Spring Cloud 学习笔记-搭建微信h5牛牛棋牌房卡平台开发应用

微信h5牛牛棋牌房卡平台开发(Q-1687054422)提供基于REST的服务，在集群中主要用于服务管理。Eureka提供了基于Java语言的客户端组件，客户端组件实现了负载均衡的功能，为业务组件的集群部署创造了条件。使用该框架，可以将业务组件注册到Eureka容器中，这些业务组件可进行集群部署，Eureka主要维护这些服务的列表并自动检查它们的状态。

程序结构

创建Eureka Server

maven依赖

<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Dalston.SR1</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>

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

在application.yml 更改spring boot 启动端口

server:
port: 8761

开启Eureka服务注解 @EnableEurekaServer

@EnableEurekaServer
@SpringBootApplication
public class EKServerApplication {

public static void main(String[] args) {
new SpringApplicationBuilder(EKServerApplication.class).run(args);
}
}

启动springboot

[Thread-11] o.s.c.n.e.server.EurekaServerBootstrap: Initialized server context
[main] s.b.c.e.t.TomcatEmbeddedServletContainer: Tomcat started on port(s): 8761 (http)
[main] .s.c.n.e.s.EurekaAutoServiceRegistration: Updating port to 8761
[main] c.b.firstEkServer.EKServerApplication: Started EKServerApplication in 8.594 seconds (JVM running for 9.523)

启动期间会出现一个无法连接到服务器的异常 这个是由于Eureka在启动的时候会把自己当作一个客户端去服务器抓取注册信息

com.netflix.discovery.shared.transport.TransportException: Cannot execute request on any known server

增加如下配置启动时便不
bde8
会再出现该异常

eureka:
client:
registerWithEureka: false
fetchRegistry: false

registerWithEureka 声明是否将自己的信息注册到Eureka服务器，默认值为true。
fetchRegistry 声明是否到Eureka服务器中抓取注册信息，默认值为true。
在浏览器中访问 http://localhost:8761 查看Eureka控制台

创建服务提供者

依赖

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

在 application.yml 中配置端口、Eureka实例名称和Eureka服务地址

server:
port: 8080
spring:
application:
name: ek-provider
eureka:
instance:
hostname: localhost
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/

创建一个简单的 REST 服务

@RestController
public class HelloController {

@RequestMapping("/hello")
public String hello(HttpServletRequest request) {
return "hello:" + request.getRequestURL();
}
}

开启Eureka客户端注解 @EnableEurekaServer

@EnableEurekaClient
@SpringBootApplication
public class EkProviderApplication {

public static void main(String[] args) {
new SpringApplicationBuilder(EkProviderApplication.class).run(args);

}
}

启动之后在 Eureka 控制台可以看到服务提供者已经在 Eureka 中注册

创建服务调用者

依赖

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

在 application.yml 中配置端口、Eureka实例名称和Eureka服务地址

server:
port: 9000
spring:
application:
name: ek-invoke
eureka:
instance:
hostname: localhost
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/

编写一个 REST 服务 调用服务提供者的 “/hello”