认识并学会springCloud的使用

SpringCloud将现在一些流行的技术整合到一起，实现如：配置管理，服务发现，智能路由，负载均衡，熔断器，控制总线，集群状态等等功能。主要涉及的组件有

netflix

• Eureka：注册中心

• Zuul：服务网关

• Ribbon：负载均衡

• Feign：服务调用

• Hystix：熔断器

环境准备：一个数据库和表tb_user

1.创建一个父工程，和子模块consumer-demo，eureka-server，eureka-server2（两个是eureka的高可用性练习），user-server，(user-server2是对user server的集群练习可以不要)zuul-Demo。

（完整代码：https://gitee.com/mountaincold/cloudDemo）

2. 创建注册中心 eureka-server

　　1.pom.xml 导入依赖 eureka服务端

　　2. 创建启动类 eureka1

　　3. 设置application.yml

eureka-server2相同把端口换成10087，注册地址换成10086就行了

2.创建服务提供者userservice

　　1. pom.xml的配置 导入依赖

 <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
        </dependency>
        <!-- Eureka客户端 -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
    </dependencies>

　　2. 设置application.yml配置文件

server:
  port: 8081
spring:
  datasource:
    url: jdbc:mysql://localhost:3306/mybatis
    username: root
    password: 960326
  application:
    name: userservice
logging:
  level:
    com.practice:
      debug
eureka:
  client:
    service-url: #eurekaServer 地址
      defaultZone: http://127.0.0.1:10086/eureka,http://127.0.0.1:10087/eureka
  instance:
    prefer-ip-address: true #当调用getHostname获取实例的hostname时 返回ip而不是host名称
    ip-address: 127.0.0.1 #指定自己的ip信息 不指定的话会自己寻找
    lease-expiration-duration-in-seconds: 10 #服务失效时间 默认90秒
    lease-renewal-interval-in-seconds: 5 #服务续约时间的间隔，默认30秒
    instance-id: ${spring.application.name}:${server.port} #设置id

　　2.创建启动类，和pojo对象类

@Table(name = "tb_user")
public class User implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    // 用户名
    private String userName;

    // 密码
    private String password;

    // 姓名
    private String name;

    // 年龄
    private Integer age;

    // 性别，1男性，2女性
    private Integer sex;

    // 出生日期
    private Date birthday;

    // 创建时间
    private Date created;

    // 更新时间
    private Date updated;

    // 备注
//    private String note;

    // 。。。省略getters和setters
    //TODO 需要手动添加getter，setter
}

　　

　　3.创建controller，service ，mapper

package com.practice.controller;

import com.practice.pojo.User;
import com.practice.service.UserService;
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.RestController;
import org.springframework.web.bind.annotation.RequestMapping;

@RestController
@RequestMapping("user")
public class UserController {

    @Autowired
    private UserService userService;

    @GetMapping("/{id}")
    public User queryById(@PathVariable("id") Long id) {
        return this.userService.queryById(id);
    }
}

/**
*设置睡眠是为了测试熔断器
*/
package com.practice.service;

import com.practice.mapper.UserMapper;
import com.practice.pojo.User;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class UserService {

    @Autowired
    private UserMapper userMapper;
    private static final Logger logger = LoggerFactory.getLogger(UserService.class);
    public User queryById(Long id) {
        Long startTime = System.currentTimeMillis();
        int time = (int)(Math.random()*2000+1);
        try {
            Thread.sleep(time);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        User user = this.userMapper.selectByPrimaryKey(id);
        Long endTime = System.currentTimeMillis();
        logger.info("本次查询：{},花费时间为{}ms",id,endTime-startTime);
        return user;
    }
}

/**
*通用mapper的使用，可以动态生成实现子类和查询语言适用于单表查询
*/

package com.practice.mapper;

import com.practice.pojo.User;
import tk.mybatis.mapper.common.Mapper;

public interface UserMapper extends Mapper<User> {
}

3创建服务消费者cosumer-demo

　　1.pom.xml配置 需要的依赖

 <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- 添加OkHttp支持 -->
        <dependency>
            <groupId>com.squareup.okhttp3</groupId>
            <artifactId>okhttp</artifactId>
            <version>3.9.</version>
        </dependency>
        <!-- Eureka客户端 -->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <!--测试-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
        <!--Hystrix依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
        </dependency>
        <!--Feign的依赖-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
    </dependencies>

　　2. application.xml的配置

Spring:
  application:
    name: consumer
eureka:
  client:
    service-url: #eurekaServer地址
      defaultZone: http://127.0.0.1:10086/eureka,http://127.0.0.1:10087/eureka
    registry-fetch-interval-seconds: 5 #获取更新服务列表 默认时间为30秒

  instance:
    prefer-ip-address: true #当其它服务获取地址时提供ip而不是hostname
    ip-address: 127.0.0.1 #指定自己的ip信息 不指定的话会自己寻找
ribbon: #修改服务负载均衡的分流规则
  NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule #随机 默认为轮询
  ConnectTimeout: 250 # ribbon 连接超时时间
  ReadTimeout: 1000 #Ribbon 数据读取超时时间
feign:
  hystrix:
    enabled: true #开启feign的熔断支持默认关闭
  compression:
    request:
      enabled: true # 开启请求压缩
      mime-types: text/html,application/xml,application/json # 设置压缩的数据类型
      min-request-size: 2048 # 设置触发压缩的大小下限
logging:
  level:
    com.consumer:
      debug

　　3. 创建启动类 和pojo对象类

package com;

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

@EnableDiscoveryClient
@SpringBootApplication
//@EnableHystrix
@EnableFeignClients
public class Consumer {
//    @Bean
//    @LoadBalanced //开启负载均衡
//    public RestTemplate restTemplate(){
//    // 使用OKHTTP客户端，只需注入工厂
//       return new RestTemplate(new OkHttp3ClientHttpRequestFactory());
//    }
// 因为Feign 中自动集成 Ribbon 负载均衡 所以不需要自定义RestTemplate
    public static void main(String[] args) {
        SpringApplication.run(Consumer.class);

    }
}
/**
*属性类型和user-service中相同但是不用加@table之类的注解
*/
public class User  {

    private static final long serialVersionUID = 1L;

    private Long id;

    // 用户名
    private String userName;

    // 密码
    private String password;

    // 姓名
    private String name;

    // 年龄
    private Integer age;

    // 性别，1男性，2女性
    private Integer sex;

    // 出生日期
    private Date birthday;

    // 创建时间
    private Date created;

    // 更新时间
    private Date updated;

    //TODO 需要手动添加getter，setter
}

　　4. 创建 controller，service，config （dao是测试hystrix时创建的，feign中支持熔断所以不用创建）

package com.consumer.controller;

import com.consumer.pojo.User;
import com.consumer.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
@RequestMapping("consume")
public class ConsumerController {
    @Autowired
    private UserService userService;

    @GetMapping
    public List<User> consume(@RequestParam("ids")List<Long> ids){
    return this.userService.queryUserByIds(ids);
    }
}

package com.consumer.service;

import com.consumer.config.UserFeignClient;
import com.consumer.config.impl.UserFeignClientImpl;
import com.consumer.dao.UserDao;
import com.consumer.pojo.User;
//import com.netflix.discovery.DiscoveryClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

import java.util.ArrayList;
import java.util.List;

@Service
public class UserService {

  /**
   * 根据服务名称，获取服务实例
   * */

     @Autowired
     private UserFeignClient userFeignClient;
    public List<User> queryUserByIds(List<Long> ids) {
        List<User> users = new ArrayList<>();

        ids.forEach(id ->{
            users.add(userFeignClient.queryById(id));
           /* try {
                Thread.sleep(500);
线程睡眠用于测试可以删除
            } catch (InterruptedException e) {
                e.printStackTrace();
            }*/
        });
        return users;
    }

}

package com.consumer.config;

import com.consumer.config.impl.FeignConfig;
import com.consumer.config.impl.UserFeignClientImpl;
import com.consumer.pojo.User;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;

@FeignClient(value = "userservice",fallback = UserFeignClientImpl.class,configuration = FeignConfig.class)

public interface UserFeignClient {
    @GetMapping("/user/{id}")
    public User queryById(@PathVariable("id") Long id);
}

package com.consumer.config.impl;

import com.consumer.config.UserFeignClient;
import com.consumer.pojo.User;
import org.springframework.stereotype.Component;

@Component
public class UserFeignClientImpl implements UserFeignClient {

    @Override
    public User queryById(Long id) {
        User user = new User();
        user.setId(id);
        user.setName("请求超时，请稍后重试--feign");
        return user;
    }
}

package com.consumer.config.impl;

import feign.Logger;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * 编写配置类定义feign的日志级别 feign支持四种级别
 * - NONE：不记录任何日志信息，这是默认值。
 * - BASIC：仅记录请求的方法，URL以及响应状态码和执行时间
 * - HEADERS：在BASIC的基础上，额外记录了请求和响应的头信息
 * - FULL：记录所有请求和响应的明细，包括头信息、请求体、元数据
 */
@Configuration
public class FeignConfig {
    @Bean
    Logger.Level feignLoggerLevel() {
        return Logger.Level.FULL;
    }
}

4. 创建zuul网关

1.pom.xml中的依赖

 <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-zuul</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
    </dependencies>

　　2. application.yml

server:
  port: 10010
spring:
  application:
    name: gateway
zuul:
  routes:
    userservice: userservice/**  #简便方式
  prefix: /api #添加路由前缀
 #     path: /userservice/** #这是映射路径
#    serviceId: userservice #指定服务名称
#      url: http://127.0.0.1:8081 映射路径对应的实际url地址
eureka:
  client:
    registry-fetch-interval-seconds: 5 #循环获取服务列表
    service-url:
      defaultZone: http://127.0.0.1:10086/eureka
  instance:
    prefer-ip-address: true
    ip-address: 127:0.0.1

　　3. 创建启动器

package com.zuul;

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

@SpringBootApplication
@EnableDiscoveryClient
@EnableZuulProxy //开启网关功能
public class Zuul {
    public static void main(String[] args) {
        SpringApplication.run(Zuul.class);
    }
}

　　测试成功的页面：