SpringCloud之Ribbon

版权声明： https://blog.csdn.net/qq_24313635/article/details/84141294

Ribbon简介

Spring Cloud Ribbon 是基于 Netflix Ribbon 实现的一套客户端负载均衡工具，其主要功能是提供客户端的软件负载均衡算法，将 Netflix 的中间层服务连接在一起。

其运行原理如下图：

Ribbon 运行时分成 2 个步骤：

1) 先选择在同一个区域负载较少的 EurekaServer;

2) 再根据用户指定的策略，在从 EurekaServer 中获取注册列表中的服务信息进行调用。

其中，Ribbon 提供多种负载均衡策略：如轮询、随机、响应时间加权等。

Spring cloud有两种服务调用方式，一种是ribbon+restTemplate，另一种是feign（Feign默认集成了ribbon）。在这一篇文章首先介绍ribbon+restTemplate。

Ribbon实践

在上一篇的基础上，新建一个Ribbon的maven子项目，项目结构

①pom.xml（添加 spring-cloud-starter-eureka包时，会自动添加 Ribbon 依赖包。）

<?xml version="1.0"?>
<project
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
	xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
	<modelVersion>4.0.0</modelVersion>
	
	<parent>
		<groupId>com.yj</groupId>
		<artifactId>SpringCloud</artifactId>
		<version>0.0.1-SNAPSHOT</version>
	</parent>
	
	<artifactId>Ribbon</artifactId>
	<name>Ribbon</name>
	<url>http://maven.apache.org</url>
	
	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
	</properties>
	
	<dependencies>
		<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-eureka</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
	</dependencies>
	
	<build>
		<finalName>${artifactId}</finalName>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
				<configuration>
					<skip>true</skip>
				</configuration>
			</plugin>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-jar-plugin</artifactId>
				<configuration>

					<archive>
						<manifest>
							<mainClass>com.yj.ribbon.RibbonApplication</mainClass>
							<addClasspath>true</addClasspath>
							<classpathPrefix>lib</classpathPrefix>
						</manifest>
						<manifestEntries>
							<Class-Path>./</Class-Path>
						</manifestEntries>
					</archive>
					<excludes>
						<exclude>config/**</exclude>
						<exclude>**.xml</exclude>
						<exclude>**.properties</exclude>
					</excludes>
				</configuration>
			</plugin>
			<plugin>
				<artifactId>maven-assembly-plugin</artifactId>
				<configuration>
					<appendAssemblyId>false</appendAssemblyId>
					<descriptors>
						<descriptor>src/main/build/package.xml</descriptor>
					</descriptors>
				</configuration>
				<executions>
					<execution>
						<id>make-assembly</id>
						<phase>package</phase>
						<goals>
							<goal>single</goal>
						</goals>
					</execution>
				</executions>
			</plugin>
		</plugins>
		<testResources>
			<testResource>
				<directory>src/main/resources</directory>
			</testResource>
		</testResources>
	</build>
</project>

②RibbonController

package com.yj.ribbon.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import com.yj.ribbon.service.RibbonService;

@RestController
public class RibbonController {

	@Autowired
	private RibbonService ribbonService;

	@GetMapping(value = "/hiRibbon")
	public String hiRibbon(@RequestParam String name) {
		return ribbonService.hiRibbon(name);
	}
}

③RibbonService

package com.yj.ribbon.service;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

@Service
public class RibbonService {

	@Autowired
	private RestTemplate restTemplate;

	public String hiRibbon(String name) {
		return restTemplate.getForObject("http://EUREKA-CLIENT/hiEureka?name=" + name, String.class);
	}
}

④application.properties

server.port=8005

spring.application.name=ribbon
eureka.client.serviceUrl.defaultZone=http://admin:[email protected]:8001/eureka,http://admin:[email protected]:8002/eureka
eureka.instance.prefer-ip-address=true
eureka.instance.instance-id=${spring.cloud.client.ipAddress}:${server.port}
eureka.instance.hostname=${spring.cloud.client.ipAddress}

⑤logback.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration>

    <conversionRule conversionWord="clr" converterClass="org.springframework.boot.logging.logback.ColorConverter" />
    <conversionRule conversionWord="wex" converterClass="org.springframework.boot.logging.logback.WhitespaceThrowableProxyConverter" />
    <conversionRule conversionWord="wEx" converterClass="org.springframework.boot.logging.logback.ExtendedWhitespaceThrowableProxyConverter" />

    <!-- 彩色日志格式 -->
    <property name="CONSOLE_LOG_PATTERN"
              value="${CONSOLE_LOG_PATTERN:-%clr(%d{yyyy-MM-dd HH:mm:ss.SSS}){faint} %clr(${LOG_LEVEL_PATTERN:-%5p}) %clr(${PID:- }){magenta} %clr(---){faint} %clr([%15.15t]){faint} %clr(%-40.40logger{39}){cyan} %clr(:){faint} %m%n${LOG_EXCEPTION_CONVERSION_WORD:-%wEx}}" />

    <!-- 控制台打印日志的相关配置 -->
    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>${CONSOLE_LOG_PATTERN}<!--%d{yyyy-MM-dd HH:mm:ss.SSS} [%level] [%class:%line] - %m%n--></pattern>
            <charset>utf8</charset>
        </encoder>
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>debug</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>ACCEPT</onMismatch>
        </filter>
    </appender>

    <!-- 文件保存日志的相关配置 -->
    <appender name="file" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>logs/Ribbon.log</file>
        <encoder>
            <pattern>${CONSOLE_LOG_PATTERN}<!--%d{yyyy-MM-dd HH:mm:ss.SSS} [%level] [%class:%line] - %m%n--></pattern>
            <charset>utf8</charset>
        </encoder>
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>info</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>ACCEPT</onMismatch>
        </filter>
        <!-- 循环政策：基于时间创建日志文件 -->
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <fileNamePattern>logs/%d{yyyy-MM-dd}/Ribbon.%d{yyyy-MM-dd}.log</fileNamePattern>
            <maxHistory>30</maxHistory>
        </rollingPolicy>
    </appender>

    <logger name="com.yj.ribbon" level="DEBUG" />
    <!-- 基于dubug处理日志：具体控制台或者文件对日志级别的处理还要看所在appender配置的filter，如果没有配置filter，则使用root配置 -->
    <root level="info">
        <appender-ref ref="console" />
        <appender-ref ref="file" />
    </root>
</configuration>

⑥start.sh，stop.sh

#! /bin/bash

moduleName="Ribbon"

pidPath="./$moduleName-tpid"

rm -f $pidPath

java -jar ./$moduleName.jar &

echo $!>$pidPath

#! /bin/bash

moduleName="Ribbon"

tpid=`cat ./$moduleName-tpid | awk '{print $1}'`

tpid=`ps -aef | grep $tpid | grep -v grep | grep $moduleName |awk '{print $2}' `

if [ ${tpid} ];then
	kill -9 $tpid
fi

⑦package.xml

<?xml version="1.0" encoding="UTF-8"?>
<assembly xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3
          http://maven.apache.org/xsd/assembly-1.1.3.xsd">
    <id>package</id>
    <formats>
        <format>zip</format>
    </formats>
    <includeBaseDirectory>true</includeBaseDirectory>
    <fileSets>
        <fileSet>
            <directory>bin</directory>
            <outputDirectory>/</outputDirectory>
        </fileSet>
        <fileSet>
            <directory>src/main/resources</directory>
            <outputDirectory>/</outputDirectory>
            <excludes>
                <exclude>mapper/**</exclude>
            </excludes>
        </fileSet>
        <fileSet>
            <directory>${project.build.directory}</directory>
            <outputDirectory>/</outputDirectory>
            <includes>
                <include>${artifactId}.jar</include>
            </includes>
        </fileSet>
    </fileSets>
    <dependencySets>
        <dependencySet>
            <outputDirectory>lib</outputDirectory>
            <scope>runtime</scope>
            <excludes>
                <exclude>${groupId}:${artifactId}</exclude>
            </excludes>
        </dependencySet>
    </dependencySets>
</assembly>

⑧application.properties

server.port=8005

spring.application.name=ribbon
eureka.client.serviceUrl.defaultZone=http://admin:[email protected]:8001/eureka,http://admin:[email protected]:8002/eureka
eureka.instance.prefer-ip-address=true
eureka.instance.instance-id=${spring.cloud.client.ipAddress}:${server.port}
eureka.instance.hostname=${spring.cloud.client.ipAddress}

⑨RibbonApplication（@LoadBalanced注解让restTemplate可以很容易的通过ribbon实现客户端的负载均衡功能）

package com.yj.ribbon;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
@EnableEurekaClient
public class RibbonApplication {
	public static void main(String[] args) {
		SpringApplication.run(RibbonApplication.class, args);
	}
	
	@Bean
    @LoadBalanced
    RestTemplate restTemplate() {
        return new RestTemplate();
    }
}

⑩部署启动，Ribbon项目也被注册到Eureka上面了

访问http://192.168.37.139:8005/hiRibbon?name=yj，交替显示hi yj ,i am from port:8003，hi yj ,i am from port:8004