Spring Webflux WebClient搭配Jetty HttpClient时指标丢失解决方案咨询

需求目标 #

使用Spring Webflux WebClient时，基于Jetty HttpClient（而非Netty）获取相关指标。

已尝试配置 #

Java配置 #

@Bean
@Primary
public WebClient getWebClient(final HttpClient httpClient) {
    return WebClient.builder()
            .baseUrl("http://some-host:8080/api/path")
            .defaultHeader(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
            .clientConnector(new JettyClientHttpConnector(httpClient))
            .build();
}

@Bean
public HttpClient getHttpClient(final MeterRegistry registry) {
    final var sslContextFactory = new SslContextFactory.Client();
    sslContextFactory.setSslContext(getCustomSSLContext());
    final var clientConnector = new ClientConnector();
    clientConnector.setSslContextFactory(sslContextFactory);
    final var httpClient = new HttpClient(new HttpClientTransportDynamic(clientConnector));
    return httpClient;
}

Maven依赖 #

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-webflux</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
    <groupId>io.micrometer</groupId>
    <artifactId>micrometer-registry-elastic</artifactId>
</dependency>
<dependency>
    <groupId>io.micrometer</groupId>
    <artifactId>micrometer-tracing-bridge-otel</artifactId>
</dependency>
<dependency>
    <groupId>io.opentelemetry</groupId>
    <artifactId>opentelemetry-exporter-otlp</artifactId>
</dependency>
<dependency>
    <groupId>org.eclipse.jetty</groupId>
    <artifactId>jetty-reactive-httpclient</artifactId>
</dependency>

当前问题 #

未获取到任何Webflux WebClient相关指标，也无Jetty相关指标。改用Netty作为客户端连接器时，可正常采集到reactor_netty相关指标。

解决方案 #

1. 添加Jetty Micrometer支持依赖 #

Jetty HttpClient的指标采集需要额外的jetty-micrometer模块，在Maven依赖中添加：

<dependency>
    <groupId>org.eclipse.jetty</groupId>
    <artifactId>jetty-micrometer</artifactId>
</dependency>

2. 配置Jetty HttpClient绑定指标注册表 #

修改getHttpClient方法，将MeterRegistry绑定到Jetty客户端，启用指标采集：

@Bean
public HttpClient getHttpClient(final MeterRegistry registry) {
    final var sslContextFactory = new SslContextFactory.Client();
    sslContextFactory.setSslContext(getCustomSSLContext());
    final var clientConnector = new ClientConnector();
    clientConnector.setSslContextFactory(sslContextFactory);
    
    final var httpClient = new HttpClient(new HttpClientTransportDynamic(clientConnector));
    // 绑定MeterRegistry到Jetty客户端，启用指标
    httpClient.addBean(new MeterRegistryListener(registry));
    httpClient.setMetricRegistry(registry);
    
    return httpClient;
}

3. 启用WebClient的观测支持 #

Spring Webflux的WebClient指标依赖观测框架，需要在构建WebClient时注入ObservationRegistry：

@Bean
@Primary
public WebClient getWebClient(final HttpClient httpClient, final ObservationRegistry observationRegistry) {
    return WebClient.builder()
            .baseUrl("http://some-host:8080/api/path")
            .defaultHeader(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
            .clientConnector(new JettyClientHttpConnector(httpClient))
            // 启用观测，生成WebClient专属指标
            .observationRegistry(observationRegistry)
            .build();
}

4. 确认Actuator端点配置 #

在配置文件（如application.yml）中确保启用指标端点暴露：

management:
  endpoints:
    web:
      exposure:
        include: metrics,health
  metrics:
    tags:
      application: your-app-name # 可选：添加全局应用标签，方便指标区分

验证指标 #

启动应用后，访问/actuator/metrics端点，可查看以下核心指标：

• jetty.client.requests.active：当前活跃的Jetty客户端请求数
• jetty.client.requests.total：Jetty客户端处理的总请求数
• webclient.requests：WebClient请求指标，包含状态码、目标URI等标签维度

内容的提问来源于stack exchange，提问作者PatPanda