同一份代码,改变端口,就可以启动多个同名但是端口不一样的微服务。
客户端通过nginx来调用后面的多个用户微服务来实现负载均衡,这是服务端负载均衡。
客户端有一个组件,可以知道当前有几个用户微服务的ip和端口,客户端实现一个负载均衡算法,直接去调用用户微服务。Ribbon是实现了客户端负载均衡的组件。
Ribbon选择一个在同一个zone且负载少的eureka,从中拉取可用的服务提供者列表,放到客户端,然后在客户端实现一个负载均衡的算法,最后命中到某个节点。Ribbon提供了多种算法:轮询、随机、根据响应时间。默认负载均衡的策略是轮询。
通过代码自定义配置ribbon:
package com.itmuch.cloud;
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.cloud.netflix.ribbon.RibbonClient;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.FilterType;
import org.springframework.web.client.RestTemplate;
@SpringBootApplication
@EnableEurekaClient
@RibbonClient(name = "microservice-provider-user", configuration = TestConfiguration.class)
//@ComponentScan扫的是他所在的包和子包
@ComponentScan(excludeFilters = { @ComponentScan.Filter(type = FilterType.ANNOTATION, value = ExcludeFromComponentScan.class) })
public class ConsumerMovieRibbonApplication {
@Bean
@LoadBalanced//就一个注解。@LoadBalanced整合了ribbon,让RestTemplate具备负载均衡的能力
public RestTemplate restTemplate() {
return new RestTemplate();
}
public static void main(String[] args) {
SpringApplication.run(ConsumerMovieRibbonApplication.class, args);
}
}
package com.itmuch.cloud;
public @interface ExcludeFromComponentScan {
}
package com.itmuch.cloud;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import com.netflix.loadbalancer.IRule;
import com.netflix.loadbalancer.RandomRule;
@Configuration
@ExcludeFromComponentScan//否则所有的ribbon客户端都会使用RandomRule这个规则
public class TestConfiguration {
// @Autowired
// IClientConfig config;
@Bean
public IRule ribbonRule() {
return new RandomRule(); //随机选取一个微服务,也可以自己定义路由规则。
}
}
package com.itmuch.cloud.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import com.itmuch.cloud.entity.User;
@RestController
public class MovieController {
@Autowired
private RestTemplate restTemplate;
@Autowired
private LoadBalancerClient loadBalancerClient;
@GetMapping("/movie/{id}")
public User findById(@PathVariable Long id) {
// http://localhost:7900/simple/,microservice-provider-user是注册到eureka之后的一个虚拟主机名(页面有,microservice-provider-user工程的虚拟主机名)。
//microservice-provider-user工程的配置文件中spring.application.name中定义。
// VIP virtual IP。不再是通过服务提供者的ip和端口访问了。
// HAProxy Heartbeat
//spring:application:name:microservice-provider-user
return this.restTemplate.getForObject("http://microservice-provider-user/simple/" + id, User.class);
}
@GetMapping("/test")
public String test() {
//如果microservice-provider-user微服务有多个,可以看出命中的是哪个ip端口
ServiceInstance serviceInstance = this.loadBalancerClient.choose("microservice-provider-user");
System.out.println("111" + ":" + serviceInstance.getServiceId() + ":" + serviceInstance.getHost() + ":" + serviceInstance.getPort());
ServiceInstance serviceInstance2 = this.loadBalancerClient.choose("microservice-provider-user2");
System.out.println("222" + ":" + serviceInstance2.getServiceId() + ":" + serviceInstance2.getHost() + ":" + serviceInstance2.getPort());
return "1";
}
}
spring:
application:
name: microservice-consumer-movie-ribbon #自己的工程名字
server:
port: 8010
eureka:
client:
healthcheck:
enabled: true
serviceUrl:
defaultZone: http://user:password123@localhost:8761/eureka #eureka server的地址
instance:
prefer-ip-address: true
<?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>
<artifactId>microservice-consumer-movie-ribbon</artifactId>
<packaging>jar</packaging>
<parent>
<groupId>com.itmuch.cloud</groupId>
<artifactId>microservice-spring-cloud</artifactId>
<version>0.0.1-SNAPSHOT</version>
</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-web</artifactId>
</dependency>
<!-- ribbon注册到eureka上面去 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
</project>
通过配置文件自定义ribbon:
package com.itmuch.cloud;
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 ConsumerMovieRibbonApplication {
@Bean
@LoadBalanced//就一个注解。@LoadBalanced整合了ribbon,让RestTemplate具备负载均衡的能力
public RestTemplate restTemplate() {
return new RestTemplate();
}
public static void main(String[] args) {
SpringApplication.run(ConsumerMovieRibbonApplication.class, args);
}
}
package com.itmuch.cloud.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import com.itmuch.cloud.entity.User;
@RestController
public class MovieController {
@Autowired
private RestTemplate restTemplate;
@Autowired
private LoadBalancerClient loadBalancerClient;
@GetMapping("/movie/{id}")
public User findById(@PathVariable Long id) {
// http://localhost:7900/simple/
// VIP virtual IP
// HAProxy Heartbeat
ServiceInstance serviceInstance = this.loadBalancerClient.choose("microservice-provider-user");
System.out.println("===" + ":" + serviceInstance.getServiceId() + ":" + serviceInstance.getHost() + ":" + serviceInstance.getPort());
return this.restTemplate.getForObject("http://microservice-provider-user/simple/" + id, User.class);
}
@GetMapping("/test")
public String test() {
ServiceInstance serviceInstance = this.loadBalancerClient.choose("microservice-provider-user");
System.out.println("111" + ":" + serviceInstance.getServiceId() + ":" + serviceInstance.getHost() + ":" + serviceInstance.getPort());
ServiceInstance serviceInstance2 = this.loadBalancerClient.choose("microservice-provider-user2");
System.out.println("222" + ":" + serviceInstance2.getServiceId() + ":" + serviceInstance2.getHost() + ":" + serviceInstance2.getPort());
return "1";
}
}
spring:
application:
name: microservice-consumer-movie-ribbon
server:
port: 8010
eureka:
client:
healthcheck:
enabled: true
serviceUrl:
defaultZone: http://user:password123@localhost:8761/eureka
instance:
prefer-ip-address: true
microservice-provider-user: #请求这个微服务的时候
ribbon: #ribbon配置
NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule #随机的rule去负载均衡
<?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>
<artifactId>microservice-consumer-movie-ribbon-properties-customizing</artifactId>
<packaging>jar</packaging>
<parent>
<groupId>com.itmuch.cloud</groupId>
<artifactId>microservice-spring-cloud</artifactId>
<version>0.0.1-SNAPSHOT</version>
</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-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
</project>
Ribbon禁止eureka:
package com.itmuch.cloud;
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 ConsumerMovieRibbonApplication {
@Bean
@LoadBalanced
public RestTemplate restTemplate() {
return new RestTemplate();
}
public static void main(String[] args) {
SpringApplication.run(ConsumerMovieRibbonApplication.class, args);
}
}
package com.itmuch.cloud.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.loadbalancer.LoadBalancerClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import com.itmuch.cloud.entity.User;
@RestController
public class MovieController {
@Autowired
private RestTemplate restTemplate;
@Autowired
private LoadBalancerClient loadBalancerClient;
@GetMapping("/movie/{id}")
public User findById(@PathVariable Long id) {
// http://localhost:7900/simple/
// VIP virtual IP
// HAProxy Heartbeat
ServiceInstance serviceInstance = this.loadBalancerClient.choose("microservice-provider-user");
System.out.println("===" + ":" + serviceInstance.getServiceId() + ":" + serviceInstance.getHost() + ":" + serviceInstance.getPort());
return this.restTemplate.getForObject("http://microservice-provider-user/simple/" + id, User.class);
}
@GetMapping("/test")
public String test() {
ServiceInstance serviceInstance = this.loadBalancerClient.choose("microservice-provider-user");
System.out.println("111" + ":" + serviceInstance.getServiceId() + ":" + serviceInstance.getHost() + ":" + serviceInstance.getPort());
ServiceInstance serviceInstance2 = this.loadBalancerClient.choose("microservice-provider-user2");
System.out.println("222" + ":" + serviceInstance2.getServiceId() + ":" + serviceInstance2.getHost() + ":" + serviceInstance2.getPort());
return "1";
}
}
spring:
application:
name: microservice-consumer-movie-ribbon
server:
port: 8010
eureka:
client:
healthcheck:
enabled: true
serviceUrl:
defaultZone: http://user:password123@localhost:8761/eureka
instance:
prefer-ip-address: true
ribbon:
eureka:
enabled: false #禁止ribbon中的eureka
microservice-provider-user: #请求这个微服务的时候(此时这个微服务有7900.7901.7904三个微服务),只访问7900
ribbon:
listOfServers: localhost:7900
<?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>
<artifactId>microservice-consumer-movie-ribbon-without-eureka</artifactId>
<packaging>jar</packaging>
<parent>
<groupId>com.itmuch.cloud</groupId>
<artifactId>microservice-spring-cloud</artifactId>
<version>0.0.1-SNAPSHOT</version>
</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-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
</project>