SpringCloud 服务治理
作者:互联网
1. Eureka
1.1 Eureka 介绍
Eureka 是 Netflix 公司开源的一个服务注册与发现的组件。
• Eureka 和其他 Netflix 公司的服务组件(例如负载均衡、熔断器、网关等) 一起,被 SpringCloud 社区整合为 Spring-Cloud-Netflix 模块。
• Eureka 包含两个组件:Eureka Server(注册中心)和 Eureka Client(服务提供者、服务消费者)。
1.2 Eureka 快速入门
搭建步骤:
- 搭建 Provider 和 Consumer 服务。
- 使用 RestTemplate 完成远程调用。
- 搭建 Eureka Server 服务。
- 改造 Provider 和 Consumer,成为 Eureka Client。
- Consumer 服务通过从 Eureka Server 中抓取 Provider 地址,完成远程调用。
父工程
<?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>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>eureka-parent</artifactId>
<packaging>pom</packaging>
<version>1.0-SNAPSHOT</version>
<modules>
<module>eureka-provider</module>
<module>eureka-consumer</module>
<module>eureka-server</module>
</modules>
<parent>
<!-- spring boot 环境 -->
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.0.RELEASE</version>
</parent>
<dependencies>
<!-- 简化POJO -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
<!-- Spring Cloud 依赖管理 -->
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<!--spring cloud 版本-->
<spring-cloud.version>Greenwich.RELEASE</spring-cloud.version>
</properties>
</project>
Eureka Server(子工程)
pom.xml
<?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">
<parent>
<artifactId>eureka-parent</artifactId>
<groupId>org.example</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>eureka-server</artifactId>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- eureka-server -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
</dependencies>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
</properties>
</project>
启动类
package com;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
@SpringBootApplication
@EnableEurekaServer // 启用 EurekaServer(不声明也是默认启动)
public class EurekaApp {
public static void main(String[] args) {
SpringApplication.run(EurekaApp.class, args);
}
}
application.yml
server:
port: 8761
# eureka 配置:共分为四部分配置
# 1. dashboard: eureka 的 web 控制台配置
# 2. server: eureka 的服务端配置
# 3. client: eureka 的客户端配置
# 4. instance: eureka 的实例配置
eureka:
instance:
hostname: localhost # 主机名
client:
service-url:
defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka # eureka 服务端地址,将来客户端使用该地址和 eureka 进行通信
register-with-eureka: false # 是否将自己的路径注册到 eureka 上(eureka server 需要;eureka provider client 不需要)。默认:true
fetch-registry: false # 是否需要从 eureka 中抓取路径(eureka server 不需要;eureka consumer client 需要)。默认:true
Eureka 控制台
运行启动类后,访问 localhost:8761 即可进入Eureka 控制台:
- System status:系统状态信息
- DS Replicas:集群信息
- tance currently registered with Eureka:实例注册信息
- General Info:通用信息
- Instance Info:实例信息
服务提供者(子工程)
pom.xml
<?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">
<parent>
<artifactId>eureka-parent</artifactId>
<groupId>org.example</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>eureka-provider</artifactId>
<dependencies>
<!-- spring boot web -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- eureka-client -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
</dependencies>
</project>
启动类
package com;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
/**
* 启动类
*/
@EnableEurekaClient // 该注解在SpringCloud新版本中可以省略
@SpringBootApplication
public class ProviderApp {
public static void main(String[] args) {
SpringApplication.run(ProviderApp.class, args);
}
}
application.yml
server:
port: 8000
eureka:
instance:
hostname: localhost # 主机名
client:
service-url:
defaultZone: http://localhost:8761/eureka # eureka服务端地址,将来客户端使用该地址和eureka进行通信
spring:
application:
name: eureka-provider # 设置当前应用的名称。这会在eureka中Application显示,且需要使用该名称来获取路径
domain
package com.domain;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Goods {
private int id;
private String name;
private double price;
private int skuNum;
@Override
public String toString() {
return "Goods{" +
"id=" + id +
", name='" + name + '\'' +
", price=" + price +
", skuNum=" + skuNum +
'}';
}
}
controller
package com.controller;
import com.domain.Goods;
import com.service.GoodsService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
@RequestMapping("/goods")
public class GoodsController {
@Autowired
private GoodsService goodsService;
@GetMapping("findOne/{id}")
public Goods findGoods(@PathVariable("id") int id){
return goodsService.findOne(id);
}
}
service
package com.service;
import com.dao.GoodsDao;
import com.domain.Goods;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class GoodsService {
@Autowired
private GoodsDao goodsDao;
public Goods findOne(int id){
return goodsDao.findOne(id);
}
}
dao
package com.dao;
import com.domain.Goods;
import org.springframework.stereotype.Repository;
@Repository
public class GoodsDao {
public static Goods findOne(int id){
Goods phone = new Goods(1, "华为P10", 6999.00, 20);
return phone;
}
}
服务调用者(子工程)
pom.xml
<?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">
<parent>
<artifactId>eureka-parent</artifactId>
<groupId>org.example</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>eureka-consumer</artifactId>
<dependencies>
<!-- spring boot web -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- eureka-client -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
</dependencies>
</project>
启动类
package com;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
@EnableDiscoveryClient // 激活DiscoveryClient
@EnableEurekaClient
@SpringBootApplication
public class ConsumerApp {
public static void main(String[] args) {
SpringApplication.run(ConsumerApp.class, args);
}
}
application.yml
server:
port: 8001
eureka:
instance:
hostname: localhost # 主机名
client:
service-url:
defaultZone: http://localhost:8761/eureka # eureka服务端地址,将来客户端使用该地址和eureka进行通信
spring:
application:
name: eureka-consumer # 设置当前应用的名称。这会在eureka中Application显示,且需要使用该名称来获取路径
RestTemplateConfig
- RestTemplateConfig 是 Spring 提供的一种简单便捷的模板类,用于在 java 代码里访问 restful 服务。
• 其功能与 HttpClient 类似,但是 RestTemplate 实现更优雅,使用更方便。
package com.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;
@Configuration
public class RestTemplateConfig {
@Bean
public RestTemplate restTemplate() {
return new RestTemplate();
}
}
domain
package com.domain;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Goods {
private int id;
private String name;
private double price;
private int skuNum;
@Override
public String toString() {
return "Goods{" +
"id=" + id +
", name='" + name + '\'' +
", price=" + price +
", skuNum=" + skuNum +
'}';
}
}
controller
package com.controller;
import com.domain.Goods;
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.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import java.util.List;
/**
* 服务调用方
*/
@RestController
@RequestMapping("/order")
public class OrderController {
@Autowired
private RestTemplate restTemplate;
@Autowired
private DiscoveryClient discoveryClient;
@GetMapping("/goods/{id}")
public Goods findOrderByGoodsId(@PathVariable("id") int id) {
/*
动态从 Eureka Server 中获取 provider 的 ip 和端口
1. 注入 DiscoveryClient 对象.激活
2. 调用方法
*/
// 演示 discoveryClient 使用
List<ServiceInstance> instances = discoveryClient.getInstances("EUREKA-PROVIDER"); // 服务提供者所配置的实例名称(不区分大小写)
// 判断集合是否有数据
if(instances == null || instances.size() == 0){
// 集合没有数据
return null;
}
ServiceInstance instance = instances.get(0);
String host = instance.getHost(); // 获取ip
int port = instance.getPort(); // 获取端口
/*
远程调用Goods服务中的findOne接口:使用RestTemplate
1. 定义Bean restTemplate
2. 注入Bean
3. 调用方法
*/
String url = String.format("http://%s:%d/goods/findOne/%d", host, port, id);
Goods goods = restTemplate.getForObject(url, Goods.class);
return goods;
}
}
运行效果:
访问 http://localhost:8001/order/goods/1 ,返回:{"id":1,"name":"华为P10","price":6999.0,"skuNum":20}
1.3 Eureka 相关配置及特性
instance 相关属性
-
Eureka Instance 的配置信息全部保存在org.springframework.cloud.netflix.eureka.EurekaInstanceConfigBean 配置类里,实际上它是 com.netflix.appinfo.EurekaInstanceConfig 的实现类,替代了 netflix 的 com.netflix.appinfo.CloudInstanceConfig 的默认实现。
-
Eureka Instance 的配置信息全部以
eureka.instance.xxx
的格式配置。
常用配置:
server 相关属性
-
Eureka Server 注册中心端的配置是对注册中心的特性配置。Eureka Server 的配置全部在 org.springframework.cloud.netflix.eureka.server.EurekaServerConfigBean 里,实际上它是 com.netflix.eureka.EurekaServerConfig 的实现类,替代了 netflix 的默认实现。
-
Eureka Server 的配置全部以
eureka.server.xxx
的格式进行配置。
常用配置:
注意:上述配置一般在生产环境保持默认即可(生产环境配置原则是尽量减少环境变化),在开发或测试则可以为了方便而修改配置。
1.4 Eureka 高可用
搭建示例:
- 搭建两个 Eureka Server
- 分别进行配置:相互注册
- Eureka Client 分别注册到这两个 Eureka Server 中
Eureka Server 搭建
修改本地 host 文件:
eureka-server-1
application.yml:
server:
port: 8761
eureka:
instance:
hostname: eureka-server1 # 主机名
client:
service-url:
defaultZone: http://eureka-server2:8762/eureka
register-with-eureka: true # 是否将自己的路径 注册到eureka上。eureka server 不需要的,eureka provider client 需要
fetch-registry: true # 是否需要从eureka中抓取路径。eureka server 不需要的,eureka consumer client 需要
spring:
application:
name: eureka-server-ha
eureka-server-2
application.yml:
server:
port: 8762
eureka:
instance:
hostname: eureka-server2 # 主机名
client:
service-url:
defaultZone: http://eureka-server1:8761/eureka
register-with-eureka: true # 是否将自己的路径 注册到eureka上。eureka server 不需要的,eureka provider client 需要
fetch-registry: true # 是否需要从eureka中抓取路径。eureka server 不需要的,eureka consumer client 需要
spring:
application:
name: eureka-server-ha
Eureka Client 配置
分别修改服务提供者和服务消费者配置文件中的注册服务地址:
...
eureka:
client:
service-url:
defaultZone: http://eureka-server1:8761/eureka,http://eureka-server2:8762/eureka # eureka 服务端地址
...
干掉其中一台 server,验证 client 仍能正常访问。
2. Consul
2.1 Consul 介绍
Consul 是由 HashiCorp 基于 Go 语言开发的,支持多数据中心、分布式、高可用的服务发布和注册服务软件。
- 用于实现分布式系统的服务发现与配置。
- 使用起来也较为简单,具有天然可移植性(支持 Linux、windows 和 Mac OS);安装包仅包含一个可执行文件,方便部署。
- 官网:https://www.consul.io
启动 consul:
-
启动命令:
-
dev 模式:不会持久化数据
-
控制台:
2.2 入门案例
- 搭建 Provider 和 Consumer 服务。
- 使用 RestTemplate 完成远程调用。
- 将 Provider 服务注册到 Consul 中。
- Consumer 服务 通过从 Consul 中抓取 Provider 地址完成远程调用。
Provider
- pom.xml:
<dependencies>
<!--consul 客户端-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-consul-discovery</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
- application.yml:
server:
port: 8000
spring:
cloud:
consul:
host: localhost # consul 服务端的 ip
port: 8500 # consul 服务端的端口 默认8500
discovery:
service-name: ${spring.application.name} # 当前应用注册到consul的名称
prefer-ip-address: true # 注册ip
application:
name: consul-provider # 应用名称
consumer
- pom.xml:
<dependencies>
<!--consul 客户端-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-consul-discovery</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
- application.yml:
server:
port: 9000
spring:
cloud:
consul:
host: localhost # consul 服务端的 ip
port: 8500 # consul 服务端的端口 默认8500
discovery:
service-name: ${spring.application.name} # 当前应用注册到consul的名称
prefer-ip-address: true # 注册ip
application:
name: consul-consumer # 应用名称
- OrderController:
package com.consul.controller;
import com.consul.domain.Goods;
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.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import java.util.List;
/**
* 服务的调用方
*/
@RestController
@RequestMapping("/order")
public class OrderController {
@Autowired
private RestTemplate restTemplate;
@Autowired
private DiscoveryClient discoveryClient;
@GetMapping("/goods/{id}")
public Goods findGoodsById(@PathVariable("id") int id){
// 演示discoveryClient 使用
List<ServiceInstance> instances = discoveryClient.getInstances("consul-PROVIDER");
// 判断集合是否有数据
if(instances == null || instances.size() == 0){
// 集合没有数据
return null;
}
ServiceInstance instance = instances.get(0);
String host = instance.getHost(); // 获取ip
int port = instance.getPort(); // 获取端口
System.out.println(host);
System.out.println(port);
String url = "http://"+host+":"+port+"/goods/findOne/"+id;
// 3. 调用方法
Goods goods = restTemplate.getForObject(url, Goods.class);
return goods;
}
}
3. Nacos
3.1 Nacos 介绍
Nacos(Dynamic Naming and Configuration Service) 是阿里巴巴 2018 年 7 月开源的项目。
-
它专注于服务发现和配置管理领域,致力于帮你发现、配置和管理微服务。Nacos 支持几乎所有主流类型的“服务”的发现、配置和管理。
-
一句话概括就是 Nacos = SpringCloud 注册中心 + SpringCloud 配置中心。
-
启动:
-
控制台登录:账号/密码均为:nacos
-
Spring cloud Alibaba 组件:
3.2 入门案例
provider
- pom.xml:
<dependencies>
<!-- nacos -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
<version>0.2.2.RELEASE</version>
</dependency>
<dependency>
<groupId>com.alibaba.nacos</groupId>
<artifactId>nacos-client</artifactId>
<version>1.1.0</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
- application.yml:
server:
port: 8000
spring:
cloud:
nacos:
discovery:
server-addr: 127.0.0.1:8848 # 配置nacos 服务端地址
application:
name: nacos-provider # 服务名称
consumer
- pom.xml:
<dependencies>
<!-- nacos -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
<version>0.2.2.RELEASE</version>
</dependency>
<dependency>
<groupId>com.alibaba.nacos</groupId>
<artifactId>nacos-client</artifactId>
<version>1.1.0</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
</dependencies>
- application.yml:
server:
port: 9000
spring:
cloud:
nacos:
discovery:
server-addr: 127.0.0.1:8848 # 配置 nacos 服务端地址
application:
name: nacos-consumer # 服务名称
- 控制台显示:
标签:服务,spring,SpringCloud,boot,springframework,eureka,治理,import,org 来源: https://www.cnblogs.com/juno3550/p/16341024.html