Spring Cloud Sleuth--服务链路追踪(二)

在链路中添加自定义数据

现在需要实现这样一个功能：在链路数据中加上请求的操作人。被案例在geteway-service服务中实现。在gateway-service工程中新建一个ZuulFilter过滤器，它的类型为post类型，order为900，开启拦截。在过滤器的拦截逻辑方法里，通过Tracer 的addTag 方法加上自定义的数据，在本案例中加上了链路的操作人。另外也可以在这个过滤器中获取当前链路的traceld信息，traceld 作为链路数据的唯一标识， 可以存储在log日志中，方便后续查找，本案例只是将traceld信息简单地打印在控制台上。代码如下:

@Component
public class LoggerFilter extends ZuulFilter {
    
    @Autowired
    Tracer tracer;
    
    @Override
    public String filterType() {
        return FilterConstants.POST_TYPE;
    }

    @Override
    public int filterOrder() {
        return 900;
    }

    @Override
    public boolean shouldFilter() {
        return true;
    }

    @Override
    public Object run() {
        tracer.addTag("operator", "forezp");
        System.out.println(tracer.getCurrentSpan().traceIdString());
        return null;
    }
}

使用RabbitMQ传输链路数据

在上述案例中，最终gateway-service收集的数据是通过Http上传给zipkin-server的。在SpringCloudSleuth中支持消息组件来传递链路数据。

首先改造sipkin-server工程，在其pom文件中将zipkin-server的依赖去掉，加上spring-cloud-sleuth-zipkin-stream和spring-cloud-starter-stream-rabbit的依赖：

	<dependencies>
        <dependency>
            <groupId>org.springframework.cloudgroupId>
            <artifactId>spring-cloud-starter-eurekaartifactId>
        dependency>




        <dependency>
            <groupId>io.zipkin.javagroupId>
            <artifactId>zipkin-autoconfigure-uiartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.cloudgroupId>
            <artifactId>spring-cloud-sleuth-zipkin-streamartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.cloudgroupId>
            <artifactId>spring-cloud-starter-stream-rabbitartifactId>
        dependency>
    dependencies>

配置中加上rabbitmq的配置：

server:
  port: 9411

spring:
  application:
    name: zipkin-server
  rabbitmq:
    host: localhost
    port: 5672
    username: guest
    password: guest

eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

启动类上加上@EnableZipkinStreamServer注解：

@SpringBootApplication
@EnableEurekaClient
// @EnableZipkinServer
@EnableZipkinStreamServer
public class ZipkinServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(ZipkinServerApplication.class, args);
    }
}

现在来改造Zipkin Client (包括gateway-service工程和user-service工程)，在它们的pom文件中将spring coud-tartrzipki依赖改为spring cloud-sleth-zipkin-strearmn和spring-cloud-tarterstream-rabbit,代码如下:

	<dependency>
            <groupId>org.springframework.cloudgroupId>
            <artifactId>spring-cloud-sleuth-zipkin-streamartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.cloudgroupId>
            <artifactId>spring-cloud-starter-stream-rabbitartifactId>
        dependency>

同时在配置文件applicayion.yml加上RabbitMQ的配置，同zipkin-server工程。这样，就将链路的上传数据从Http改为用消息代组件RabbitMQ。

在MySQL数据库中存储链路数据

在上面的例子中，Zipkin Server将数据存储在内存中，一旦程序重启， 之前的链路数据全部丢失，那么怎么将链路数据存储起来呢? Zipkin 支持将链路数据存储在MySQL、Elasticsearch和Cassandra数据库中。

使用Http传输链路数据，并存储在MySQL数据库中

只需要改造zipkin-server 工程。在zipkin-server工程的pom文件加上Zipkin Server 的依赖zipkin-server、Zipkin 的MySQL存储依赖zipkin-storage-mysql (这两个依赖的版本都为1.19.0)、 Zipkin Server 的UI界面依赖zipkin-autoconfigure-ui、MySQL的连接器依赖mysql-connector-java 和JDBC的起步依赖spring-boot- starter-jdbc。代码如下:

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloudgroupId>
            <artifactId>spring-cloud-starter-eurekaartifactId>
        dependency>
        
        <dependency>
            <groupId>io.zipkin.javagroupId>
            <artifactId>zipkin-serverartifactId>
        dependency>
        
        <dependency>
            <groupId>io.zipkin.javagroupId>
            <artifactId>zipkin-autoconfigure-uiartifactId>
        dependency>
        
        <dependency>
            <groupId>io.zipkin.javagroupId>
            <artifactId>zipkin-storage-mysqlartifactId>
            <version>1.19.0version>
        dependency>
        <dependency>
            <groupId>mysqlgroupId>
            <artifactId>mysql-connector-javaartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-jdbcartifactId>
        dependency>








    dependencies>

在zipkin-server工程的配置文件application.yml中加上数据源的配置，包括数据库的Url、用户名、密码和连接驱动，并且需要配置zipkin.storage.type为mysql,代码如下:

server:
  port: 9411

spring:
  application:
    name: zipkin-server
#  rabbitmq:
#    host: localhost
#    port: 5672
#    username: guest
#    password: guest
  datasource:
    url: jdbc:mysql://localhost:3306/zipkin?userUnicode=true&characterEncoding=utf8&useSSL=false
    username: root
    password: 123456
    driver-class-name: com.mysql.jdbc.Driver

zipkin:
  storage:
    type: mysql

eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

另外需要在MySQL数据库中初始化数据库脚本，数据库脚本地址为https://github.com/openzipkin/zipkin/blob/master/zipkin-storage/mysql-v1/src/main/resources/mysql.sql

--
-- Copyright 2015-2019 The OpenZipkin Authors
--
-- Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
-- in compliance with the License. You may obtain a copy of the License at
--
-- http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software distributed under the License
-- is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
-- or implied. See the License for the specific language governing permissions and limitations under
-- the License.
--

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,
  `remote_service_name` VARCHAR(255),
  `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',
  PRIMARY KEY (`trace_id_high`, `trace_id`, `id`)
) ENGINE=InnoDB ROW_FORMAT=COMPRESSED CHARACTER SET=utf8 COLLATE utf8_general_ci;

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(`remote_service_name`) COMMENT 'for getTraces and getRemoteServiceNames';
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 and autocomplete values';
ALTER TABLE zipkin_annotations ADD INDEX(`a_key`) COMMENT 'for getTraces and autocomplete values';
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,
  PRIMARY KEY (`day`, `parent`, `child`)
) ENGINE=InnoDB ROW_FORMAT=COMPRESSED CHARACTER SET=utf8 COLLATE utf8_general_ci;

最后需要在程序的启动类ZipkinServerApplication中注入MySQLStorage的Bean,代码如下:

@SpringBootApplication
@EnableEurekaClient
@EnableZipkinServer
// @EnableZipkinStreamServer
public class ZipkinServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(ZipkinServerApplication.class, args);
    }

    @Bean
    public MySQLStorage mySQLStorage(DataSource dataSource) {
        return MySQLStorage.builder()
                .datasource(dataSource)
                .executor(Runnable::run)
                .build();
    }
}