/${authServer.validateToken.path}")
private String authPath;
#Value("${authServer.host}:${authServer.port}/basic/check")
private String basicAuthPath;
#Value("${authServer.tokenName}")
private String tokenName;
#Value("${authServer.host}:${authServer.port}/user")
private String userProfileUrl;
#Value("${authServer.host}:${authServer.port}/homeowner")
private String homeownerUrl;
public UnpackedToken authenticate(String token) throws ResourceAccessException, AuthException {
MultiValueMap<String, String> formData = new LinkedMultiValueMap<>();
formData.add(tokenName, token);
HttpEntity httpEntity = authorizedHttpEntityFactory.getAuthorizedHttpEntity(formData);
Map map = null;
try {
ResponseEntity<Map> entity = restOperations.exchange(authPath, HttpMethod.POST,
httpEntity, Map.class);
map = entity.getBody();
} catch (RestClientException e) {
processError(e);
}
#SuppressWarnings("unchecked")
Map<String, Object> result = map;
return new UnpackedToken(result);
}
and Test class
#RunWith(MockitoJUnitRunner.class)
public class AuthGatewayTest {
private ResponseEntity<Map> entity;
#Mock
private RestOperations restOperations;
#Mock
private LinkedMultiValueMap linkedMultiValueMap;
#Mock
private AuthorizedHttpEntityFactory authorizedHttpEntityFactory;
#Autowired
#InjectMocks
private AuthGateway authGateway;
private String token;
private Integer userId = 1;
private String role = "ROLE_PRO";
private UnpackedToken unpackedToken;
private Map<String, Object> map;
private RestClientException restClientException;
private AuthException authException;
#Before
public void setUp() throws Exception {
MockitoAnnotations.initMocks(this);
restClientException = new RestClientException("Test exception");
authException = new AuthException("Test exception");
token = "token-token";
map = new HashMap<>();
map.put("UserId", userId);
map.put("authorities", Collections.singletonList(role));
entity = new ResponseEntity<>(map, HttpStatus.OK);
unpackedToken = new UnpackedToken(map);
}
#Test
public void testAuthenticateSuccessfully() throws Exception {
HttpEntity httpEntity = new HttpEntity("body");
Mockito.when(authorizedHttpEntityFactory.getAuthorizedHttpEntity(any(Map.class))).thenReturn(httpEntity);
Mockito.when(restOperations.exchange(
Mockito.anyString(), Mockito.<HttpMethod>any(), Mockito.<HttpEntity<?>>any(), Mockito.<Class<Map>>any())).
thenReturn(entity);
Mockito.doNothing().when(linkedMultiValueMap).add(any(), any());
assertEquals(this.unpackedToken, authGateway.authenticate(token));
}
What is wrong with this mock?

Answer 1

Weird, when i change mock line into:
Mockito.when(restOperations.exchange(
Mockito.anyString(), Mockito.<HttpMethod>any(), Mockito.<HttpEntity<?>>any(), Mockito.<Class<Map>>any())).
thenReturn(new ResponseEntity<>(map, HttpStatus.OK));
then it starts working properly...