springclound提供rpc为各微服务模块进行调用，eureka为注册中心-rpc为feign 默认就集成了ribbon（负载均衡客户端）

具体代码在E:\学习文档子目录压缩\框架\微服务相关\springcloud\springclound提供rpc为各微服务模块进行调用，eureka为注册中心\springclound提供rpc为各微服务模块进行调用，eureka为注册中心-rpc为feign 默认就集成了ribbon（负载均衡客户端）或

我的网盘\我的笔记\学习文档子目录压缩\框架\微服务相关\springcloud\springclound提供rpc为各微服务模块进行调用，eureka为注册中心\springclound提供rpc为各微服务模块进行调用，eureka为注册中心-rpc为feign 默认就集成了ribbon（负载均衡客户端）

 

 

1.先开注册中心 EurekaServer，在开两个服务提供者eurekaclient (一个端口8762，一个端口8763)，在开服务消费者服务 serice-feign，然后去注册中心看下，效果如下

 

2.请求service-ribbon 服务看负载效果

 

 

 

 

 

 

4.1 服务注册

4.1.1创建eurekaserver 项目

4.1.2引入maven依赖

<parent>             <groupId>org.springframework.bootgroupId>             <artifactId>spring-boot-starter-parentartifactId>             <version>1.5.2.RELEASEversion>             <relativePath />       parent>       <properties>             <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>             <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>             <java.version>1.8java.version>       properties>         <dependencies>                         <dependency>                   <groupId>org.springframework.cloudgroupId>                   <artifactId>spring-cloud-starter-eureka-serverartifactId>             dependency>                         <dependency>                   <groupId>org.springframework.bootgroupId>                   <artifactId>spring-boot-starter-testartifactId>                   <scope>testscope>             dependency>       dependencies>       <dependencyManagement>             <dependencies>                   <dependency>                        <groupId>org.springframework.cloudgroupId>                        <artifactId>spring-cloud-dependenciesartifactId>                        <version>Dalston.RC1version>                        <type>pomtype>                        <scope>importscope>                   dependency>             dependencies>       dependencyManagement>       <build>             <plugins>                   <plugin>                        <groupId>org.springframework.bootgroupId>                        <artifactId>spring-boot-maven-pluginartifactId>                   plugin>             plugins>       build>       <repositories>             <repository>                   <id>spring-milestonesid>                   <name>Spring Milestonesname>                   <url>https://repo.spring.io/milestoneurl>                   <snapshots>                        <enabled>falseenabled>                   snapshots>             repository>       repositories>

 

4.3配置application.yml

server:   port: 8761 eureka:   instance:     hostname: localhost   client:     registerWithEureka: false     fetchRegistry: false     serviceUrl:       defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/

 

4.4启动EurekaServer

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

1. eureka.client.registerWithEureka=true  #是否将自身注册  
2. eureka.client.fetchRegistry=false    #如果为true，启动时报警. 

4.5打开eureka server 界面的

http://localhost:8761 ,界面如下：   No application available 没有服务被发现 ……^_^  因为没有注册服务当然不可能有服务被发现了。

 

4.2 服务提供者

创建一个服务提供者 (eureka client),当client向server注册时，它会提供一些元数据，例如主机和端口，URL，主页等。Eureka server 从每个client实例接收心跳消息。 如果心跳超时，则通常将该实例从注册server中删除。

 

4.2.1 创建项目eurekaclient

4.2.2 引入maven依赖

<parent>        <groupId>org.springframework.bootgroupId>        <artifactId>spring-boot-starter-parentartifactId>         <version>1.5.2.RELEASEversion>        <relativePath />     parent>     <properties>        <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>         <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>        <java.version>1.8java.version>     properties>     <dependencies>        <dependency>            <groupId>org.springframework.cloudgroupId>            <artifactId>spring-cloud-starter-eurekaartifactId>        dependency>        <dependency>            <groupId>org.springframework.bootgroupId>            <artifactId>spring-boot-starter-webartifactId>        dependency>        <dependency>            <groupId>org.springframework.bootgroupId>            <artifactId>spring-boot-starter-testartifactId>            <scope>testscope>        dependency>     dependencies>     <dependencyManagement>        <dependencies>            <dependency>               <groupId>org.springframework.cloudgroupId>               <artifactId>spring-cloud-dependenciesartifactId>               <version>Dalston.RC1version>               <type>pomtype>               <scope>importscope>            dependency>        dependencies>     dependencyManagement>     <build>        <plugins>            <plugin>               <groupId>org.springframework.bootgroupId>               <artifactId>spring-boot-maven-pluginartifactId>            plugin>        plugins>     build>     <repositories>        <repository>            <id>spring-milestonesid>            <name>Spring Milestonesname>            <url>https://repo.spring.io/milestoneurl>            <snapshots>               <enabled>falseenabled>            snapshots>        repository>     repositories>

4.2.3 application.yml配置

eureka:   client:     serviceUrl:       defaultZone: http://localhost:8761/eureka/ server:   port: 8762 spring:   application:     name: service-hi

 

4.2.4 发布服务

通过注解@EnableEurekaClient 表明自己是一个eurekaclient.

 

@SpringBootApplication @EnableEurekaClient @RestController public class ServiceHiApplication {        public static void main(String[] args) {           SpringApplication.run(ServiceHiApplication.class, args);      }        @Value("${server.port}")      String port;        @RequestMapping("/hi")      public String home(@RequestParam String name) {           return "hi " + name + ",i am from port:" + port;      }   }

4.2.5 演示效果

需要指明spring.application.name,这个很重要，这在以后的服务与服务之间相互调用一般都是根据这个name 。 
启动工程，打开http://localhost:8761 ，即eureka server 的网址：

 

你会发现一个服务已经注册在服务中了，服务名为SERVICE-HI ,端口为7862

这时打开 http://localhost:8762/hi?name=forezp ，你会在浏览器上看到 :

hi forezp,i am from port:8762

• 服务消费者（Feign）

6.1 什么是Feign

Feign是一个声明式的伪Http客户端，它使得写Http客户端变得更简单。使用Feign，只需要创建一个接口并注解。它具有可插拔的注解特性，可使用Feign 注解和JAX-RS注解。Feign支持可插拔的编码器和解码器。Feign默认集成了Ribbon，并和Eureka结合，默认实现了负载均衡的效果。

简而言之：

• Feign 采用的是基于接口的注解
• Feign 整合了ribbon

6.2 准备工作

继续用上一节的工程， 启动eureka-server，端口为8761; 启动service-hi 两次，端口分别为8762 、8773.

6.2.1 准备工创建一个feign的服务

新建一个spring-boot工程，取名为serice-feign，在它的pom文件引入Feign的起步依赖spring-cloud-starter-feign、Eureka的起步依赖spring-cloud-starter-eureka、Web的起步依赖spring-boot-starter-web，代码如下：

 

<parent>         <groupId>org.springframework.bootgroupId>         <artifactId>spring-boot-starter-parentartifactId>         <version>1.5.2.RELEASEversion>         <relativePath/>     parent>       <properties>         <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>         <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>         <java.version>1.8java.version>     properties>       <dependencies>         <dependency>             <groupId>org.springframework.cloudgroupId>             <artifactId>spring-cloud-starter-eurekaartifactId>         dependency>         <dependency>             <groupId>org.springframework.cloudgroupId>             <artifactId>spring-cloud-starter-feignartifactId>         dependency>         <dependency>             <groupId>org.springframework.bootgroupId>             <artifactId>spring-boot-starter-webartifactId>         dependency>           <dependency>             <groupId>org.springframework.bootgroupId>             <artifactId>spring-boot-starter-testartifactId>             <scope>testscope>         dependency>     dependencies>       <dependencyManagement>         <dependencies>             <dependency>                 <groupId>org.springframework.cloudgroupId>                 <artifactId>spring-cloud-dependenciesartifactId>                 <version>Dalston.RC1version>                 <type>pomtype>                 <scope>importscope>             dependency>         dependencies>     dependencyManagement>       <build>         <plugins>             <plugin>                 <groupId>org.springframework.bootgroupId>                 <artifactId>spring-boot-maven-pluginartifactId>             plugin>         plugins>     build>       <repositories>         <repository>             <id>spring-milestonesid>             <name>Spring Milestonesname>             <url>https://repo.spring.io/milestoneurl>             <snapshots>                 <enabled>falseenabled>             snapshots>         repository>     repositories>

6.2.2 application.yml配置

在工程的配置文件application.yml文件，指定程序名为service-feign，端口号为8765，服务注册地址为http://localhost:8761/eureka/ ，代码如下：

eureka:   client:     serviceUrl:       defaultZone: http://localhost:8761/eureka/ server:   port: 8765 spring:   application:     name: service-feign

 

6.2.3 定义一个feign接口

@FeignClient(value = "service-hi") public interface SchedualServiceHi {      @RequestMapping(value = "/hi", method = RequestMethod.GET)      String sayHiFromClientOne(@RequestParam(value = "name") String name); }

6.2.4一个”/hi”的API接口

@RestController public class HiController {     @Autowired     SchedualServiceHi schedualServiceHi;     @RequestMapping(value = "/hi",method = RequestMethod.GET)     public String sayHi(@RequestParam String name){         return schedualServiceHi.sayHiFromClientOne(name);     } }

6.2.5启动方式

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

 

6.2.6 演示效果

启动程序，多次访问http://localhost:8765/hi?name=forezp,浏览器交替显示： hi forezp,i am from port:8762 hi forezp,i am from port:8763