在SpringCloud中Ribbon負載均衡客戶端,會從eureka註冊中心服務器端上獲取服務註冊信息列表,緩存到本地。html
讓後在本地實現輪訓負載均衡策略。java
nginx是客戶端全部請求統一交給nginx,由nginx進行實現負載均衡請求轉發,屬於服務器端負載均衡。nginx
既請求有nginx服務器端進行轉發。web
Ribbon是從eureka註冊中心服務器端上獲取服務註冊信息列表,緩存到本地,讓後在本地實現輪訓負載均衡策略。spring
既在客戶端實現負載均衡。apache
Nginx適合於服務器端實現負載均衡 好比Tomcat ,Ribbon適合與在微服務中RPC遠程調用實現本地服務負載均衡,好比Dubbo、SpringCloud中都是採用本地負載均衡。api
Ribbon是Spring Cloud (本地)客戶端負載均衡器緩存
Ribbon底層實現:服務器
Member:app
pom:
<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.toov5</groupId> <artifactId>member</artifactId> <version>0.0.1-SNAPSHOT</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.1.RELEASE</version> </parent> <!-- 管理依賴 --> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Finchley.M7</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <dependencies> <!-- SpringBoot整合Web組件 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!-- SpringBoot整合eureka客戶端 --> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency> </dependencies> <!-- 注意: 這裏必需要添加, 否者各類依賴有問題 --> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/libs-milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> </project>
yml:
###服務啓動端口號 server: port: 8009 ###服務名稱(服務註冊到eureka名稱) spring: application: name: app-toov5-member ###服務註冊到eureka地址 eureka: client: service-url: ##當前會員註冊到eureka服務 地址+端口號 defaultZone: http://127.0.0.1:8100/eureka ###由於該應用爲註冊中心,不會註冊本身 register-with-eureka: true ###是否須要從eureka上獲取註冊信息 fetch-registry: true
Controller類
package com.toov5.api.controller; import org.springframework.beans.factory.annotation.Value; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; @RestController public class MemberApiController { @Value("${server.port}") private String serverPort; @RequestMapping("/getMember") public String getMember() { return "會員服務"+serverPort; } }
啓動類:
package com.toov5.api; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.netflix.eureka.EnableEurekaClient; @SpringBootApplication @EnableEurekaClient //註冊到eureka public class AppMember { public static void main(String[] args) { SpringApplication.run(AppMember.class, args); } }
Order
Controlller
package com.toov5.api.controller; import java.util.List; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.cloud.client.ServiceInstance; import org.springframework.cloud.client.discovery.DiscoveryClient; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import org.springframework.web.client.RestTemplate; //純手寫Ribbon本地負載均衡 @RestController public class ExtRibbonController { @Autowired private DiscoveryClient discoveryClient; @Autowired private RestTemplate restTemplate; //定義請求數 private int reqCount; @RequestMapping("/ribbonMember") public String ribbonMember() { //互毆去對應服務器遠程調用地址 String instanceUrl = getInstance()+"/getMember"; System.out.println("instanceUrl"+instanceUrl); //直接使用httpclient遠程調用。本次使用rest方式 String result = restTemplate.getForObject(instanceUrl, String.class); //底層使用httpclient實現的 return result; } private String getInstance() { List<ServiceInstance> instances = discoveryClient.getInstances("app-toov5-member"); if (instances==null || instances.size()==0) { return null; } int instanceSize = instances.size(); int serviceIndex = reqCount%instanceSize; reqCount++; return instances.get(serviceIndex).getUri().toString(); } }
啓動類:
package com.toov5.api.controller; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.netflix.eureka.EnableEurekaClient; import org.springframework.context.annotation.Bean; import org.springframework.web.client.RestTemplate; @SpringBootApplication @EnableEurekaClient public class AppOrder { public static void main(String[] args) { SpringApplication.run(AppOrder.class, args); } //解決RestTemplate找不到問題 把restTemplate註冊到Spring Boot容器中 @Bean // @LoadBalanced 手寫的 不要去實現本地負載均衡效果了 RestTemplate restTemplate() { return new RestTemplate(); } }
yml:
###服務啓動端口號 server: port: 8002 ###服務名稱(服務註冊到eureka名稱) spring: application: name: app-toov5-order ###服務註冊到eureka地址 eureka: client: service-url: defaultZone: http://127.0.0.1:8100/eureka ###由於該應用爲註冊中心,不會註冊本身 register-with-eureka: true ###是否須要從eureka上獲取註冊信息 fetch-registry: true
pom
<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.toov5</groupId> <artifactId>order</artifactId> <version>0.0.1-SNAPSHOT</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.1.RELEASE</version> </parent> <!-- 管理依賴 --> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Finchley.M7</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <dependencies> <!-- SpringBoot整合Web組件 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!-- SpringBoot整合eureka客戶端 --> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency> </dependencies> <!-- 注意: 這裏必需要添加, 否者各類依賴有問題 --> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/libs-milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> </project>
Eureka
pom
<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.toov5</groupId> <artifactId>SpringCloud-eureka-server</artifactId> <version>0.0.1-SNAPSHOT</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.1.RELEASE</version> </parent> <!-- 管理依賴 --> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Finchley.M7</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <dependencies> <!--SpringCloud eureka-server --> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId> </dependency> </dependencies> <!-- 注意: 這裏必需要添加, 否者各類依賴有問題 --> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/libs-milestone</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> </project>
yml
###eureka 服務端口號 server: port: 8100 ###服務註冊名稱 eureka: instance: ##註冊中心ip地址 hostname: 127.0.0.1 ###客戶端調用地址 client: serviceUrl: defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/ ###由於該應用爲註冊中心,不會註冊本身 (集羣設爲true) register-with-eureka: false ###由於本身爲註冊中心 ,不會去在該應用中的檢測服務 fetch-registry: false
package com.toov5; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer; @EnableEurekaServer //開啓註冊中心 @SpringBootApplication public class AppEureka { public static void main(String[] args) { SpringApplication.run(AppEureka.class, args); } }
啓動訪問: