springclould的入门

首先以下所有的东西都是我个人的一些见解,如果有什么不足,欢迎补充

springclould是一个以微服务著名的框架,springclould是把RESTful接口作为服务提供了出去.

这是我在码云上拉下来的一个springclould的demo.

地址:http://git.oschina.net/weiyonghua/spring-clould-action

这是一个整体的结构,下面分开来一个一个介绍.

1.eureka-server 这个是springclould的注册中心

单个项目结构如下

pom依赖

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>4.0.0modelVersion>

   <groupId>com.examplegroupId>
   <artifactId>eureka-serverartifactId>
   <version>0.0.1-SNAPSHOTversion>
   <packaging>jarpackaging>

   <name>eureka-servername>
   <description>Demo project for Spring Bootdescription>

   <parent>
      <groupId>com.examplegroupId>
      <artifactId>spring-clould-actionartifactId>
      <version>0.0.1-SNAPSHOTversion>
   parent>

   <properties>
      <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
      <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>
      <java.version>1.7java.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>

   <build>
      <plugins>
         <plugin>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-maven-pluginartifactId>
         plugin>
      plugins>
   build>


project>

application.properties的配置如下

#服务注册中心端口号
server.port=1111
#是否向服务注册中心注册自己
eureka.client.register-with-eureka=false
#是否检索服务
eureka.client.fetch-registry=false
#服务注册中心的配置内容，指定服务注册中心的位置
eureka.client.serviceUrl.defaultZone=http://localhost:${server.port}/eureka/

application-peer1.properties

#springclould的项目标识
spring.application.name=eureka-server
server.port=1111
#设置当前实例的主机名称
eureka.instance.hostname=peer1
#服务注册中心的配置内容,指定服务注册中心的位置
eureka.client.serviceUrl.defaultZone=http://peer2:1112/eureka/

application-peer2.properties

#springclould的项目标识
spring.application.name=eureka-server
server.port=1112
#设置当前实例的主机名称
eureka.instance.hostname=peer2
#服务注册中心的配置内容，指定服务注册中心的位置
eureka.client.serviceUrl.defaultZone=http://peer1:1111/eureka/

上述两个文件的配置是做一个注册中心的小集群,eureka.instance.hostname这个配置需要添加到你的hosts文件中

127.0.0.1  peer1

127.0.0.1  peer2

EurekaServerApplication 启动类

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;

@EnableEurekaServer//注册一个服务中心
@SpringBootApplication
public class EurekaServerApplication {

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

2.computer-service 服务提供方

单个项目结构如下

pom依赖

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>4.0.0modelVersion>

   <groupId>com.examplegroupId>
   <artifactId>computer-serviceartifactId>
   <version>0.0.1-SNAPSHOTversion>
   <packaging>jarpackaging>

   <name>computer-servicename>
   <description>Demo project for Spring Bootdescription>

   <parent>
      <groupId>com.examplegroupId>
      <artifactId>spring-clould-actionartifactId>
      <version>0.0.1-SNAPSHOTversion>
   parent>

   <properties>
      <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
      <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>
      <java.version>1.7java.version>
   properties>

   <dependencies>
      <dependency>
         <groupId>org.springframework.cloudgroupId>
         <artifactId>spring-cloud-starter-eurekaartifactId>
      dependency>

      <dependency>
         <groupId>org.springframework.bootgroupId>
         <artifactId>spring-boot-starter-testartifactId>
         <scope>testscope>
      dependency>
   dependencies>

   <build>
      <plugins>
         <plugin>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-maven-pluginartifactId>
         plugin>
      plugins>
   build>


project>

application.properties的文件配置

#springclould的项目标识
spring.application.name=computer-service
server.port=2222
#服务注册中心的配置内容,指定服务注册中心的位置
eureka.client.serviceUrl.defaultZone=http://peer1:1111/eureka/,http://peer2:1111/eureka/

 注意客户端和服务端必须注册在同一个注册中心,这里的项目标识就是下面客户端调用的依据

ComputeController这个类中是一些简单的方法实现

package com.example.demo.controller;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

/**
 * Created by weiyonghua on 2017/6/30.
 */
@RestController
public class ComputeController {

    private final Logger logger = LoggerFactory.getLogger(getClass());

    @Autowired
    private DiscoveryClient client;

    @RequestMapping(value = "/add" ,method = RequestMethod.GET)
    public Integer add(@RequestParam Integer a, @RequestParam Integer b) {
        ServiceInstance instance = client.getLocalServiceInstance();
        Integer r = a + b;
        logger.info("/add, host:" + instance.getHost() + ", service_id:" + instance.getServiceId() + ", result:" + r);
        return r;
    }
}

ServiceProviderApplication 启动类

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

@SpringBootApplication
@EnableDiscoveryClient//向服务中心注册
public class ServiceProviderApplication {

   public static void main(String[] args) {
      SpringApplication.run(ServiceProviderApplication.class, args);
   }
}

3.feign-consumer 客户端

单个项目结构如下

pom 依赖如下

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>4.0.0modelVersion>

   <groupId>com.examplegroupId>
   <artifactId>feign-consumerartifactId>
   <version>0.0.1-SNAPSHOTversion>
   <packaging>jarpackaging>

   <name>feign-consumername>
   <description>Demo project for Spring Bootdescription>

   <parent>
      <groupId>com.examplegroupId>
      <artifactId>spring-clould-actionartifactId>
      <version>0.0.1-SNAPSHOTversion>
      <relativePath/> 
   parent>

   <properties>
      <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
      <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>
      <java.version>1.7java.version>
   properties>

   <dependencies>
      <dependency>
         <groupId>org.springframework.cloudgroupId>
         <artifactId>spring-cloud-starter-feignartifactId>
      dependency>
      <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>

   <build>
      <plugins>
         <plugin>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-maven-pluginartifactId>
         plugin>
      plugins>
   build>


project>

ComputeClient 客户端调用类

package com.example.demo.service;

import org.springframework.cloud.netflix.feign.FeignClient;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

/**
 * Created by weiyonghua on 2017/6/30.
 */
@FeignClient(value = "compute-service" , fallback = ComputeClientHystrix.class)
public interface ComputeClient {

    @RequestMapping(method = RequestMethod.GET, value = "/add")
    Integer add(@RequestParam(value = "a") Integer a, @RequestParam(value = "b") Integer b);
}

@FeignClient 标签中的value/name都可以表示调用那个项目,对应上服务端的spring.application.name且在同一个注册中心上,并且路径和服务端的路径一致的时候就可以完成调用,fallback表示当这个服务调用失败的时候去调用的类,相当于不会在调用时出现服务直接挂掉的情况,给了一个缓冲.

ComputeClientHystrix  类

package com.example.demo.service;

import org.springframework.stereotype.Component;

/**
 * Created by weiyonghua on 2017/6/30.
 */
@Component
public class ComputeClientHystrix implements ComputeClient {
    @Override
    public Integer add(Integer a, Integer b) {
        return -9999;
    }
}

application.properties 配置类

spring.application.name=feign-consumer
server.port=4444
eureka.client.serviceUrl.defaultZone=http://localhost:1111/eureka/

FeignConsumerApplication 启动类

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.netflix.feign.EnableFeignClients;

@SpringBootApplication
@EnableDiscoveryClient//向服务中心注册
@EnableFeignClients//开启客户端的功能
public class FeignConsumerApplication {

   public static void main(String[] args) {
      SpringApplication.run(FeignConsumerApplication.class, args);
   }
}

ConsumerController 类 正常调用service方法即可

package com.example.demo.controller;

import com.example.demo.service.ComputeClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

/**
 * Created by weiyonghua on 2017/6/30.
 */
@RestController
public class ConsumerController {

    @Autowired
    ComputeClient computeClient;

    @RequestMapping(value = "/add", method = RequestMethod.GET)
    public Integer add() {
        return computeClient.add(10, 20);
    }
}

至此,springclould的基本调用就结束了,有兴趣深入了解的可以点击下面的链接

点击打开链接