SpringCloud之Eureka服务注册中心,服务注册和服务发现

今天药忘吃喽~ 2022-05-19 02:08 347阅读 0赞

我使用的版本

springboot版本
    <version>1.5.14.RELEASE</version>
     springcloud版本
    <spring-cloud.version>Edgware.SR4</spring-cloud.version>

使用eureka写一个注册中心,相当于zookeeper的地位  
引入eurekaServer 的依赖

<dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-eureka-server</artifactId>
            </dependency>

配置eurekaServer

server:
      port: 8761
    eureka:
      instance:
        hostname: eureka-server
      client:
        register-with-eureka: false
        fetch-registry: false
        service-url:
          defaultZone: http://localhost:8761/eureka/ #默认配置

@EnableEurekaServer,启动eurekaServer

@EnableEurekaServer
    @SpringBootApplication
    public class Server3Application { 
    
        public static void main(String[] args) {
            SpringApplication.run(Server3Application.class, args);
        }
    }

访问[http://localhost:8761/][http_localhost_8761] 出现eurekaServer注册中心的界面

写provider,多复制几个,改一下端口号

<dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-eureka</artifactId>
            </dependency>

server:
      port: 8001
    spring:
      application:
        name: provider-ticket
    eureka:
      instance:
        prefer-ip-address: true # 注册服务的时候使用服务的ip地址
      client:
        service-url:
          defaultZone: http://localhost:8761/eureka/

使用RestAPI提供服务

@RestController
    public class UserController { 
    
        @GetMapping("/ticket")
        public String test(){
            System.out.println("===================>8001");
            return "8001 provider";
        }
    }

写一个消费者  
引入依赖

<dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-eureka</artifactId>
            </dependency>

配置消费者

spring:
      application:
        name: consumer-user
    server:
      port: 8100
    eureka:
      instance:
        prefer-ip-address: true # 注册服务的时候使用服务的ip地址
      client:
        service-url:
          defaultZone: http://localhost:8761/eureka/

发现服务@EnableDiscoveryClient  
配置一个RestTemplate,并启动负债均衡@LoadBalanced  
启动消费者

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

访问该consumer自动远程调用provider

@RestController
    public class UserController { 
    
        @Autowired
        RestTemplate restTemplate;
    
        @GetMapping("/buy")
        public String test() {
            System.out.println("===========================>8100");
            String forObject = restTemplate.getForObject("http://PROVIDER-TICKET/ticket", String.class);
            System.out.println(forObject);
            return forObject;
        }
    
    }

访问localhost://8761可以看到注册中心中有两个服务提供者和一个服务消费者  
![这里写图片描述][70]

访问[http://localhost:8100/buy][http_localhost_8100_buy]  
会发现界面轮流出现8001 provider,8002 provider,启动了负债均衡

[http_localhost_8761]: http://localhost:8761/
[70]: /images/20220519/7d5e160aeb7f401881e7f88a03918e42.png
[http_localhost_8100_buy]: http://localhost:8100/buy