Spring Cloud Sleuth链路跟踪之使用Mysq保存服务链路跟踪信息(学习总结)

一、简介

我们在上上一篇文章(https://blog.csdn.net/Weixiaohuai/article/details/82883280)已经实现了通过RabbitMQ消息中间件的方式来收集服务链路跟踪信息，但是当zipkin-server服务端重启之后，你会发现之前的链路信息都清空了，通过zipkin可视化界面已经不能看到服务之间的调用关系以及服务依赖关系了，这个时候我们就需要考虑将服务链路信息进行持久化，通常都是保存在数据库或者搜索引擎如ES中，本文将实现将服务链路跟踪信息保存在Mysql数据库中，从而实现链路信息的持久化。

二、修改zipkin-server

本章内容需要依据上上一篇文章(https://blog.csdn.net/Weixiaohuai/article/details/82883280)的项目工程，没看的可以先看上上一篇文章。将链路信息保存数据库，主要改动是在zipkin-server服务端。

【a】在zipkin-server的pom.xml中添加依赖

 <!--mysql数据库配置-->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.25</version>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>

【b】application.yml中添加数据库配置、zipkin保存方式等信息，具体配置文件如下

server:
  port: 2222
spring:
  application:
    name: zipkin-server
#RabbitMQ配置
  rabbitmq:
    port: 5672
    username: guest
    password: guest
    host: localhost
#数据库配置
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/sleuth_zipkin_mysql?useUnicode=true&characterEncoding=utf8&useSSL=false
    username: root
    password: wsh0905
#当前程序不使用sleuth
  sleuth:
    enabled: false
#表示zipkin数据存储方式是mysql
zipkin:
  storage:
    type: mysql
#服务注册中心地址配置
eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:1111/eureka/

【c】在数据库中创建存储链路信息的相关表，主要有:

zipkin_spans、zipkin_annotations、zipkin_dependencies三张表，具体sql:

CREATE TABLE IF NOT EXISTS zipkin_spans (
  `trace_id_high` BIGINT NOT NULL DEFAULT 0 COMMENT 'If non zero, this means the trace uses 128 bit traceIds instead of 64 bit',
  `trace_id` BIGINT NOT NULL,
  `id` BIGINT NOT NULL,
  `name` VARCHAR(255) NOT NULL,
  `parent_id` BIGINT,
  `debug` BIT(1),
  `start_ts` BIGINT COMMENT 'Span.timestamp(): epoch micros used for endTs query and to implement TTL',
  `duration` BIGINT COMMENT 'Span.duration(): micros used for minDuration and maxDuration query'
) ENGINE=InnoDB ROW_FORMAT=COMPRESSED CHARACTER SET=utf8 COLLATE utf8_general_ci;

ALTER TABLE zipkin_spans ADD UNIQUE KEY(`trace_id_high`, `trace_id`, `id`) COMMENT 'ignore insert on duplicate';
ALTER TABLE zipkin_spans ADD INDEX(`trace_id_high`, `trace_id`, `id`) COMMENT 'for joining with zipkin_annotations';
ALTER TABLE zipkin_spans ADD INDEX(`trace_id_high`, `trace_id`) COMMENT 'for getTracesByIds';
ALTER TABLE zipkin_spans ADD INDEX(`name`) COMMENT 'for getTraces and getSpanNames';
ALTER TABLE zipkin_spans ADD INDEX(`start_ts`) COMMENT 'for getTraces ordering and range';

CREATE TABLE IF NOT EXISTS zipkin_annotations (
  `trace_id_high` BIGINT NOT NULL DEFAULT 0 COMMENT 'If non zero, this means the trace uses 128 bit traceIds instead of 64 bit',
  `trace_id` BIGINT NOT NULL COMMENT 'coincides with zipkin_spans.trace_id',
  `span_id` BIGINT NOT NULL COMMENT 'coincides with zipkin_spans.id',
  `a_key` VARCHAR(255) NOT NULL COMMENT 'BinaryAnnotation.key or Annotation.value if type == -1',
  `a_value` BLOB COMMENT 'BinaryAnnotation.value(), which must be smaller than 64KB',
  `a_type` INT NOT NULL COMMENT 'BinaryAnnotation.type() or -1 if Annotation',
  `a_timestamp` BIGINT COMMENT 'Used to implement TTL; Annotation.timestamp or zipkin_spans.timestamp',
  `endpoint_ipv4` INT COMMENT 'Null when Binary/Annotation.endpoint is null',
  `endpoint_ipv6` BINARY(16) COMMENT 'Null when Binary/Annotation.endpoint is null, or no IPv6 address',
  `endpoint_port` SMALLINT COMMENT 'Null when Binary/Annotation.endpoint is null',
  `endpoint_service_name` VARCHAR(255) COMMENT 'Null when Binary/Annotation.endpoint is null'
) ENGINE=InnoDB ROW_FORMAT=COMPRESSED CHARACTER SET=utf8 COLLATE utf8_general_ci;

ALTER TABLE zipkin_annotations ADD UNIQUE KEY(`trace_id_high`, `trace_id`, `span_id`, `a_key`, `a_timestamp`) COMMENT 'Ignore insert on duplicate';
ALTER TABLE zipkin_annotations ADD INDEX(`trace_id_high`, `trace_id`, `span_id`) COMMENT 'for joining with zipkin_spans';
ALTER TABLE zipkin_annotations ADD INDEX(`trace_id_high`, `trace_id`) COMMENT 'for getTraces/ByIds';
ALTER TABLE zipkin_annotations ADD INDEX(`endpoint_service_name`) COMMENT 'for getTraces and getServiceNames';
ALTER TABLE zipkin_annotations ADD INDEX(`a_type`) COMMENT 'for getTraces';
ALTER TABLE zipkin_annotations ADD INDEX(`a_key`) COMMENT 'for getTraces';
ALTER TABLE zipkin_annotations ADD INDEX(`trace_id`, `span_id`, `a_key`) COMMENT 'for dependencies job';

CREATE TABLE IF NOT EXISTS zipkin_dependencies (
  `day` DATE NOT NULL,
  `parent` VARCHAR(255) NOT NULL,
  `child` VARCHAR(255) NOT NULL,
  `call_count` BIGINT,
  `error_count` BIGINT
) ENGINE=InnoDB ROW_FORMAT=COMPRESSED CHARACTER SET=utf8 COLLATE utf8_general_ci;

ALTER TABLE zipkin_dependencies ADD UNIQUE KEY(`day`, `parent`, `child`);

通过改动zipkin server，这样就可以实现mysql存储链路信息。

三、启动项目

依次启动eureka-server、api-gateway、user-service、zipkin-server,我们先访问http://localhost:3333/user/sayHello/weishihuai，

Spring Cloud Sleuth链路跟踪之使用Mysq保存服务链路跟踪信息(学习总结)-LMLPHP

可以看到，接口调用成功，这时候我们再访问zipkin server可视化界面http://localhost:2222/zipkin/dependency/，

Spring Cloud Sleuth链路跟踪之使用Mysq保存服务链路跟踪信息(学习总结)-LMLPHP

如图，可以看到rabbitMQ成功收集了服务链路信息。这时候我们查询数据库中相关表的数据，

Spring Cloud Sleuth链路跟踪之使用Mysq保存服务链路跟踪信息(学习总结)-LMLPHP

由图，我们已经实现了将链路信息持久化到数据库中。

四、总结

上面我们通过改造zipkin-server将服务链路跟踪信息保存到数据库中，当然，在实际项目中，也可以保存在搜索引擎(如ES中),

这需要根据具体项目规模以及项目需求来定，以上是作者在学习Spring Cloud Sleuth持久化链路信息的一些总结以及方法，仅供大家参考，一起学习一起进步!

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