WireMock 教程

2. Maven 依赖

要在项目中使用 WireMock，需要在 POM 文件中添加以下依赖：

<dependency>
    <groupId>org.wiremock</groupId>
    <artifactId>wiremock</artifactId>
    <version>3.3.1</version>
    <scope>test</scope>
</dependency>

3. 手动管理服务器

本节介绍如何手动配置 WireMock 服务器（不依赖 JUnit 自动配置），通过一个简单存根演示基本用法。

3.1. 服务器设置

首先创建 WireMock 服务器实例：

WireMockServer wireMockServer = new WireMockServer(String host, int port);

若不提供参数：

• 主机默认为 localhost
• 端口默认为 8080

通过以下方法控制服务器生命周期：

wireMockServer.start(); // 启动服务器

wireMockServer.stop(); // 停止服务器

3.2. 基础用法

演示一个最简单的存根配置（精确匹配 URL）：

1. 创建服务器实例：

   WireMockServer wireMockServer = new WireMockServer();
   

2. 启动服务器（客户端连接前必须启动）：

   wireMockServer.start();
   

3. 配置存根：

   configureFor("localhost", 8080);
   stubFor(get(urlEqualTo("/baeldung"))
       .willReturn(aResponse()
           .withBody("Welcome to Baeldung!")));
   

4. 创建 HTTP 客户端（使用 Apache HttpClient）：

   CloseableHttpClient httpClient = HttpClients.createDefault();
   

5. 执行请求并获取响应：

   HttpGet request = new HttpGet("http://localhost:8080/baeldung");
   HttpResponse httpResponse = httpClient.execute(request);
   

6. 响应体转字符串（辅助方法）：

   String responseString = convertResponseToString(httpResponse);
   

   辅助方法实现：

   private String convertResponseToString(HttpResponse response) throws IOException {
       InputStream responseStream = response.getEntity().getContent();
       Scanner scanner = new Scanner(responseStream, "UTF-8");
       String responseString = scanner.useDelimiter("\\Z").next();
       scanner.close();
       return responseString;
   }
   

7. 验证行为：

   verify(getRequestedFor(urlEqualTo("/baeldung"))); // 验证请求URL
   assertEquals("Welcome to Baeldung!", responseString); // 验证响应体
   

8. 释放资源：

   wireMockServer.stop();
   

4. JUnit 管理服务器

本节展示如何使用 JUnit Rule 自动管理 WireMock 服务器生命周期。

4.1. 服务器设置

通过 @Rule 注解集成 JUnit：

• JUnit 自动在测试方法前启动服务器，方法后停止服务器
• 可指定端口（未指定时默认 8080）

@Rule
public WireMockRule wireMockRule = new WireMockRule(int port);

提示：可通过 Options 接口配置主机（默认 localhost）等参数。

4.2. URL 匹配

使用正则表达式匹配接口路径：

1. 配置存根：

   stubFor(get(urlPathMatching("/baeldung/.*"))
       .willReturn(aResponse()
           .withStatus(200)
           .withHeader("Content-Type", "application/json")
           .withBody("\"testing-library\": \"WireMock\"")));
   

2. 执行请求：

   CloseableHttpClient httpClient = HttpClients.createDefault();
   HttpGet request = new HttpGet("http://localhost:8080/baeldung/wiremock");
   HttpResponse httpResponse = httpClient.execute(request);
   String stringResponse = convertHttpResponseToString(httpResponse);
   

   辅助方法：

   private String convertHttpResponseToString(HttpResponse httpResponse) throws IOException {
       InputStream inputStream = httpResponse.getEntity().getContent();
       return convertInputStreamToString(inputStream);
   }
   
   private String convertInputStreamToString(InputStream inputStream) {
       Scanner scanner = new Scanner(inputStream, "UTF-8");
       String string = scanner.useDelimiter("\\Z").next();
       scanner.close();
       return string;
   }
   

3. 验证结果：

   verify(getRequestedFor(urlEqualTo("/baeldung/wiremock")));
   assertEquals(200, httpResponse.getStatusLine().getStatusCode());
   assertEquals("application/json", httpResponse.getFirstHeader("Content-Type").getValue());
   assertEquals("\"testing-library\": \"WireMock\"", stringResponse);
   

4.3. 请求头匹配

演示基于请求头的存根配置：

1. 配置存根（匹配 Accept 头）：

   stubFor(get(urlPathEqualTo("/baeldung/wiremock"))
       .withHeader("Accept", matching("text/.*"))
       .willReturn(aResponse()
           .withStatus(503)
           .withHeader("Content-Type", "text/html")
           .withBody("!!! Service Unavailable !!!")));
   

2. 执行请求（添加请求头）：

   CloseableHttpClient httpClient = HttpClients.createDefault();
   HttpGet request = new HttpGet("http://localhost:8080/baeldung/wiremock");
   request.addHeader("Accept", "text/html");
   HttpResponse httpResponse = httpClient.execute(request);
   String stringResponse = convertHttpResponseToString(httpResponse);
   

3. 验证结果：

   verify(getRequestedFor(urlEqualTo("/baeldung/wiremock")));
   assertEquals(503, httpResponse.getStatusLine().getStatusCode());
   assertEquals("text/html", httpResponse.getFirstHeader("Content-Type").getValue());
   assertEquals("!!! Service Unavailable !!!", stringResponse);
   

4.4. 请求体匹配

演示基于请求体的存根配置：

1. 配置存根（匹配 JSON 请求体）：

   stubFor(post(urlEqualTo("/baeldung/wiremock"))
       .withHeader("Content-Type", equalTo("application/json"))
       .withRequestBody(containing("\"testing-library\": \"WireMock\""))
       .withRequestBody(containing("\"creator\": \"Tom Akehurst\""))
       .withRequestBody(containing("\"website\": \"wiremock.org\""))
       .willReturn(aResponse()
           .withStatus(200)));
   

2. 准备请求体（从 classpath 加载 JSON）：

   InputStream jsonInputStream = 
       this.getClass().getClassLoader().getResourceAsStream("wiremock_intro.json");
   String jsonString = convertInputStreamToString(jsonInputStream);
   StringEntity entity = new StringEntity(jsonString);
   

   wiremock_intro.json 内容：

   {
       "testing-library": "WireMock",
       "creator": "Tom Akehurst",
       "website": "wiremock.org"
   }
   

3. 执行请求：

   CloseableHttpClient httpClient = HttpClients.createDefault();
   HttpPost request = new HttpPost("http://localhost:8080/baeldung/wiremock");
   request.addHeader("Content-Type", "application/json");
   request.setEntity(entity);
   HttpResponse response = httpClient.execute(request);
   

4. 验证结果：

   verify(postRequestedFor(urlEqualTo("/baeldung/wiremock"))
       .withHeader("Content-Type", equalTo("application/json")));
   assertEquals(200, response.getStatusLine().getStatusCode());
   

4.5. 存根优先级

处理多个存根匹配同一请求的场景：

踩坑提示：默认情况下，最近添加的存根优先级最高。可通过 atPriority() 覆盖此行为（数值越小优先级越高）。

场景一：未设置优先级

1. 配置两个存根：

   stubFor(get(urlPathMatching("/baeldung/.*"))
       .willReturn(aResponse().withStatus(200)));
   
   stubFor(get(urlPathEqualTo("/baeldung/wiremock"))
       .withHeader("Accept", matching("text/.*"))
       .willReturn(aResponse().withStatus(503)));
   

2. 执行请求（使用辅助方法）：

   HttpResponse httpResponse = generateClientAndReceiveResponseForPriorityTests();
   

   辅助方法：

   private HttpResponse generateClientAndReceiveResponseForPriorityTests() throws IOException {
       CloseableHttpClient httpClient = HttpClients.createDefault();
       HttpGet request = new HttpGet("http://localhost:8080/baeldung/wiremock");
       request.addHeader("Accept", "text/xml");
       return httpClient.execute(request);
   }
   

3. 验证结果（后配置的存根生效）：

   verify(getRequestedFor(urlEqualTo("/baeldung/wiremock")));
   assertEquals(503, httpResponse.getStatusLine().getStatusCode());
   

场景二：设置优先级

1. 配置带优先级的存根：

   stubFor(get(urlPathMatching("/baeldung/.*"))
       .atPriority(1) // 高优先级
       .willReturn(aResponse().withStatus(200)));
   
   stubFor(get(urlPathEqualTo("/baeldung/wiremock"))
       .atPriority(2) // 低优先级
       .withHeader("Accept", matching("text/.*"))
       .willReturn(aResponse().withStatus(503)));
   

2. 执行请求（同场景一）：

   HttpResponse httpResponse = generateClientAndReceiveResponseForPriorityTests();
   

3. 验证结果（高优先级存根生效）：

   verify(getRequestedFor(urlEqualTo("/baeldung/wiremock")));
   assertEquals(200, httpResponse.getStatusLine().getStatusCode());
   

5. 总结

本文介绍了 WireMock 的核心功能，包括：

• 手动/JUnit 两种服务器管理方式
• URL/请求头/请求体匹配技巧
• 存根优先级控制机制

通过这些技术，可以高效构建 REST API 测试的模拟服务。完整示例代码可在 GitHub 项目 中获取。