We're slowly migrating some projects from using the legacy RestTemplate class to the new Spring 5 WebClient. As part of this, we have some existing test classes that make use of Mockito to verify that a given method will reach out to make a GET/POST/whatever to endpoint X using the template.
Given the fluent interface of the WebClient, the same mocking approach isn't really practical. I have spent some time using WireMock, which is great, but unfortunately there seems to be a bug where occasionally the WireMock tests will overrun or hang, and as such I'm considering alternatives.
Does anyone have any other suggestions for frameworks or techniques to use to verify that Spring's WebClient is making expected calls as part of SUT execution?
Spring actually uses OkHttp MockWebServer for testing of the WebClient.
Spring's Example Integration Tests
You can set up ordered mock responses or map mock responses to request details.
Approach 1 (preferred)
MockWebServer sounds like a cool approach(i.e Use WebClient for real, but mock the service it calls by using MockWebServer (okhttp)). An adapted example is:
#ExtendWith(MockitoExtension.class)
class serviceImplTest {
private ServiceImpl serviceImpl;
public static MockWebServer mockWebServer;
#BeforeAll
static void setUp() throws IOException {
mockWebServer = new MockWebServer();
mockWebServer.start();
}
#AfterAll
static void tearDown() throws IOException {
mockWebServer.shutdown();
}
#BeforeEach
void init() {
String baseUrl = String.format("http://localhost:%s", mockWebServer.getPort());
serviceImpl = new ServiceImpl(WebClient.builder(), baseUrl);
}
#Test
#DisplayName("whatever")
void methodName() {
mockWebServer.enqueue(new MockResponse().addHeader("header", "abcde123")); //MockWebServer will respond with the queued stub.
String header = serviceImpl.fetchHeader();
assertThat(header).isEqualTo("abcde123");
}
}
Approach 2
I have also tried the other approach, i.e Use Mockito to mimic the behavior of WebClient, and it's working fine. The only downside is that there is a lot of given()-willReturn(), to cater for each call in the chain(of the fluent WebClient API).
Related
I have an application that is using Spring Boot (latest version) and creating a back-end that has RESTful api's. Traditionally, I have created controllers like:
#RestController
#RequestMapping("/contacts")
public class ContactController {
#Autowired
private ContactService service;
#RequestMapping(value = "/contactId/{contactId}",
method = RequestMethod.GET, headers = "Accept=application/json")
public #ResponseBody ContactEntity getContactById(#PathVariable("contactId") long contactId) {
ContactEntity contactEntity = service.getContactById(contactId);
return contactEntity;
}
And an integrated test has always been like:
#ExtendWith(SpringExtension.class)
#SpringBootTest(classes = ServiceContextConfiguration.class)
#ComponentScan("com.tomholmes.springboot.phonebook.server")
#Transactional
#WebAppConfiguration
public class ContactControllerTest {
#Test
public void testGetContactById() throws Exception {
MockHttpServletRequestBuilder requestBuilder =
MockMvcRequestBuilders.get(BASE_URL + "/contactId/6");
this.mockMvc.perform(requestBuilder)
.andDo(print())
.andExpect(status().isOk());
}
}
This has always worked normally for years as a 'code first' api. Now, I am dealing with a contract-first API using OpenAPI 3 and a YAML file. The API is generated in the same location as before, and I would expect the test to work as it did before, but it does not.
So one resource:
[https://www.hascode.com/2018/08/testing-openapi-swagger-schema-compliance-with-java-junit-and-assertj-swagger/#API_Test]
is suggesting I use the assertj-swagger for the OpenAPI / Swagger contract testing.
Is this the only way to go? Is there no way for me to use my old traditional testing which I find extremely useful as an integrated test.
There is a third method I am also looking into:
[https://www.testcontainers.org/modules/mockserver/]
Which I am going to try also, and I am sure it will work.
I'm also wondering if there is code out there to auto-generate the Test just like there is to generate the API endpoint and the model, it would make sense if the Open API 3 also had the ability to generate the test was well.
Ultimately, I'd like to use my old way of testing if I could, but if not, then I'll try the other ways.
We had the same issue after switching to open api contract first with auto-generated controllers/delegate interfaces. The fix was to import the delegate impl in addition to the controller itself. Example:
#WebMvcTest(FeatureController.class)
#Import(FeatureDelegateImpl.class)
public class FeatureContractTest {
#Autowired
private MockMvc mvc;
#MockBean
private BusinessService businessService;
...
FeatureController is the controller generated by open-api, which typically will be in a generated-sources folder within target. FeatureDelegateImpl is our own implementation of the delegate interface, which lives in the src/main folder.
I am wanting to create/run an Integration test to assess the processes from the controller all the way to the services, as well as all the business logic in-between. However, I don't want to make an actual request that leaves the application to another microService as it is not part of the test.
I am newer to Kotlin, In Java, I know that I could pull in Mockito and call #SpyBean on the restTemplate and then I could use doReturn(restTemplate.getForObject(...) to make sure that the REST request is mocked. I could even call verify() and make sure it ran the number of times expected. Is there a way to accomplish this using kotlin, MockK, RestAssured, and MockMVC?
note: I did pull in io.rest-assured:kotlin-extensions but I didn't see the need of using it since the test runs perfectly when I don't use #SpyK
#ExtendWith(SpringExtension::class)
#SpringBootTest
#AutoConfigureMockMvc
internal class FooControllerIT() {
#Autowired
lateinit var mockMvc: MockMvc
#SpyK
#Qualifier("restTemplateTwo")
val restTemplate: RestTemplate = mockk()
val foo= Foo(Name("Test", "Testerson"))
#BeforeEach
fun setUp() = MockKAnnotations.init(this)
#Test
fun getFooTest() {
every { restTemplate.getForObject("https://www.test.com/some-endpoint", Foo::class.java) } returns Foo()
given()
.mockMvc(mockMvc)
.auth().with(csrf())
.`when`()
.get("/rest/${foo.name.first + foo.name.last}")
.then()
.log()
.all()
.statusCode(200)
// .body("", equalTo(""))
}
}
I'm attempting something perhaps misguided but please help.
I would like to test springboot controller via #WebFluxTest. However I would like to use WebClient instead of WebTestClient. How can this be done?
So far, I managed to use reflection to get ExchangeFunction out of WebTestClient and assign it to WebClient - and it works! Calls are made, controller responds - wonderful. However I don't think this is good approach. Is there a better way?
Thank you.
Ideally, you should use a WebTestClient which is more of a convenience wrapper around the WebClient. Just like the TestRestTemplate is for a RestTemplate. Both allow a request to be created and you can easily make assertions. They exist to make your test life easier.
If you really want to use a WebClient instead of a WebTestClient and do the assertions manually (which means you are probably complicating things) you can use the WebClient.Builder to create one. Spring Boot will automatically configure one and you can simply autowire it in your test and call the build method.
#SpringBootTest
public void YourTest {
#Autowired
private WebClient.Builder webClientBuilder;
#Test
public void doTest() {
WebClient webClient = webClientBuilder.build();
}
}
The same should work with #WebFluxTest as well.
Ok, after much experimentation here is a solution to test springboot controller & filters via a mocked connection - no webservice, no ports and quick test.
Unfortunately I didn't work out how to do it via #WebFluxTest and WebClient, instead MockMvc can be used to achieve desired result:
#ExtendWith(SpringExtension.class)
#Import({SomeDependencyService.class, SomeFilter.class})
#WebMvcTest(controllers = SomeController.class, excludeAutoConfiguration = SecurityAutoConfiguration.class)
#AutoConfigureMockMvc()
public class SomeControllerTest {
#MockBean
private SomeDependencyService someDependencyService;
#Autowired
private MockMvc mockMvc;
private SomeCustomizedClient subject;
#BeforeEach
public void setUp() {
subject = buildClient();
WebClient webClient = mockClientConnection();
subject.setWebClient(webClient);
}
private WebClient mockClientConnection() {
MockMvcHttpConnector mockMvcHttpConnector = new MockMvcHttpConnector(mockMvc);
WebClient webClient = WebClient.builder().clientConnector(mockMvcHttpConnector).build();
return webClient;
}
#Test
public void sample() {
when(SomeDependencyService.somePersistentOperation(any(), any())).thenReturn(new someDummyData());
SomeDeserializedObject actual = subject.someCallToControllerEndpoint("example param");
assertThat(actual.getData).isEquals("expected data");
}
}
Now it is possible to test your customized client (for example if you have internal java client that contains few important customization like security, etags, logging, de-serialization and uniform error handling) and associated controller (and filters if you #import them along) at the cost of a unit test.
You do NOT have to bring up entire service to verify the client and controller is working correctly.
I'm trying to use Springockito and spies to verify that calls were made/not made on a service method during an end-to-end test. I'm autowiring the service that the process will also get, and spy on it. Although myService instance is instrumented, verify() does not verify previous calls, but makes a call to the original method and passes a null parameter. Why is this?
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(loader = PatchedSpringockitoContextLoader.class, locations = {
"classpath:/config.xml"
})
...
#Autowired
#WrapWithSpy
private MyService myService;
...
#Before
public void setup() {
initMocks(this);
...
}
...
#Test
public void test() {
// run the process that may or may not call the service
verify(myService, never()).myMethod(any(MyParam.class));
}
What might be happening here is that your spied object uses annotations (e.g #Transactional) that requires Spring to add an AOP proxy around your spy, which causes Mockito to malfunction.
I've had the same issue as yours although I do not use Spock, and I solved it by getting a reference to the proxied mock or spy from the Spring proxy.
Check out the suggested hack in this GitHub issue report.
I am not using Spring Boot, so I wrapped the workaround code in a #BeforeClass method.
I have a Spring web server that on a request makes an external call to some third-party web API (e.g. retreive Facebook oauth token). After getting data from this call it computes a response:
#RestController
public class HelloController {
#RequestMapping("/hello_to_facebook")
public String hello_to_facebook() {
// Ask facebook about something
HttpGet httpget = new HttpGet(buildURI("https", "graph.facebook.com", "/oauth/access_token"));
String response = httpClient.execute(httpget).getEntity().toString();
// .. Do something with a response
return response;
}
}
I'm writing an integration test that checks that hitting url on my server leads to some expected result. However I want to mock the external server locally so that I don't even need internet access to test all this. What is the best way to do this?
I'm a novice in spring, this is what I have so far.
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = Application.class)
#WebAppConfiguration
#IntegrationTest({})
public class TestHelloControllerIT {
#Test
public void getHelloToFacebook() throws Exception {
String url = new URL("http://localhost:8080/hello_to_facebook").toString();
//Somehow setup facebook server mock ...
//FaceBookServerMock facebookMock = ...
RestTemplate template = new TestRestTemplate();
ResponseEntity<String> response = template.getForEntity(url, String.class);
assertThat(response.getBody(), equalTo("..."));
//Assert that facebook mock got called
//facebookMock.verify();
}
}
The actual real set up is more complicated - I'm making Facebook oauth login and all that logic is not in the controller but in various Spring Security objects. However I suspect that testing code is supposed to be the same since I'm just hitting urls and expect a response, isn't it?
After playing a bit with various scenarios, here is the one way how can one achieve what was asked with minimal interventions to the main code
Refactor your controller to use a parameter for thirdparty server address:
#RestController
public class HelloController {
#Value("${api_host}")
private String apiHost;
#RequestMapping("/hello_to_facebook")
public String hello_to_facebook() {
// Ask facebook about something
HttpGet httpget = new HttpGet(buildURI("http", this.apiHost, "/oauth/access_token"));
String response = httpClient.execute(httpget).getEntity().toString();
// .. Do something with a response
return response + "_PROCESSED";
}
}
'api_host' equals to 'graph.facebook.com' in application.properties in the src/main/resources
Create a new controller in the src/test/java folder that mocks the thirdparty server.
Override 'api_host' for testing to 'localhost'.
Here is the code for steps 2 and 3 in one file for brevity:
#RestController
class FacebookMockController {
#RequestMapping("/oauth/access_token")
public String oauthToken() {
return "TEST_TOKEN";
}
}
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = Application.class)
#WebAppConfiguration
#IntegrationTest({"api_host=localhost",})
public class TestHelloControllerIT {
#Test
public void getHelloToFacebook() throws Exception {
String url = new URL("http://localhost:8080/hello_to_facebook").toString();
RestTemplate template = new TestRestTemplate();
ResponseEntity<String> response = template.getForEntity(url, String.class);
assertThat(response.getBody(), equalTo("TEST_TOKEN_PROCESSED"));
// Assert that facebook mock got called:
// for example add flag to mock, get the mock bean, check the flag
}
}
Is there a nicer way to do this? All feedback is appreciated!
P.S. Here are some complications I encountered putting this answer into more realistic app:
Eclipse mixes test and main configuration into classpath so you might screw up your main configuration by test classes and parameters: https://issuetracker.springsource.com/browse/STS-3882 Use gradle bootRun to avoid it
You have to open access to your mocked links in the security config if you have spring security set up. To append to a security config instead of messing with a main configuration config:
#Configuration
#Order(1)
class TestWebSecurityConfig extends WebSecurityConfig {
#Override
protected void configure(HttpSecurity http) throws Exception {
http
.authorizeRequests()
.antMatchers("/oauth/access_token").permitAll();
super.configure(http);
}
}
It is not straightforward to hit https links in integration tests. I end up using TestRestTemplate with custom request factory and configured SSLConnectionSocketFactory.
If you use RestTemplate inside the HelloController you would be able to test it MockRestServiceTest, like here: https://www.baeldung.com/spring-mock-rest-template#using-spring-test
In this case
#RunWith(SpringJUnit4ClassRunner.class)
// Importand we need a working environment
#SpringBootTest(webEnvironment= SpringBootTest.WebEnvironment.RANDOM_PORT)
public class TestHelloControllerIT {
#Autowired
private RestTemplate restTemplate;
// Available by default in SpringBootTest env
#Autowired
private TestRestTemplate testRestTemplate;
#Value("${api_host}")
private String apiHost;
private MockRestServiceServer mockServer;
#Before
public void init(){
mockServer = MockRestServiceServer.createServer(this.restTemplate);
}
#Test
public void getHelloToFacebook() throws Exception {
mockServer.expect(ExpectedCount.manyTimes(),
requestTo(buildURI("http", this.apiHost, "/oauth/access_token"))))
.andExpect(method(HttpMethod.POST))
.andRespond(withStatus(HttpStatus.OK)
.contentType(MediaType.APPLICATION_JSON)
.body("{\"token\": \"TEST_TOKEN\"}")
);
// You can use relative URI thanks to TestRestTemplate
ResponseEntity<String> response = testRestTemplate.getForEntity("/hello_to_facebook", String.class);
// Do the test you need
}
}
Remember that you need a common RestTemplateConfiguration for autowiring, like this:
#Configuration
public class RestTemplateConfiguration {
/**
* A RestTemplate that compresses requests.
*
* #return RestTemplate
*/
#Bean
public RestTemplate getRestTemplate() {
return new RestTemplate();
}
}
And that you have to use it inside HelloController as well
#RestController
public class HelloController {
#Autowired
private RestTemplate restTemplate;
#RequestMapping("/hello_to_facebook")
public String hello_to_facebook() {
String response = restTemplate.getForEntity(buildURI("https", "graph.facebook.com", "/oauth/access_token"), String.class).getBody();
// .. Do something with a response
return response;
}
}
2018 Things have improved much.
I ended up using spring-cloud-contracts
Here's a video introduction https://www.youtube.com/watch?v=JEmpIDiX7LU . The first part of the talk walk you through a legacy service. That's the one you can use for external API.
Gist is,
You create a Contract for the external service using Groovy DSL or other methods that even support explicit calls/proxy or recording. Check documentation on what works for you
Since you dont actually have control over the 3rd party in this case, you will use the contract-verifier and create the stub locally but remember to skipTests
With the stub-jar now compiled and available you can run it from within your test cases as it will run a Wiremock for you.
This question and several stackoverflow answers helped me find the solution so here is my sample project for the next person who has these and other similar microservices related tests.
https://github.com/abshkd/spring-cloud-sample-games
With everything working once you will never ever look back and do all your tests with spring-cloud-contracts
#marcin-grzejszczak the author, is also on SO and he helped a lot figure this out. so if you get stuck, just post on SO.
You could have another spring configuration file that exposes the same endpoint as the HelloController class. You could then simply return the canned json response.
From your code, I'm not sure about just what you are trying to accomplish. If you simply want to see that the call to facebook works then there's no substitute for testing against the service that actually talks to facebook. Mocking the facebook response just to ensure that it is mocked correctly, doesn't strike me as a terribly useful test.
If you are testing to see that the data that comes back from facebook is mutated in some way and you want to make sure that the work being done on it is correct, then you could do that work in a separate method that took the facebook response as a paramater, and then carried out the mutation. You could then check based on various json inputs that it was working correctly.
You could test without bringing the web service into it at all.