项目结构：

首先创建一个Maven父工程：springcloud-example，相关的pom.xml如下：

      
          
       
        4.0.0
           
       
        com.cn
           
       
        springcloud-example
           
       
        1.0-SNAPSHOT
           
       
        pom
           
               
        
         org.springframework.boot
                
        
         spring-boot-starter-parent
                
        
         2.0.3.RELEASE
                
            
           
               
        
         user-service
                
        
         consumer-demo
                
        
         eureka-server
                
        
         zuul-demo
            
           
               
        
         UTF-8
                
        
         UTF-8
                
        
         1.8
                
        
         Finchley.SR2
            
           
               
                    
                         
          
           org.springframework.cloud
                          
          
           spring-cloud-dependencies
                          
          
           ${spring-cloud.version}
                          
          
           pom
                          
          
           import
                      
                     
                         
          
           tk.mybatis
                          
          
           mapper-spring-boot-starter
                          
          
           2.0.4
                      
                     
                         
          
           mysql
                          
          
           mysql-connector-java
                          
          
           5.1.32
                      
                 
            
           
               
                    
         
          org.projectlombok
                     
         
          lombok
                 
            
           
               
                    
                         
          
           org.springframework.boot
                          
          
           spring-boot-maven-plugin
                      
                 
            
       
      

 接着创建服务提供方：user-service，pom.xml如下：

      
          
               
        
         springcloud-example
                
        
         com.cn
                
        
         1.0-SNAPSHOT
            
           
       
        4.0.0
           
       
        user-service
           
               
                    
         
          org.springframework.boot
                     
         
          spring-boot-starter-web
                 
                
                    
         
          mysql
                     
         
          mysql-connector-java
                 
                
                    
         
          tk.mybatis
                     
         
          mapper-spring-boot-starter
                 
                
                
                    
         
          org.springframework.cloud
                     
         
          spring-cloud-starter-netflix-eureka-client
                 
            
       
      

对应的启动方法UserApplication

package com.cn;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.cloud.client.discovery.EnableDiscoveryClient;/** * Created by 13632 on 2018-12-11. */@SpringBootApplication@tk.mybatis.spring.annotation.MapperScan("com.cn.mapper")//启动Eureka注册中心@EnableDiscoveryClientpublic class UserApplication {    public static void main(String[] args) {        SpringApplication.run(UserApplication.class, args);    }}

pojo类

通用mapper需要加上@Table、@Id、@KeySql等注解

package com.cn.pojo;import lombok.Data;import tk.mybatis.mapper.annotation.KeySql;import javax.persistence.Id;import javax.persistence.Table;import java.util.Date;/** * Created by 13632 on 2018-12-11. *///因为引入了lombok插件，所有只要使用@Data注解就能自动实现get、set、toString等方法@Data//连接数据库的user表@Table(name = "user")public class User {    //主键自增    @Id    @KeySql(useGeneratedKeys = true)    private Integer id;    private String username;    private String password;    private Date birth;    private String gender;    private String email;    private Integer status;    private Date regtime;}

mapper类

package com.cn.mapper;import com.cn.pojo.User;import tk.mybatis.mapper.common.Mapper;/** * Created by 13632 on 2018-12-11. *///继承tk.mybatis的Mapper类就可以不用在写相关的mapper方法public interface UserMapper extends Mapper
      
        {}
      

service

package com.cn.service;import com.cn.mapper.UserMapper;import com.cn.pojo.User;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;/** * Created by 13632 on 2018-12-11. */@Servicepublic class UserService {    @Autowired    private UserMapper userMapper;    public User queryById(Integer id) {        return userMapper.selectByPrimaryKey(id);    }}

web

package com.cn.web;import com.cn.pojo.User;import com.cn.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.RequestMapping;import org.springframework.web.bind.annotation.RestController;/** * Created by 13632 on 2018-12-11. */@RestController@RequestMapping("/user")public class UserController {    @Autowired    private UserService userService;    @GetMapping("/{id}")    public User queryById(@PathVariable("id") Integer id) {        //这个代码测试用，让它休眠2秒，实现服务熔断，可以删掉//        try {//            Thread.sleep(2000L);//        } catch (InterruptedException e) {//            e.printStackTrace();//        }        return userService.queryById(id);    }}

application.yml文件

server:  port: 8180spring:  datasource:    url: jdbc:mysql://localhost:3306/ssm_blog    username: root    password: 85586537  application:    name: user-servicemybatis:  type-aliases-package: com.cn.pojo#注册到eurekaeureka:  client:    service-url:    #高可用     defaultZone: http://server1:10086/eureka,http://server2:10087/eureka    #服务提供方需要配置下面这些，默认采用官方的值就可以，下面这些数字就是默认#  instance:  #每隔30秒向Eureka发一次心跳，那么服务还活着    #lease-renewal-interval-in-seconds: 30  #如果超过90s没有发心跳的话，表示Eureka挂了，那么Eureka的状态会显示成DOWN    #lease-expiration-duration-in-seconds: 90

    服务的调用方（消费方）：consumer-demo

相关的pom.xml文件

      
          
               
        
         springcloud-example
                
        
         com.cn
                
        
         1.0-SNAPSHOT
            
           
       
        4.0.0
           
       
        consumer-demo
           
               
                    
         
          org.springframework.boot
                     
         
          spring-boot-starter-web
                 
                
                    
         
          org.springframework.cloud
                     
         
          spring-cloud-starter-netflix-eureka-client
                 
                
                
                    
                    
                
                
                
                    
         
          org.springframework.cloud
                     
         
          spring-cloud-starter-netflix-hystrix
                 
                
                
                    
         
          org.springframework.cloud
                     
         
          spring-cloud-starter-openfeign
                 
            
       
      

启动类：ConsumerApplication

package com.cn;import org.springframework.boot.SpringApplication;import org.springframework.cloud.client.SpringCloudApplication;import org.springframework.cloud.openfeign.EnableFeignClients;/** * Created by 13632 on 2018-12-11. *//*SpringCloudApplication包含了@SpringBootApplication、@EnableDiscoveryClient、@EnableCircuitBreaker */@SpringCloudApplication@EnableFeignClients  //开启Feignpublic class ConsumerApplication {    //有了feign，负载均衡可以省略了，因为默认加了负载均衡//    @Bean//    //负载均衡//    @LoadBalanced//    public RestTemplate restTemplate() {//        return new RestTemplate();//    }    public static void main(String[] args) {        SpringApplication.run(ConsumerApplication.class, args);    }}

pojo类

package com.cn.pojo;import lombok.Data;import java.util.Date;/** * Created by 13632 on 2018-12-11. * 调用方直接调用提供方就可以，所以数据库那些不需要了 */@Datapublic class User {    private Integer id;    private String username;    private String password;    private Date birth;    private String gender;    private String email;    private Integer status;    private Date regtime;}

web层，因为使用了Feign远程调用，实现接口进行调用，使代码看起来专业点。

package com.cn.web;import com.cn.client.UserClient;import com.cn.pojo.User;import org.springframework.beans.factory.annotation.Autowired;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;/** * Created by 13632 on 2018-12-11. */@RestController@RequestMapping("/consumer")public class ConsumerController {    @Autowired    private UserClient userClient;    @Autowired    private DiscoveryClient discoveryClient;    //feign案例    @GetMapping("/{id}")    public User queryById(@PathVariable("id") Integer id) {        //因为引入了ribbon负载均衡，因此只需要http://服务的id/即可。        return userClient.queryById(id);    }}

接口

package com.cn.client;import com.cn.pojo.User;import org.springframework.cloud.openfeign.FeignClient;import org.springframework.web.bind.annotation.GetMapping;import org.springframework.web.bind.annotation.PathVariable;/** * Created by 13632 on 2018-12-17. * Feign远程服务调用接口 * 需要请求方法、请求路径、请求参数、返回参数这4个值 * 如果要实现服务熔断的话，需要在@FeignClient加上实现方法类 *///获取服务列表@FeignClient(value = "user-service",fallback = UserClientFallBack.class)public interface UserClient {    @GetMapping("user/{id}")    User queryById(@PathVariable("id") Integer id);}

接口实现类

package com.cn.client;import com.cn.pojo.User;import org.springframework.stereotype.Component;/** * Created by 13632 on 2018-12-17. * feign的熔断需要自己配置，实现对应的接口，然后写上熔断逻辑方法 *///交给spring管理@Componentpublic class UserClientFallBack implements UserClient {    @Override    public User queryById(Integer id) {        User user = new User();        user.setUsername("未知用户");        return user;    }}

application.yml配置

server:  port: 8280spring:  application:    name: consumer-service#注册到eurekaeureka:  client:    service-url:     defaultZone: http://server1:10086/eureka,http://server2:10087/eureka      #服务消费方，fetch-registry是否要拉取服务列表，默认为true， 下面的这个配置是每隔X秒拉取一次。    #fetch-registry: true    #registry-fetch-interval-seconds: 30#feign开启熔断feign:  hystrix:    enabled: true#feign的负载均衡，ribbon的超时时长默认的话(read+connect)*2小于hystrix的超时时长ribbon:  ConnectionTimeout: 500  ReadTimeout: 2000#针对全局超时连接配置，可以直接采用默认1秒，hystrix:  command:    default:      execution:        isolation:          thread:            timeoutInMilliseconds: 3000

    注册中心：Eureka-server

Pom.xml文件

      
          
               
        
         springcloud-example
                
        
         com.cn
                
        
         1.0-SNAPSHOT
            
           
       
        4.0.0
           
       
        eureka-server
           
               
                    
         
          org.springframework.cloud
                     
         
          spring-cloud-starter-netflix-eureka-server
                 
            
       
      

启动类EurekaServerApplication

package com.cn;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;/** * Created by 13632 on 2018-12-12. */@SpringBootApplication@EnableEurekaServerpublic class EurekaServerApplication {    public static void main(String[] args) {        SpringApplication.run(EurekaServerApplication.class, args);    }}

  application.yml配置具体参考前一篇高可用配置

   网关：zuul-demo

pom.xml文件

      
          
               
        
         springcloud-example
                
        
         com.cn
                
        
         1.0-SNAPSHOT
            
           
       
        4.0.0
           
       
        zuul-demo
           
               
                
                    
         
          org.springframework.cloud
                     
         
          spring-cloud-starter-netflix-zuul
                 
                
                    
         
          org.springframework.cloud
                     
         
          spring-cloud-starter-netflix-eureka-client
                 
                
                
                    
         
          org.apache.commons
                     
         
          commons-lang3
                 
            
       
      

启动类：ZuulApplication

package com.cn;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.cloud.netflix.zuul.EnableZuulProxy;/** * Created by 13632 on 2018-12-17. */@SpringBootApplication@EnableZuulProxypublic class ZuulApplication {    public static void main(String[] args) {        SpringApplication.run(ZuulApplication.class, args);    }}

Zuul的作用就是进行拦截，判断是否有权限

package com.cn.filter;import com.netflix.zuul.ZuulFilter;import com.netflix.zuul.context.RequestContext;import com.netflix.zuul.exception.ZuulException;import org.apache.commons.lang3.StringUtils;import org.springframework.cloud.netflix.zuul.filters.support.FilterConstants;import org.springframework.http.HttpStatus;import org.springframework.stereotype.Component;import javax.servlet.http.HttpServletRequest;/** * Created by 13632 on 2018-12-18. * 判断用户是否有access-token，如果没有就拦截，有就放行 */@Componentpublic class LoginFilter extends ZuulFilter {    /*    拦截器类型：包括pre、route、post、error    pre：请求之前进行拦截，常用这个    route：请求到达后拦截    error：抛出异常拦截    post：在route和error之后执行     */    @Override    public String filterType() {        return FilterConstants.PRE_TYPE;    }    //请求顺序，数据越小优先级越高    @Override    public int filterOrder() {        return FilterConstants.PRE_DECORATION_FILTER_ORDER - 1;    }    //是否拦截    @Override    public boolean shouldFilter() {        return true;    }    //    @Override    public Object run() throws ZuulException {        //这步的话直接打开ZuulFilter的继承关系中的FormBodyWrapperFilter的run方法即可看到        //获取请求上下文        RequestContext ctx = RequestContext.getCurrentContext();        //获取request        HttpServletRequest request = ctx.getRequest();        //获取请求参数access-token        String token = request.getParameter("access-token");        //判断是否存在        if (StringUtils.isBlank(token)) {            /*            不存在，未登录，进行拦截            因为是用zuul实现的，所以需要下面这个方法            然后返回一个状态码：403 FORBIDDEN 表示禁用             */            ctx.setSendZuulResponse(false);            ctx.setResponseStatusCode(HttpStatus.FORBIDDEN.value());        }        return null;    }}

application.yml

server:  port: 10010#zuul需要到eureka拉取服务列表，此外，它默认实现了负载均衡，所有需要进行配置eureka:  client:    service-url:     defaultZone: http://server1:10086/eureka,http://server2:10087/eurekaspring:  application:    name: zuul-serviceribbon:  ConnectionTimeout: 500  ReadTimeout: 1000hystrix:  command:    default:      execution:        isolation:          thread:            timeoutInMilliseconds: 4000#下面这个配置是可以设置不能某个服务不能用网关访问，是一个集合，注意配置格式#zuul:#  ignored-services:#    - consumer-service#    - user-service#下面这个配置可以直接忽略，因为默认的话直接访问http://ip+端口/服务Id/路径，比如可以直接访问#localhost:10010/user-service/user/2等#zuul:#  routes:#    user-service: /user-service/**