I was wondering how should I go about injecting a mocks - we have bunch of classes that do server calls, however our CI system can not access external resources and thus will not make a call to a server. Thus, the call has to be simulated and hardcoded values (such as response codes) needed to be return.
So, here is a snippet of a code:
HttpPost httpRequest = new HttPost(uri);
//some code here
try{
httpRequest.setEntity(entity);
HttpResponse response = httpClient.execute(httpRequest);
...
//other, irrelevant, code is here
So, is it possible to inject a mock into httpClient.execute(httpRequest) and return hardcoded response entity from a test unit?
Thank you
Usually mocking some object looks like this:
public class TestClass {
private HttpServer server;
public HttpServer getServer() {
return server;
}
public void setServer(HttpServer server) {
this.server = server;
}
public void method(){
//some action with server
}
}
And test class:
public class TestClassTest {
//class under test
TestClass test = new TestClass();
#org.junit.Test
public void testMethod() throws Exception {
HttpServer mockServer = Mockito.mock(HttpServer.class);
test.setServer(mockServer);
//set up mock, test and verify
}
}
Here you some useful links:
Code example
Official documentation
Related
I have a service class that calls a REST API to get, create, update and delete subscribers. The Uri remains the same, but the HTTP method changes as you'd expect. I want to test the correct method is given. Below is an example of the updateSubscriber and its test.
public class MyService {
HttpClient httpClient;
public MyService(HttpClient httpClient) {
this.httpClient = httpClient;
}
//...
public int updateSubscriber(Subscriber subscriber) throws ... {
// PUT is the correct method for this request
HttpResponse response = httpClient.execute( new HttpPut( "https://example.org/api/subscribers" ) );
//...
}
//...
Here is my test with JUnit and Mockito:
#RunWith(MockitoJUnitRunner.class)
public class MyServiceTest
{
#Mock
private HttpClient mockHttpClient;
#Mock
private HttpResponse mockResponse;
#Mock
private StatusLine mockStatusline;
#Mock
private HttpEntity mockEntity;
// test subject
private MyService myService;
#Before
public void setup() {
// // this will just ensure http* objects are returning our mocked instances so we can manipulate them..
// when(mockHttpClient.execute(any(HttpGet.class))).thenReturn(mockResponse);
// when(mockHttpClient.execute(any(HttpPost.class))).thenReturn(mockResponse);
// when(mockHttpClient.execute(any(HttpPut.class))).thenReturn(mockResponse);
// when(mockHttpClient.execute(any(HttpDelete.class))).thenReturn(mockResponse);
// when(mockResponse.getStatusLine()).thenReturn(mockStatusline);
// when(mockStatusline.getStatusCode()).thenReturn(HttpStatus.SC_OK);
myService = new MyService(mockHttpClient);
}
#Test
public void testUpdateSubscriber() throws ...
{
when(mockHttpClient.execute(any(HttpPut.class))).thenReturn(mockResponse);
when(mockResponse.getStatusLine()).thenReturn(mockStatusline);
when(mockStatusline.getStatusCode()).thenReturn(HttpStatus.SC_OK);
String responseString = "...";
// this is consumed by a static method which we cannot mock, so we must deal with an actual entity instance
BasicHttpEntity entity = new BasicHttpEntity();
entity.setContent(new ByteArrayInputStream(responseString.getBytes()));
when(mockResponse.getEntity()).thenReturn(entity);
// create a test case Subscriber instance
Subscriber subscriber = new Subscriber();
int statusCode = myService.updateSubscriber(subscriber);
assertEquals(HttpStatus.SC_OK, statusCode);
// just confirm that an HTTP request was made
// TODO this isn't working, still passes when wrong Http* method used
verify(mockHttpClient, times(1)).execute(any(HttpPut.class));
}
//...
However, when I (wrongfully) have the another Http* method instance, it still passes:
// this is wrong, and should fail, but passed :(
HttpResponse response = httpClient.execute( new HttpGet( "https://example.org/api/subscribers" ) );
I'd really like to be able to test this as the action performed could be wrong if the method is mistaken. This test is to ensure that the PUT method was correctly used with the HTTP request for updateSubscriber. Any ideas?
Test passes because HtppPut and HttpGet both are implementation classes of HttpRequestBase, Change the mocking from HttpRequestBase class to HttpPut class
when(mockHttpClient.execute(any(HttpPut.class))).thenReturn(mockResponse);
So now if you try with GET call Test will fail with NullPointerException since GET call has no stub
Not sure if this is the proper answer to my question but I got managed to get the tests to work as intended using a custom argument matcher:
package uk.ac.strath.matchers;
import org.apache.http.client.methods.HttpUriRequest;
import org.mockito.ArgumentMatcher;
public class HttpMethodMatcher implements ArgumentMatcher<HttpUriRequest> {
private String expectedClassName;
// constructors
public HttpMethodMatcher(String expectedClassName) {
this.expectedClassName = expectedClassName;
}
#Override
public boolean matches(HttpUriRequest httpMessage) {
if (httpMessage.getClass().getName().equals(expectedClassName)) {
return true;
}
return false;
}
}
Now in my test, I can do:
verify(mockHttpClient, times(1)).execute( argThat(new HttpMethodMatcher( HttpGet.class.getName() )) );
This tutorial was helpful: https://www.baeldung.com/mockito-argument-matchers
I have the following problem: I'm using Spring-Boot for a little private web-based project and I want Spring to make a call to a webservice when it's started. And by started I mean "when my application is ready to handle requests".
I've already tried implementing the ApplicationListener<ContextRefreshedEvent> but it did not work, as the Event happend to early (i.e. before the embedded server was ready to handle request). Also the options mentioned in this question did not solve this problem.
My question now is: Is there any possibilty to tell Spring to execute something after the server has finished starting up and is ready to handle requests?
EDIT (in response to Daniel's answer):
The problem is that I need some injected properties to make that webservice call, and since injecting static values does not work in spring this approach is no option.
My listener, that does what I want, just a bit too early looks something like this:
#Component
public class StartupListener implements ApplicationListener{
#Autowired
private URLProvider urlProvider;
#Value("${server.port}")
private int port;
#Value("${project.name}")
private String projectName;
#Override
public final void onApplicationEvent(ContextRefreshedEvent event) {
RestTemplate template = new RestTemplate();
String url = uriProvider.getWebserviceUrl(this.projectName);
template.put(url, null);
}
}
SECOND EDIT:
Although this question solves a very similar problem it seems like I'm not able to inject into the object because it needs to have a constructor of the form (org.springframework.boot.SpringApplication, [Ljava.lang.String;).
Also it would be desirebale to solve it without having to create the spring.factories file but by using annotations.
If I understand what your problem is, you could call the webservice on your application main, right after it initiates.
public static void main(String[] args) {
new SpringApplication(Application.class).run(args);
//call the webservice for you to handle...
}
I'm not sure if this is what you want...
In your component you can use the #PostConstruct annotation. e.g.
#Component
public class StartupListener {
#Autowired
private URLProvider urlProvider;
#Value("${server.port}")
private int port;
#Value("${project.name}")
private String projectName;
#PostConstruct
public final void init() {
RestTemplate template = new RestTemplate();
String url = uriProvider.getWebserviceUrl(this.projectName);
template.put(url, null);
}
}
This will fire once the bean has been initialised and autowiring has taken place.
#Component
public class StartUp implements ApplicationListener<WebServerInitializedEvent> {
private WebClient webClient;
#Override
public void onApplicationEvent(WebServerInitializedEvent event) {
String baseUrl = "http://url.com"
webClient = WebClient.create(baseUrl);
executeRestCall(baseUrl+"/info");
}
void executeRestCall(String uri) {
try {
webClient.get()
.uri(uri)
.exchange()
.block();
} catch (Exception e) {
log.error("Request failed for url - {}",uri, e);
}
}}
In my integration test, I tried to use resttemplate to send a Get request to a dummy server created by MockMvcBuilders. However I got an error:
I/O error on GET request for "http://localhost:8080/test":Connection refused:
(In the function testAccess(), url is "http://localhost:8080/test"). My code is as below:
#RunWith(SpringJUnit4ClassRunner.class)
#WebAppConfiguration
#IntegrationTest("server.port=8080")
public class MyTest {
private MockMvc mockMvc = null;
#Autowired
private WebApplicationContext context;
#Value("${server.port}")
private int port;
#Autowired
private MyController myController;
#Before
public void setUp(){
mockMvc = MockMvcBuilders.webAppContextSetup(context)
.build();
}
#Test
public void testAccess() throws Exception{
RestTemplate restTemplate=new RestTemplate();
String url="http://localhost:8080/test";
try{
ResponseEntity<String> response = restTemplate.exchange(url, HttpMethod.GET, null, String.class);
}
catch(ResourceAccessException ex){
System.out.println(ex.getMessage());
}
}
#Controller
public static class MyController {
#RequestMapping(value = "/test", method = RequestMethod.GET)
public #ResponseBody String access() {
return "OK";
}
}
}
The way I've done it is this:
First, you create a mock server from the actual RestTemplate you are using in your application
#Before
public void setup() throws Exception {
mockServer = MockRestServiceServer.createServer(myService.restTemplate);
}
Then you define how that request is going to work:
mockServer.expect(requestTo("http://localhost:8080/myrestapi"))
.andExpect(method(HttpMethod.POST))
.andRespond(withSuccess("{ success: true }", MediaType.APPLICATION_JSON));
And last you call the method in your application that will trigger a call to that url with that RestTemplate:
#Test
public void testThis() throws Exception {
myService.somethingThatCallsMyRestApi(parameters);
}
That will make your tests work as if there was a server up and running to process requests.
Using this in your example makes no sense, cause you would be testing that you build your test correctly and nothing else from the actual application.
The problem with this is that you cannot test dynamic responses. I mean, in my case the method I'm calling generates different data every time you call it and then sends it to the mockServer and then validates that the response matches in some very specific way. I haven't found a solution yet, but if the data you are going to send and receive is previously known, which would be in most cases, you'll have no problem using this.
Why are you defining a controller in your Test class and then trying to test it ? It doesn't feel logical to try to test something that is defined within the test it self.
Rather you would want to test a controller defined somewhere outside your tests, an actual controller that is used within your application.
Let's say MyController is defined as an actual controller then you could use the mockMvc object you created to test it.
mockMvc.perform(get('/test'))
.andExpect(status().isOk())
How to unit test the below method with the EasyMock. I tried to mock WebResource but it is returning me a NullPointerException.
public void connect()
{
Client client = setUpClient();
WebResource jobBuilder = client.resource("URL");
String jobXml = jobBuilder.accept(MediaType.APPLICATION_XML)
.type(MediaType.APPLICATION_JSON)
.entity(request)
.post(String.class);
}
public Client setUpClient()
{
ClientConfig cc = new DefaultClientConfig();
cc.getClasses().add(JacksonJsonProvider.class);
Client client = Client.create(cc);
return client;
}
You clearly have to read up on the Inversion of Control Principle (http://en.wikipedia.org/wiki/Inversion_of_control), if not for the sake of the better designed code, then for the sake of unit testing. The client object in the method above is created inside the method itself, using the static factory method Client.create(). There is no good way to inject a mock collaborator with that approach. You should either allow injection of the client via a setter or a constructor, or delegate its creation to some sort of a factory.
If you use the 1st approach, you can inject the mock client directly via the setter or constructor during the unit test setup.
If you use the 2nd approach, you can provide a factory that would return a mock client when called.
EDIT 5/03:
Here's example of making your code testable by providing an object factory for a 3rd party library object:
public class ClassToTest {
private ClientFactory factory;
public ClassTotest() {
this(new ClientFactory());
}
public ClassToTest(ClientFactory factory) {
this.factory = factory;
}
public void connect() {
Client client = factory.getClient();
WebResource jobBuilder = client.resource("URL");
String jobXml = jobBuilder.accept(MediaType.APPLICATION_XML)
.type(MediaType.APPLICATION_JSON)
.entity(request)
.post(String.class);
}
}
public class ClientFactory() {
public Client getClient() {
ClientConfig cc = new DefaultClientConfig();
cc.getClasses().add(JacksonJsonProvider.class);
Client client = Client.create(cc);
return client;
}
}
Now, in your application code you can instantiate your class using the no-argument constructor. In the unit test you would use the other constructor. This way you would be able to inject a mock Client that you would script for the purpose of testing WebResource.
Hope this helps.
I did some TDDs before, but they were just straightforward and simple.
However, I will implement a restful client and invoke a restful API of third parties (Twitter, or Jira).
I used Resteasy client framework to implement that. The code is:
public void invokePUT() {
ClientRequest request =
new ClientRequest("http://example.com/customers");
request.accept("application/xml");
ClientResponse<Customer> response = request.put(Customer.class);
try {
if (response.getStatus() != 201)
throw new RuntimeException("Failed!");
} finally {
response.releaseConnection();
}}
If I want to write a test for this method (should write test before implement this method), what kind of the code should I write.
For GET, I can test the return Entity is equals to my expected entity and for POST, I can test the created entity's id is not null.
But how about for PUT and DELETE. Thanks.
Try to use REST Assured testing framework. It is great tool for testing REST services. On their website you'll find tons of examples how to use it. Just use it together with JUnit or TestNG to check assertions and you are done.
Here's how I'd go about the problem in the short term:
1) Extract the request into a parameter to the method. invokePUT() now becomes:
public void invokePUT(ClientRequest request) {
request.accept("application/xml");
ClientResponse<Customer> response = request.put(Customer.class);
try {
if (response.getStatus() != 201)
throw new RuntimeException("Failed!");
} finally {
response.releaseConnection();
}
}
2) In your test, use a stubbed version of ClientRequest
#Test
public void sendsPayloadAsXml() {
StubbedClientRequest request = new StubbedClientRequest(new StubbedResponse());
restApi.invokePUT(request);
assertEquals("application/xml", request.acceptHeader);
}
#Test
public void makesTheCallUsingPut() {
StubbedClientRequest request = new StubbedClientRequest(new StubbedResponse());
restApi.invokePUT(request);
assertTrue(request.putWasCalled);
}
#Test
public void releasesTheConnectionWhenComplete() {
StubbedResponse success = new StubbedResponse();
StubbedClientRequest request = new StubbedClientRequest(success);
restApi.invokePUT(request);
assertTrue(success.connectionWasClosed);
}
#Test(expected = RuntimeException.class)
public void raisesAnExceptionWhenInvalidResponseReceived() {
StubbedClientRequest request = new StubbedClientRequest(new StubbedResponse(400));
restApi.invokePUT(request);
}
private static class StubbedClientRequest extends ClientRequest {
public String acceptHeader = "";
public boolean putWasCalled;
public ClientResponse response
public StubbedRequest(ClientResponse response) {
this.response = response;
}
#Override
public ClientResponse put(Class klass) {
putWasCalled = true;
return response;
}
#Override
public void accept(String header) {
acceptHeader += header;
}
}
private static class StubbedResponse extends ClientResponse {
public boolean connectionWasReleased;
public int status = 201;
public StubbedResponse(int status) {
this.status = status;
}
public StubbedResponse() { }
}
This may not be a perfect design (Handing the ClientRequest to the class and having the RestEasy stuff exposed to the outside world) but it's a start.
Hope that helps!
Brandon
i would inject mocked classes that test, if put and delete was called as intended (with expected parameters and so on). easymock or similar is good for that
(same with post and get)
EDIT:
in case you want to test the rest client, use dependency injection to inject the request, then use easymock to mock it like this (for example to test, if delete is called properly):
#Test void myTest(){
ClientRequest mock = EasyMock.createMock(ClientRequest.class);
mock.delete(2); //test if resource with id=2 is deleted or something similar
EasyMock.replay(mock);
invokeDelete(mock);
EasyMock.verify(mock);
}