Spring Boot 简明教程

Spring Boot - Rest Controller Unit Test

Spring Boot 提供了一种便捷的方式来针对 Rest Controller 文件编写单元测试。借助于 SpringJUnit4ClassRunner 和 MockMvc，我们可以创建一个 Web 应用程序上下文来针对 Rest Controller 文件编写单元测试。

Spring Boot provides an easy way to write a Unit Test for Rest Controller file. With the help of SpringJUnit4ClassRunner and MockMvc, we can create a web application context to write Unit Test for Rest Controller file.

单元测试应该编写在 src/test/java 目录下，用于编写测试的类路径资源应该放在 src/test/resources 目录下。

Unit Tests should be written under the src/test/java directory and classpath resources for writing a test should be placed under the src/test/resources directory.

要编写一个单元测试，我们需要在构建配置文件中添加 Spring Boot Starter 测试依赖，如下所示。

For Writing a Unit Test, we need to add the Spring Boot Starter Test dependency in your build configuration file as shown below.

<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-test</artifactId>
   <scope>test</scope>
</dependency>

Gradle 用户可以在 build.gradle 文件中添加以下依赖项。

Gradle users can add the following dependency in your build.gradle file.

testCompile('org.springframework.boot:spring-boot-starter-test')

在编写测试用例之前，我们应该首先构建 RESTful Web 服务。有关构建 RESTful Web 服务的更多信息，请参阅本教程中给出的相同章节。

Before writing a Test case, we should first build RESTful web services. For further information on building RESTful web services, please refer to the chapter on the same given in this tutorial.

Writing a Unit Test for REST Controller

在本节中，让我们看看如何编写 REST 控制器的单元测试。

In this section, let us see how to write a Unit Test for the REST Controller.

首先，我们需要创建一个用于通过 MockMvc 创建 Web 应用程序上下文的抽象类文件，并定义 mapToJson() 和 mapFromJson() 方法，以将 Java 对象转换成 JSON 字符串，并将 JSON 字符串转换成 Java 对象。

First, we need to create Abstract class file used to create web application context by using MockMvc and define the mapToJson() and mapFromJson() methods to convert the Java object into JSON string and convert the JSON string into Java object.

package com.tutorialspoint.demo;

import java.io.IOException;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
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;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest(classes = DemoApplication.class)
@WebAppConfiguration
public abstract class AbstractTest {
   protected MockMvc mvc;
   @Autowired
   WebApplicationContext webApplicationContext;

   protected void setUp() {
      mvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
   }
   protected String mapToJson(Object obj) throws JsonProcessingException {
      ObjectMapper objectMapper = new ObjectMapper();
      return objectMapper.writeValueAsString(obj);
   }
   protected <T> T mapFromJson(String json, Class<T> clazz)
      throws JsonParseException, JsonMappingException, IOException {

      ObjectMapper objectMapper = new ObjectMapper();
      return objectMapper.readValue(json, clazz);
   }
}

接下来，编写一个扩展 AbstractTest 类的类文件，并为每个 GET、POST、PUT 和 DELETE 方法编写一个单元测试。

Next, write a class file that extends the AbstractTest class and write a Unit Test for each method such GET, POST, PUT and DELETE.

下面给出了 GET API 测试用例的代码。此 API 用于查看产品列表。

The code for GET API Test case is given below. This API is to view the list of products.

@Test
public void getProductsList() throws Exception {
   String uri = "/products";
   MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.get(uri)
      .accept(MediaType.APPLICATION_JSON_VALUE)).andReturn();

   int status = mvcResult.getResponse().getStatus();
   assertEquals(200, status);
   String content = mvcResult.getResponse().getContentAsString();
   Product[] productlist = super.mapFromJson(content, Product[].class);
   assertTrue(productlist.length > 0);
}

下面给出了 POST API 测试用例的代码。此 API 用于创建产品。

The code for POST API test case is given below. This API is to create a product.

@Test
public void createProduct() throws Exception {
   String uri = "/products";
   Product product = new Product();
   product.setId("3");
   product.setName("Ginger");

   String inputJson = super.mapToJson(product);
   MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.post(uri)
      .contentType(MediaType.APPLICATION_JSON_VALUE).content(inputJson)).andReturn();

   int status = mvcResult.getResponse().getStatus();
   assertEquals(201, status);
   String content = mvcResult.getResponse().getContentAsString();
   assertEquals(content, "Product is created successfully");
}

下面给出了 PUT API 测试用例的代码。此 API 用于更新现有产品。

The code for PUT API Test case is given below. This API is to update the existing product.

@Test
public void updateProduct() throws Exception {
   String uri = "/products/2";
   Product product = new Product();
   product.setName("Lemon");

   String inputJson = super.mapToJson(product);
   MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.put(uri)
      .contentType(MediaType.APPLICATION_JSON_VALUE).content(inputJson)).andReturn();

   int status = mvcResult.getResponse().getStatus();
   assertEquals(200, status);
   String content = mvcResult.getResponse().getContentAsString();
   assertEquals(content, "Product is updated successsfully");
}

下面给出了 DELETE API 测试用例的代码。此 API 将删除现有产品。

The code for Delete API Test case is given below. This API will delete the existing product.

@Test
public void deleteProduct() throws Exception {
   String uri = "/products/2";
   MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.delete(uri)).andReturn();
   int status = mvcResult.getResponse().getStatus();
   assertEquals(200, status);
   String content = mvcResult.getResponse().getContentAsString();
   assertEquals(content, "Product is deleted successsfully");
}

下面给出了完整的控制器测试类文件 −

The full Controller Test class file is given below −

package com.tutorialspoint.demo;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

import org.junit.Before;
import org.junit.Test;
import org.springframework.http.MediaType;
import org.springframework.test.web.servlet.MvcResult;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;

import com.tutorialspoint.demo.model.Product;

public class ProductServiceControllerTest extends AbstractTest {
   @Override
   @Before
   public void setUp() {
      super.setUp();
   }
   @Test
   public void getProductsList() throws Exception {
      String uri = "/products";
      MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.get(uri)
         .accept(MediaType.APPLICATION_JSON_VALUE)).andReturn();

      int status = mvcResult.getResponse().getStatus();
      assertEquals(200, status);
      String content = mvcResult.getResponse().getContentAsString();
      Product[] productlist = super.mapFromJson(content, Product[].class);
      assertTrue(productlist.length > 0);
   }
   @Test
   public void createProduct() throws Exception {
      String uri = "/products";
      Product product = new Product();
      product.setId("3");
      product.setName("Ginger");
      String inputJson = super.mapToJson(product);
      MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.post(uri)
         .contentType(MediaType.APPLICATION_JSON_VALUE)
         .content(inputJson)).andReturn();

      int status = mvcResult.getResponse().getStatus();
      assertEquals(201, status);
      String content = mvcResult.getResponse().getContentAsString();
      assertEquals(content, "Product is created successfully");
   }
   @Test
   public void updateProduct() throws Exception {
      String uri = "/products/2";
      Product product = new Product();
      product.setName("Lemon");
      String inputJson = super.mapToJson(product);
      MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.put(uri)
         .contentType(MediaType.APPLICATION_JSON_VALUE)
         .content(inputJson)).andReturn();

      int status = mvcResult.getResponse().getStatus();
      assertEquals(200, status);
      String content = mvcResult.getResponse().getContentAsString();
      assertEquals(content, "Product is updated successsfully");
   }
   @Test
   public void deleteProduct() throws Exception {
      String uri = "/products/2";
      MvcResult mvcResult = mvc.perform(MockMvcRequestBuilders.delete(uri)).andReturn();
      int status = mvcResult.getResponse().getStatus();
      assertEquals(200, status);
      String content = mvcResult.getResponse().getContentAsString();
      assertEquals(content, "Product is deleted successsfully");
   }
}

你可以创建一个可执行 JAR 文件，并使用下面给出的 Maven 或 Gradle 命令运行 Spring Boot 应用程序：

You can create an executable JAR file, and run the Spring Boot application by using the Maven or Gradle commands given below −

对于 Maven，你可以使用下面给出的命令 −

For Maven, you can use the command given below −

mvn clean install

现在，你可以在控制台窗口中查看测试结果。

Now, you can see the test results in console window.

对于 Gradle，你可以使用如下所示的命令：

For Gradle, you can use the command as shown below −

gradle clean build

你可以在控制台窗口中查看 rest 结果，如下所示。

You can see the rest results in console window as shown below.