SpringBoot Cloud是什么
Spring Cloud是一个分布式的整体解决方案。 Spring Cloud 为开发者提供了在
分布式系统（配置管理，服务发现，熔断，路由，微代理，控制总线，一次性token，全局琐， leader选举，分布式session，集群状态）中快速构建的工具，
使用Spring Cloud的开发者可以快速的启动服务或构建应用、同时能够快速和云平台资源进行对接。
SpringCloud分布式开发五大常用组件
• 服务发现——Netflix Eureka (发现了 英 [,jʊ(ə)'riːkə] )
• 客服端负载均衡——Netflix Ribbon (缎带 英 ['rɪbən] )
• 断路器——Netflix Hystrix (断路器)
• 服务网关——Netflix Zuul (路由网关)
• 分布式配置——Spring Cloud Config (配置)
https://www.processon.com/diagraming/5cef1a48e4b05d5b38bdb090
springboot和springcloud如果版本不兼容会报异常java.lang.NoSuchMethodError: org.springframework.boot.builder.SpringApplicationBuilder.
springcloud中eureka搭建
建一个空项目springboot-07-cloud,内有三个子模块
- eureka-server (注册中心)
- cloud-provider (服务提供者)
- cloud-consumer (消费者)
三个子模块文件结构如下
springboot-07-cloud base分支中三个子模块如下
| springboot-07-cloud中三个子模块 | eureka-server (注册中心) | cloud-provider (服务提供者) |
cloud-consumer (消费者) |
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| pom.xml区别 |
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>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>1.5.21.RELEASEversion>
<relativePath/>
parent>
<groupId>com.examplegroupId>
<artifactId>eureka-serverartifactId>
<version>0.0.1-SNAPSHOTversion>
<name>eureka-servername>
<description>Demo project for Spring Bootdescription>
<properties>
<java.version>1.8java.version>
<spring-cloud.version>Edgware.SR6spring-cloud.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
|
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>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>1.5.21.RELEASEversion>
<relativePath/>
parent>
<groupId>com.examplegroupId>
<artifactId>cloud-providerartifactId>
<version>0.0.1-SNAPSHOTversion>
<name>cloud-providername>
<description>Demo project for Spring Bootdescription>
<properties>
<java.version>1.8java.version>
<spring-cloud.version>Edgware.SR6spring-cloud.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>org.springframework.cloudgroupId>
<artifactId>spring-cloud-starter-netflix-eureka-clientartifactId>
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>${spring-cloud.version}version>
<type>pomtype>
<scope>importscope>
dependency>
dependencies>
dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
plugin>
plugins>
build>
project>
|
xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0modelVersion>
<parent>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-parentartifactId>
<version>1.5.21.RELEASEversion>
<relativePath/>
parent>
<groupId>com.examplegroupId>
<artifactId>cloud-consumerartifactId>
<version>0.0.1-SNAPSHOTversion>
<name>cloud-consumername>
<description>Demo project for Spring Bootdescription>
<properties>
<java.version>1.8java.version>
<spring-cloud.version>Edgware.SR6spring-cloud.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>org.springframework.cloudgroupId>
<artifactId>spring-cloud-starter-netflix-eureka-clientartifactId>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-testartifactId>
<scope>testscope>
dependency>
dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloudgroupId>
<artifactId>spring-cloud-dependenciesartifactId>
<version>${spring-cloud.version}version>
<type>pomtype>
<scope>importscope>
dependency>
dependencies>
dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-maven-pluginartifactId>
plugin>
plugins>
build>
project>
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| application.yml区别 |
server: port: 8761 eureka: instance: hostname: eureka-server # eureka实例主机名 client: register-with-eureka: false # 不把自己注册到eureka上, 因为自己本来就是注册中心 fetch-registry: false # 不从eureka上获取服务的注册信息 service-url: defaultZone: http://localhost:8761/eureka/ #defaultZone 是注册中心服务注册的地址
默认eureka服务注册中心也会将自己作为客户端来尝试注册它自己，所以我们需要禁用它的客户端注册行为,将register-with-eureka置为false 若未禁用eureka服务注册中心的客户端注册行为，需提供service-url注册中心地址 |
server: port: 8001 spring: application: name: provider eureka: instance: prefer-ip-address: true # 注册服务时使用服务的ip地址 client: register-with-eureka: true # 把自己注册到eureka上 fetch-registry: true # 从eureka上获取服务的注册信息 service-url: defaultZone: http://localhost:8761/eureka/ #defaultZone 是注册中心服务注册的地址
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server: port: 8002 spring: application: name: consumer eureka: instance: prefer-ip-address: true # 注册服务时使用服务的ip地址 client: register-with-eureka: true # 把自己注册到eureka上 fetch-registry: true # 从eureka上获取服务的注册信息 service-url: defaultZone: http://localhost:8761/eureka/ #defaultZone 是注册中心服务注册的地址
|
特别注意: springboot和springcloud的版本有对应要求, 本样例用的是
springboot
大版本对应：
| Spring Boot | Spring Cloud |
|---|---|
| 1.2.x | Angel版本 |
| 1.3.x | Brixton版本 |
| 1.4.x stripes | Camden版本 |
| 1.5.x | Dalston版本、Edgware版本 |
| 2.0.x | Finchley版本 |
在实际开发过程中，我们需要更详细的版本对应：
| spring-boot-starter-parent | spring-cloud-dependencies | ||||
|---|---|---|---|---|---|
| 版本号 | 发布日期 | 版本号 | 发布日期 | ||
| 1.5.2.RELEASE | 2017年3月 | 稳定版 | Dalston.RC1 | 2017年未知月 | |
| 1.5.9.RELEASE | 2017年11月 | 稳定版 | Edgware.RELEASE | 2017年11月 | 稳定版 |
| 1.5.16.RELEASE | Edgware.SR5 | ||||
| 1.5.20.RELEASE | Edgware.SR5 | ||||
| 2.0.2.RELEASE | 2018年5月 | Finchley.BUILD-SNAPSHOT | 2018年未知月 | ||
| 2.0.6.RELEASE | Finchley.SR2 | ||||
| 2.1.4.RELEASE | Greenwich.SR1 | ||||
| 待更新... | |
||||
eureka-server (注册中心)
EurekaServerApplication.java
注册中心启动入口 , 注意需要@EnableEurekaServer注解支持
package com.example.eurekaserver; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer; /** * 使用注册中心步骤 * 1. application.yml配置 * 2. @EnableEurekaServer注解添加 */ @SpringBootApplication @EnableEurekaServer public class EurekaServerApplication { public static void main(String[] args) { SpringApplication.run(EurekaServerApplication.class, args); } }
cloud-provider (服务提供者)
CloudProviderApplication.java
生产者启动类, 不需要额外注解, 因为做了注册到eureka上的配置, 就可以直接把@RestController注解的所有接口自动注册到eureka注册中心 , 供消费者调用.
package com.example.cloud.provider; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class CloudProviderApplication { public static void main(String[] args) { SpringApplication.run(CloudProviderApplication.class, args); } }
CloudProviderController.java
package com.example.cloud.provider.controller; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController; @RestController public class CloudProviderController { static int number; @GetMapping("/buyTicket") public String buyTicker(){ return "ticker "+ ++number; } }
cloud-consumer (消费者)
CloudConsumerApplication.java
消费者启动入口 , 注意需要开启@EnableDiscoveryClient注解
package com.example.cloud.consumer; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.client.discovery.EnableDiscoveryClient; /** * cloud 客户端调用时需要引入 @EnableDiscoveryClient 注解 */ @SpringBootApplication @EnableDiscoveryClient public class CloudConsumerApplication { public static void main(String[] args) { SpringApplication.run(CloudConsumerApplication.class, args); } }
MyConfiguration.java
需要把RestTemplate类组装到springboot容器中, 专门用于调用eureka上发现的服务
package com.example.cloud.consumer.config; import org.springframework.cloud.client.loadbalancer.LoadBalanced; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.web.client.RestTemplate; @Configuration public class MyConfiguration { @LoadBalanced//负载均衡 @Bean//需要把RestTemplate装配进来,专门用于调用Eureka上发现的服务 public RestTemplate restTemplate() { return new RestTemplate(); } }
CloudConsumberController.java
使用 http://localhost:8002/buyTicket 访问
package com.example.cloud.consumer.controller; import com.netflix.discovery.converters.Auto; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.cloud.client.loadbalancer.LoadBalanced; import org.springframework.context.annotation.Bean; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RestController; import org.springframework.web.client.RestTemplate; @RestController public class CloudConsumberController { @Autowired RestTemplate restTemplate; //http://localhost:8002/buyTicket @GetMapping("/buyTicket") public String buyTicker(){ String retData = restTemplate.getForObject("http://PROVIDER/buyTicket",String.class);// retData = "成功购买" + retData; return retData; } }
访问
访问springcloud的eureka-server 注册中心 http://localhost:8761/
访问cloud-consumer消费者提供的controller接口 http://localhost:8002/buyTicket 后,浏览器显示如下
成功购买ticker 1
注意Status一栏显示的是服务实例名, 默认取名规则为${spring.cloud.client.hostname}:${spring.application.name}:${spring.application.instance_id:${server.port}} , 最后的写法意为如果spring.application.instance_id没有定义,则取server.port, 如果已定义了则舍掉server.port取spring.application.instance_id
遗留问题
defaultZone 需要添加/eureka后缀? 是的默认就这样.
我的git项目地址
https://gitee.com/KingBoBo/springboot-07-cloud base分支
进阶篇
SpringBoot SpringCloud集群==>https://www.cnblogs.com/whatlonelytear/p/10894161.html