目前很多业务使用微服务架构，服务模块划分有这2种方式：
服务功能划分 业务划分
不管哪种方式，一次接口调用都需要多个服务协同完成，其中一个服务出现问题，都会导致最终失败，虽然有logback + kafka + ELK 这样的神器架构，但是定位问题也很麻烦，如果在整个链路中，可以通过一个唯一ID（traceId）跟踪本次服务调用，就可以在ELK中查找当前traceId来定位问题。
一、案例1、案例结构
pratices-demo-provider-core：定义服务接口 pratices-demo-provider：具体实现 pratices-demo-consumer-core：服务消费者，同时也是服务提供者 pratices-demo-consumer：具体实现 pratices-demo-web：提供http服务 pratices-demo-trace：本案例的核心模块，在服务调用时拦截，设置traceId，跟踪本次服务调用2、pratices-demo
2.1、pom.xml
<?xml version="1.0" encoding="UTF-8"?><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <packaging>pom</packaging> <modules> <module>pratices-demo-consumer</module> <module>pratices-demo-provider</module> <module>pratices-demo-provider-core</module> <module>pratices-demo-consumer-core</module> <module>pratices-demo-web</module> <module>pratices-demo-trace</module> </modules> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.4.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.cn.dl</groupId> <artifactId>pratices-demo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>pratices-demo</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-autoconfigure</artifactId> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>dubbo</artifactId> <version>2.6.0</version> <exclusions> <exclusion> <groupId>org.springframework</groupId> <artifactId>spring</artifactId> </exclusion> <exclusion> <groupId>ch.qos.logback</groupId> <artifactId>logback-core</artifactId> </exclusion> <exclusion> <groupId>ch.qos.logback</groupId> <artifactId>logback-access</artifactId> </exclusion> <exclusion> <groupId>ch.qos.logback</groupId> <artifactId>logback-classic</artifactId> </exclusion> <exclusion> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.apache.zookeeper</groupId> <artifactId>zookeeper</artifactId> <version>3.4.10</version> </dependency> <!--Exception in thread "main" java.lang.NoClassDefFoundError: org/I0Itec/zkclient/IZkStateListener--> <!--Caused by: java.lang.ClassNotFoundException: org.I0Itec.zkclient.IZkStateListener--> <dependency> <groupId>com.101tec</groupId> <artifactId>zkclient</artifactId> <version>0.10</version> <exclusions> <exclusion> <artifactId>slf4j-log4j12</artifactId> <groupId>org.slf4j</groupId> </exclusion> </exclusions> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> </repository> <repository> <id>spring-snapshots</id> <name>Spring Snapshots</name> <url>https://repo.spring.io/snapshot</url> <snapshots> <enabled>true</enabled> </snapshots> </repository> </repositories> <pluginRepositories> <pluginRepository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> </pluginRepository> <pluginRepository> <id>spring-snapshots</id> <name>Spring Snapshots</name> <url>https://repo.spring.io/snapshot</url> <snapshots> <enabled>true</enabled> </snapshots> </pluginRepository> </pluginRepositories> </project>
3、pratices-demo-provider-core
3.1、ProviderService
package com.cn.dl; /** * Created by yanshao on 2019-09-04. */public interface ProviderService { String sayHello(String name);}
4、pratices-demo-provider
4.1、ProviderServiceImpl
package com.cn.dl.provider.impl; import com.alibaba.dubbo.config.annotation.Service;import com.cn.dl.ProviderService;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.slf4j.MDC; /** * Created by yanshao on 2019-09-04. */@Servicepublic class ProviderServiceImpl implements ProviderService { private static final Logger log = LoggerFactory.getLogger(ProviderServiceImpl.class); @Override public String sayHello(String name) { log.info("providerServiceImpl 服务提供 traceId:{},sayHello:{}", MDC.get("traceId"),name); return "hello " + name ; }}
4.2、dubbo-provider.properties 配置文件
# dubbo-provider.propertiesdubbo.application.name=service2dubbo.registry.address=zookeeper://127.0.0.1:2181dubbo.protocol.name=dubbodubbo.protocol.port=50010dubbo.consumer.timeout=5000
4.3、ProviderMain服务启动类
注意：启动dubbo服务不需要暴露http服务
package com.cn.dl; import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.boot.WebApplicationType;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.boot.builder.SpringApplicationBuilder;import org.springframework.context.annotation.PropertySource; import java.util.concurrent.locks.LockSupport; /** * Created by yanshao on 2019-09-04. */@EnableDubbo(scanBasePackages = "com.cn.dl*")@PropertySource("classpath:/dubbo-provider.properties")@SpringBootApplicationpublic class ProviderMain{ private static final Logger log = LoggerFactory.getLogger(ProviderMain.class); /** * 启动dubbo服务，不需要提供web服务，但是默认有8080端口，通过一下方式可以不暴露web服务 * * 1、在application.properties加上一下配置 * * spring: * main: * allow-bean-definition-overriding: true * web-application-type: none * * 2、修改启动类 * new SpringApplicationBuilder(ProviderMain .class) * .web(WebApplicationType.NONE) * .run(args) * */ public static void main(String[] args) { new SpringApplicationBuilder(ProviderMain.class).web(WebApplicationType.NONE).run(args); log.info("ProviderMain 启动了"); LockSupport.park(); }}
@EnableDubbo(scanBasePackages = "com.cn.dl*")
扫描Dubbo的服务提供者以及Dubbo的服务消费者，一定要注意@EnableDubbo和@SpringBootApplication的先后次序；
@PropertySource("classpath:/dubbo-provider.properties")
加载配置文件到上下文环境变量。
5、pratices-demo-consumer-core
5.1、ConsumerService
package com.cn.dl; /** * Created by yanshao on 2019-09-04. */public interface ConsumerService { String toSayHello(String name); int getRandomInt();}
6、pratices-demo-consumer
6.1、ConsumerServiceImpl
package com.cn.dl.consumer.impl; import com.alibaba.dubbo.config.annotation.Reference;import com.alibaba.dubbo.config.annotation.Service;import com.cn.dl.ConsumerService;import com.cn.dl.ProviderService;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.slf4j.MDC; import java.util.Random; /** * Created by yanshao on 2019-09-04. */@Servicepublic class ConsumerServiceImpl implements ConsumerService { private static final Logger log = LoggerFactory.getLogger(ConsumerServiceImpl.class); @Reference private ProviderService providerService; @Override public String toSayHello(String name) { String sayHello = providerService.sayHello(name); log.info("ConsumerServiceImpl >>>> traceId:{},sayHello:{}", MDC.get("traceId"),sayHello); return sayHello; } @Override public int getRandomInt() { return new Random().nextInt(100); }}
6.2、dubbo-consumer.properties
dubbo.application.name=service1dubbo.registry.address=zookeeper://127.0.0.1:2181dubbo.protocol.name=dubbodubbo.protocol.port=50020dubbo.consumer.timeout=5000
6.3、ConsumerMain
package com.cn.dl; import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;import org.springframework.boot.WebApplicationType;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.boot.builder.SpringApplicationBuilder;import org.springframework.context.annotation.PropertySource; import java.util.concurrent.locks.LockSupport; /** * Created by yanshao on 2019-09-04. */@EnableDubbo(scanBasePackages = "com.cn.dl*")@PropertySource("classpath:/dubbo-consumer.properties")@SpringBootApplicationpublic class ConsumerMain { public static void main(String[] args) { new SpringApplicationBuilder(ConsumerMain.class).web(WebApplicationType.NONE).run(args); LockSupport.park(); }}
7、pratices-demo-web
7.1、WebTraceFilter
定义web拦截器，拦截所有请求，生成唯一ID
package com.cn.dl.webTrace; import com.cn.dl.utils.TraceUtil;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.slf4j.MDC; import javax.servlet.*;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException; import static com.cn.dl.config.TraceConfig.TRACE_ID; /** * Created by yanshao on 2019-09-04. */public class WebTraceFilter implements Filter { private static final Logger log = LoggerFactory.getLogger(WebTraceFilter.class); @Override public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException { if (! (servletRequest instanceof HttpServletRequest) || ! (servletResponse instanceof HttpServletResponse)) { throw new ServletException("只支持http请求"); } try { String traceId = TraceUtil.getTraceId(); log.info("WebTraceFilter traceId:{}",traceId); MDC.put(TRACE_ID,traceId); filterChain.doFilter(servletRequest, servletResponse); } finally { MDC.remove(TRACE_ID); } }}
7.2、TraceUtil
package com.cn.dl.utils; import java.util.UUID; /** * Created by yanshao on 2019-09-04. */public class TraceUtil { public static String getTraceId(){ return UUID.randomUUID().toString().replace("-",""); } public static void main(String[] args) { System.out.println(getTraceId()); }}
7.3、TraceConfig
package com.cn.dl.config; /** * Created by yanshao on 2019-09-04. */public interface TraceConfig { String TRACE_ID = "traceId";}
7.4、RpcProviderInterceptor
package com.cn.dl.rpcTrace; import com.alibaba.dubbo.common.Constants;import com.alibaba.dubbo.common.extension.Activate;import com.alibaba.dubbo.rpc.*;import com.cn.dl.utils.TraceUtil;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.slf4j.MDC;import org.springframework.util.StringUtils; import java.util.Map; import static com.cn.dl.config.TraceConfig.TRACE_ID;/** * Created by yanshao on 2019-09-04. */@Activate(group = Constants.PROVIDER)public class RpcProviderInterceptor implements Filter { private static final Logger log = LoggerFactory.getLogger(RpcProviderInterceptor.class); @Override public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException { Result result; try { Map<String, String> at = invocation.getAttachments(); MDC.put(TRACE_ID, ! StringUtils.isEmpty(at.get(TRACE_ID)) ? at.get(TRACE_ID): TraceUtil.getTraceId()); result = invoker.invoke(invocation); } catch (Exception e) { log.error("RpcProviderInterceptor 异常",e); throw e; } finally { MDC.remove(TRACE_ID); } return result; }}
7.5、RpcConsumerInterceptor
package com.cn.dl.rpcTrace; import com.alibaba.dubbo.common.Constants;import com.alibaba.dubbo.common.extension.Activate;import com.alibaba.dubbo.rpc.*;import com.cn.dl.utils.TraceUtil;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.slf4j.MDC; import java.util.Map; import static com.cn.dl.config.TraceConfig.TRACE_ID;/** * Created by yanshao on 2019-09-04. */@Activate(group = Constants.CONSUMER)public class RpcConsumerInterceptor implements Filter { private static final Logger log = LoggerFactory.getLogger(RpcProviderInterceptor.class); @Override public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException { Result result; try { Map<String, String> at = invocation.getAttachments(); if (MDC.get(TRACE_ID) == null) { MDC.put(TRACE_ID,TraceUtil.getTraceId()); } at.put(TRACE_ID, MDC.get(TRACE_ID)); result = invoker.invoke(invocation); }catch (Exception e){ log.error("RpcConsumerInterceptor 异常",e); throw e; } return result; }}
7.6、RpcProviderInterceptor
package com.cn.dl.rpcTrace; import com.alibaba.dubbo.common.Constants;import com.alibaba.dubbo.common.extension.Activate;import com.alibaba.dubbo.rpc.*;import com.cn.dl.utils.TraceUtil;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.slf4j.MDC;import org.springframework.util.StringUtils; import java.util.Map; import static com.cn.dl.config.TraceConfig.TRACE_ID;/** * Created by yanshao on 2019-09-04. */@Activate(group = Constants.PROVIDER)public class RpcProviderInterceptor implements Filter { private static final Logger log = LoggerFactory.getLogger(RpcProviderInterceptor.class); @Override public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException { Result result; try { Map<String, String> at = invocation.getAttachments(); MDC.put(TRACE_ID, ! StringUtils.isEmpty(at.get(TRACE_ID)) ? at.get(TRACE_ID): TraceUtil.getTraceId()); result = invoker.invoke(invocation); } catch (Exception e) { log.error("RpcProviderInterceptor 异常",e); throw e; } finally { MDC.remove(TRACE_ID); } return result; }}
然后在resources下创建META-INF/dubbo/com.alibaba.dubbo.rpc.Filter，将扩展的拦截器添加到dubbo调用链中
consumerTraceFilter=com.cn.dl.rpcTrace.RpcConsumerInterceptorproviderTraceFilter=com.cn.dl.rpcTrace.RpcProviderInterceptor
8、pratices-demo-web
8.1、TraceInterceptor注册web拦截器
package com.cn.dl.config; import com.cn.dl.webTrace.WebTraceFilter;import org.springframework.boot.SpringBootConfiguration;import org.springframework.boot.web.servlet.FilterRegistrationBean;import org.springframework.context.annotation.Bean; import javax.annotation.Resource;import javax.servlet.Filter; /** * Created by yanshao on 2019-09-04. */@SpringBootConfigurationpublic class TraceInterceptor { @Bean(name = "webTraceFilter") public WebTraceFilter getWebTraceFilter(){ return new WebTraceFilter(); } @Bean @Resource public FilterRegistrationBean traceFilterRegistration(Filter webTraceFilter) { FilterRegistrationBean<Filter> registration = new FilterRegistrationBean<>(); registration.setFilter(webTraceFilter); registration.addUrlPatterns("/*"); registration.setName("webTraceFilter"); registration.setOrder(1); return registration; }}
8.2、dubbo.properties
dubbo.application.name=consumer-servicedubbo.registry.address=zookeeper://127.0.0.1:2181dubbo.consumer.timeout=5000
8.3、DemoWebController
package com.cn.dl.controller; import com.alibaba.dubbo.config.annotation.Reference;import com.cn.dl.ConsumerService;import org.springframework.web.bind.annotation.*; /** * Created by yanshao on 2019-09-04. */@RestControllerpublic class DemoWebController { @Reference private ConsumerService consumerService; @PostMapping("sayHello") public String sayHello(@RequestParam("name") String name){ return consumerService.toSayHello(name); } @GetMapping("getRandomInt") public int getRandomInt(){ return consumerService.getRandomInt(); } }
8.4、StartWeb
package com.cn.dl; import com.alibaba.dubbo.config.spring.context.annotation.EnableDubbo;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.context.annotation.PropertySource; /** * Created by yanshao on 2019-09-04. */@EnableDubbo(scanBasePackages = "com.cn.dl*")@PropertySource("classpath:/dubbo.properties")@SpringBootApplicationpublic class StartWeb { public static void main(String[] args) { SpringApplication.run(StartWeb.class,args); }}
9、分别启动providerMain、consumerMain、startWeb
以上为个人经验，希望能给大家一个参考，也希望大家多多支持。
勤奋，它是一块可以吸引到一切美好事物的天然磁石，它比黄金珍贵，
