SpringCloud(四)——Ribbon

时间 2019-11-16

标签 springcloud ribbon 繁體版

原文原文链接

SpringCloud(四)——Ribbon

Ribbon简介

负载均衡框架，支持可插拔式的负载均衡规则
支持多种协议，如HTTP，UDP等
提供负载均衡客户端

Ribbon子模块

ribbon-core：核心，主要包含负载均衡器java
ribbon-eureka：为Eureka客户端提供负载均衡的实现类web
ribbon-httpclient：对HttpClient进行了封装，成为了一个具备负载均衡功能的REST客户端spring

负载均衡器

负载均衡器只少须要提供如下两种功能
- 维护各个服务器的信息，如经过负载均衡器来决定请求去哪一个服务器进行处理
- 根据特定的逻辑规则选择服务器，如A服务器处理70%的请求，B服务器处理剩下的30%的请求

Ribbon负载均衡器——三大子模块

Rule：规则，经过规则来决定请求访问那台服务器
Ping
ServerList：服务列表，全部服务器列表

第一个Ribbon程序

程序结构图以下apache

建立两个项目，客户端ribbon-client，服务端ribbon-servicejson

ribbon-service源代码服务器

pom.xmlapp

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.zgy.cloud</groupId>
	<artifactId>ribbon-service</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>ribbon-service</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.14.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter</artifactId>
		</dependency>

		<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>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>


</project>

RibbonServiceApplication.java负载均衡

package com.zgy.cloud.ribbonservice;

import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;

import java.util.Scanner;

@SpringBootApplication
public class RibbonServiceApplication {

	public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String port = scanner.next();
        new SpringApplicationBuilder(RibbonServiceApplication.class).properties("server.port="+port).run(args);
	}
}

Person.java框架

package com.zgy.cloud.ribbonservice;

public class Person {

    private Integer id;
    private String name;
    private String message;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }
}

MyController.javamaven

package com.zgy.cloud.ribbonservice;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;

@RestController
public class MyController {

    @GetMapping("/person")
    public Person getPerson(HttpServletRequest request){
        Person person = new Person();
        person.setId(1);
        person.setName("ZGY");
        person.setMessage(request.getRequestURL().toString());

        return person;
    }
}

启动两个服务，在控制台输入第一个服务的端口为8080，第二个服务的端口为8081，而后分别访问两个服务，图以下：

端口为8080的服务

端口为8081的服务

ribbon-client源代码

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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.zgy.cloud</groupId>
    <artifactId>ribbon-client</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>ribbon-client</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.14.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>com.netflix.ribbon</groupId>
            <artifactId>ribbon-core</artifactId>
            <version>2.2.2</version>
        </dependency>

        <dependency>
            <groupId>com.netflix.ribbon</groupId>
            <artifactId>ribbon-httpclient</artifactId>
            <version>2.2.2</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>commons-configuration</groupId>
            <artifactId>commons-configuration</artifactId>
            <version>1.10</version>
        </dependency>

        <dependency>
            <groupId>com.netflix.ribbon</groupId>
            <artifactId>ribbon-loadbalancer</artifactId>
            <version>2.2.2</version>
        </dependency>
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>18.0</version>
        </dependency>
        <dependency>
            <groupId>com.netflix.archaius</groupId>
            <artifactId>archaius-core</artifactId>
            <version>0.7.4</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

RibbonClientApplication.java

package com.zgy.cloud.ribbonclient;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class RibbonClientApplication {

	public static void main(String[] args) {
		SpringApplication.run(RibbonClientApplication.class, args);
	}
}

TestRibbon.java

package com.zgy.cloud.ribbonclient;

import com.netflix.client.ClientFactory;
import com.netflix.client.http.HttpRequest;
import com.netflix.client.http.HttpResponse;
import com.netflix.config.ConfigurationManager;
import com.netflix.niws.client.http.RestClient;
import java.net.URI;

public class TestRibbon {

    public static void main(String[] args) throws Exception{

        ConfigurationManager.getConfigInstance().setProperty(
                "sample-client.ribbon.listOfServers", "localhost:8080,localhost:8081");
        RestClient client = (RestClient) ClientFactory.getNamedClient("sample-client");
        HttpRequest request = HttpRequest.newBuilder().uri(new URI("/person")).build();
        for (int i = 0; i < 10; i++)  {
            HttpResponse response = client.executeWithLoadBalancer(request);
            String json = response.getEntity(String.class);
            System.out.println(json);
        }
    }
}

运行TestRibbon.java的mian方法，获得以下图结果

在控制台，咱们输出的信息，message属性的端口号是轮询的，8080和8081之间切换的

ribbon配置

前面TestRibbon.java代码中，咱们是把配置写在代码中的，代码以下

ConfigurationManager.getConfigInstance().setProperty(
                "sample-client.ribbon.listOfServers", "localhost:8080,localhost:8081");

其实咱们能够将这段配置写在一个xxx.properties文件中，配置格式为

客户端名称.命名空间.属性 = 值

如

sample-client.ribbon.listOfServers = localhost:8080,localhost:8081

ribbon读取properties文件自行解决