SpringCloud2020学习笔记14——SpringCloud Sleuth分布式请求链路追踪

一、概述

1、为什么会出现这个技术？需要解决哪些问题？

2、简介

https://github.com/spring-cloud/spring-cloud-sleuth
Spring Cloud Sleuth提供了一套完整的服务跟踪的解决方案
在分布式系统中提供追踪解决方案并且兼容支持了zipkin

二、搭建链路监控步骤

1、zipkin

① 下载

SpringCloud从F版起已不需要自己构建Zipkin server了，只需要调用jar包即可
https://dl.bintray.com/openzipkin/maven/io/zipkin/java/zipkin-server/
zipkin-server-2.12.9.exec.jar

② 运行jar

③ 运行控制台

http://localhost:9411/zipkin/

④ 术语

• Trace:类似于树结构的Span集合，表示一条调用链路，存在唯一标识
• span:表示调用链路来源，通俗的理解span就是一次请求信息

2、服务提供者

① cloud-provider-payment8001

② POM

<!--包含了sleuth+zipkin-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-zipkin</artifactId>
        </dependency>

③ YML

server:
  port: 8001

spring:
  application:
    name: cloud-payment-service
  zipkin:
    base-url: http://localhost:9411
    sleuth:
      sampler:
      probability: 1
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource    #当前数据源操作类型
    driver-class-name: org.gjt.mm.mysql.Driver        #mysql驱动包
    url: jdbc:mysql://localhost:3306/db2020?useUnicode=true&characterEncoding=utf-8&useSSL=false
    username: root
    password: 123456

mybatis:
  mapper-locations: classpath:mapper/*.xml
  type-aliases-package: com.radish.springcloud.entities     #所有Entity别名类所在包

eureka:
  client:
    register-with-eureka: true
    fetchRegistry: true
    service-url:
#      defaultZone: http://localhost:7001/eureka
      defaultZone: http://eureka7001.com:7001/eureka,http://eureka7002.com:7002/eureka  #集群版
  instance:
    instance-id: payment8001
    prefer-ip-address: true

④ 业务类PaymentController

@GetMapping("/payment/zipkin")
    public String paymentZipkin() {
        return "hi ,i'am paymentzipkin server fall back，welcome to atguigu，O(∩_∩)O哈哈~";
    }

3、服务消费者（调用方）

① cloud-consumer-order80

② POM

		<dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-zipkin</artifactId>
        </dependency>

③ YML

server:
  port: 80

spring:
  application:
    name: cloud-order-service
  zipkin:
    base-url: http://localhost:9411
    sleuth:
      sampler:
        #采样率介于0到1之间，1表示全部采集
      probability: 1


eureka:
  client:
    #表示会否将自己注册金EurekaServer默认为true
    register-with-eureka: true
    #是否从EurekaServer抓取已有的注册信息，默认为true。单节点无所谓，集群必须设置为true才能配合ribbon使用负载均衡
    fetchRegistry: true
    service-url:
#      defaultZone: http://localhost:7001/eureka
      defaultZone: http://eureka7001.com:7001/eureka,http://eureka7002.com:7002/eureka  #集群版

④ Controller

 // ====================> zipkin+sleuth
    @GetMapping("/consumer/payment/zipkin")
    public String paymentZipkin()
    {
        String result = restTemplate.getForObject("http://localhost:8001"+"/payment/zipkin/", String.class);
        return result;
    }
 

4、依次启动eureka7001/8001/80

80调用8001几次测试下

5、打开浏览器访问:http:localhost:9411

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