【转】玩转单元测试之 Testing Spring MVC Controllers
The Spring MVC Test framework provides first class JUnit support for testing client and server-side Spring MVC code through a fluent API. Typically it loads the actual Spring configuration through theTestContext framework and always uses the DispatcherServlet to process requests thus approximating full integration tests without requiring a running Servlet container.
Spring MVC 测试框架本来是一个独立的项目，由于发展的很好，早已合并到Spring Framework 3.2 里了，测试框架提供了很好的API来测试客户端和服务端的Spring MVC代码， 本文以两个例子讲述了服务端的测试，闲话少说，让我们边看例子边学习。
目录
Getting Ready
Example
Reference Class
Unit Test
Integration Testing
总结
Troubleshooting
参考Getting Ready
测试相关Maven dependency如下:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>4.0.3.RELEASE</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mockito</groupId>
<artifactId>mockito-all</artifactId>
<version>1.9.5</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency> <dependency>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-core</artifactId>
<version>1.3</version>
<scope>test</scope>
</dependency>
关于Spring项目的一些依赖如（spring-context, spring-web, spring-webmvc, spring-beans），这里就不列举了
Example
Reference Class
Controller 如下：
@Controller
@RequestMapping("/")
public class DemoController {
@Autowired
private TestProjectService testProjectService;
@RequestMapping(value = "jsonCompare", method = RequestMethod.POST)
@ResponseBody
public List<FieldComparisonFailure> jsonCompare(@RequestParam("expect") String expect, @RequestParam("actual") String actual, ModelMap model,
HttpSession session) {
List<FieldComparisonFailure> list = testProjectService.compare(expect, actual);
return list;
}
}FieldComparisonFailure类如下
/**
* Models a failure when comparing two fields.
*/
public class FieldComparisonFailure {
private final String field;
private final Object expected;
private final Object actual;
public FieldComparisonFailure(String field, Object expected, Object actual) {
this.field = field;
this.expected = expected;
this.actual = actual;
}
public String getField() {
return field;
}
public Object getExpected() {
return expected;
}
public Object getActual() {
return actual;
}
}TestProjectService接口如下：
public interface TestProjectService {
public List<FieldComparisonFailure> compare(String expect, String actual);
}TestProjectServiceImpl 具体实现是比较两个Json字符串 返回一个List
@Service
public class TestProjectServiceImpl implements TestProjectService {
@Override
public List<FieldComparisonFailure> compare(String expect, String actual) {
Comparator comparator = new Comparator();
List<FieldComparisonFailure> list = new ArrayList<FieldComparisonFailure>();
try {
list = comparator.compare(expect, actual);
} catch (JSONException e) {
e.printStackTrace();
}
return list;
}
}##转载注明出处：http://www.cnblogs.com/wade-xu/p/4311657.html
Unit Test
首先来看一个独立的单元测试方式， 这个例子用Mockito 模拟service层以便隔离controller的测试。
package com.wadeshop.controller;
import static org.mockito.Mockito.when;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.verifyNoMoreInteractions;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.hamcrest.Matchers.hasSize;
import org.junit.Before;
import org.junit.Test;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import org.springframework.http.MediaType;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import com.google.common.collect.ImmutableList;
import com.wadeshop.service.TestProjectService;
import com.wadeshop.entity.FieldComparisonFailure;
public class DemoControllerTest_mock {
@Mock
private TestProjectService testProjectService;
@InjectMocks
private DemoController demoController;
private MockMvc mockMvc;
@Before
public void setup() {
// initialize mock object
MockitoAnnotations.initMocks(this);
// Setup Spring test in standalone mode
this.mockMvc = MockMvcBuilders.standaloneSetup(demoController).build();
}
@Test
public void test() throws Exception {
//prepare test data
FieldComparisonFailure e1 = new FieldComparisonFailure("Number", "3", "4");
FieldComparisonFailure e2 = new FieldComparisonFailure("Number", "1", "2");
//actually parameter haven't use, service was mocked
String expect = "";
String actual = "";
//Sets a return value to be returned when the method is called
when(testProjectService.compare(expect, actual)).thenReturn(ImmutableList.of(e1, e2));
//construct http request and expect response
this.mockMvc
.perform(post("/jsonCompare")
.accept(MediaType.APPLICATION_JSON)
.param("actual", actual)
.param("expect", expect))
.andDo(print()) //print request and response to Console
.andExpect(status().isOk())
.andExpect(content().contentType("application/json;charset=UTF-8"))
.andExpect(jsonPath("$", hasSize(2)))
.andExpect(jsonPath("$[0].field").value("Number"))
.andExpect(jsonPath("$[0].expected").value("3"))
.andExpect(jsonPath("$[0].actual").value("4"))
.andExpect(jsonPath("$[1].field").value("Number"))
.andExpect(jsonPath("$[1].expected").value("1"))
.andExpect(jsonPath("$[1].actual").value("2"));
//verify Interactions with any mock
verify(testProjectService, times(1)).compare(expect, actual);
verifyNoMoreInteractions(testProjectService);
}
}@Mock: 需要被Mock的对象
@InjectMocks: 需要将Mock对象注入的对象, 此处就是Controller
Before test
初始化Mock对象， 通过MockMvcBuilders.standaloneSetup模拟一个Mvc测试环境，注入controller, 通过build得到一个MockMvc， 后面就用MockMvc的一些API做测试。
这不是真实的Spring MVC环境，如果要模拟真实环境需要用 MockMvcBuilders.webAppContextSetup(webApplicationContext).build()， 见下文。
测试方法里面需要构建测试数据，mock service调用方法，返回一个ImmutableList （google-collections 谷歌的集合库）
然后构造http请求并且传入参数执行， 最后断言验证期望结果， 关于JsonPath的使用请参考http://goessner.net/articles/JsonPath/
运行
andDo(print()) 打印到控制台的信息如下
MockHttpServletRequest:
HTTP Method = POST
Request URI = /jsonCompare
Parameters = {actual=[], expect=[]}
Headers = {Accept=[application/json]}
Handler:
Type = com.wadeshop.controller.DemoController
Async:
Was async started = false
Async result = null
Resolved Exception:
Type = null
ModelAndView:
View name = null
View = null
Model = null
FlashMap:
MockHttpServletResponse:
Status = 200
Error message = null
Headers = {Content-Type=[application/json;charset=UTF-8]}
Content type = application/json;charset=UTF-8
Body = [{"field":"Number","actual":"4","expected":"3"},{"field":"Number","actual":"2","expected":"1"}]
Forwarded URL = null
Redirected URL = null
Cookies = []##转载注明出处：http://www.cnblogs.com/wade-xu/p/4311657.html
Integration Testing
再来看集成Web环境方式， 这次仍然使用Spring MVC Test 但还需要加载 WebApplicationContext
import static org.hamcrest.Matchers.hasSize;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;
@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration(value = "src/main/webapp")
@ContextConfiguration("file:src/main/resources/applicationContext.xml")
public class DemoControllerTest {
@Autowired
private WebApplicationContext wac;
private MockMvc mockMvc;
@Before
public void setUp() {
mockMvc = MockMvcBuilders.webAppContextSetup(wac).build();
}
@Test
public void test() throws Exception {
String actual = "{\"orderNumber\": \"4955\",\"orderVersion\": \"1\"}";
String expect = "{\"orderNumber\": \"4956\",\"orderVersion\": \"1\"}";
this.mockMvc
.perform(post("/jsonCompare")
.accept(MediaType.APPLICATION_JSON)
.param("actual", actual)
.param("expect", expect))
.andDo(print())
.andExpect(status().isOk())
.andExpect(content().contentType("application/json"))
.andExpect(jsonPath("$", hasSize(1)))
.andExpect(jsonPath("$[0].field").value("orderNumber"))
.andExpect(jsonPath("$[0].actual").value("4955"))
.andExpect(jsonPath("$[0].expected").value("4956"));
}
}@RunWith: 告诉Junit使用 Spring-Test 框架, 允许加载web 应用程序上下文。
@WebAppConfiguration: 表明该类会使用web应用程序的默认根目录来载入ApplicationContext, value = "src/main/webapp" 可以不填，默认此目录
@ContextConfiguration： 指定需要加载的spring配置文件的地址 ("file:src/main/resources/applicationContext.xml")
@Autowired WebApplicationContext wac：注入web环境的ApplicationContext容器；
使用MockMvcBuilders.webAppContextSetup(wac).build()来创建一个MockMvc进行测试, 此为模拟真实的Spring MVC环境
测试过程和前面一个例子大体相似，唯一的区别就是，这次传入的是真实的参数，调用真实的service取得返回值。
运行时间比较长
控制台信息
MockHttpServletRequest:
HTTP Method = POST
Request URI = /jsonCompare
Parameters = {actual=[{"orderNumber": "4955","orderVersion": "1"}], expect=[{"orderNumber": "4956","orderVersion": "1"}]}
Headers = {Accept=[application/json]}
Handler:
Type = com.wadeshop.controller.DemoController
Async:
Was async started = false
Async result = null
Resolved Exception:
Type = null
ModelAndView:
View name = null
View = null
Model = null
FlashMap:
MockHttpServletResponse:
Status = 200
Error message = null
Headers = {Content-Type=[application/json]}
Content type = application/json
Body = [{"field":"orderNumber","actual":"4955","expected":"4956"}]
Forwarded URL = null
Redirected URL = null
Cookies = []从上面的例子来看集成测试Spring MVC controller是不是也很简单， 稍微配置一下就行了。
##转载注明出处：http://www.cnblogs.com/wade-xu/p/4311657.html
总结
单元测试过程无非就这三部曲：
- 准备 （测试环境，测试数据）
- 执行 （构造请求传入参数执行）
- 断言 （验证结果）
Troubleshooting
如果发现一些NoClassDefFoundError， 估计依赖的jar版本太旧了。
import 哪些类不要弄错了，有些需要static import, IDE工具不一定会提示导入
参考