java springcloud版b2b2c社交电商spring cloud分布式微服务-docker-feign(四)

简介

Spring Cloud大型企业分布式微服务云构建的B2B2C电子商务平台源码请加企鹅求求：一零三八七七四六二六。上一节，我们讨论了怎么通过，restTemlate调用cloud的生产者，实现起来还是比较复杂的，尤其是在消费复杂的Restful服务的时候，还需要进行一系列的转换，编解码等，使用Feign就完全不用考虑这个问题.。

一、feinn介绍

Feign是一种声明式、模板化的HTTP客户端。在Spring Cloud中使用Feign, 我们可以做到使用HTTP请求远程服务时能与调用本地方法一样的编码体验，开发者完全感知不到这是远程方法，更感知不到这是个HTTP请求，这整个调用过程和Dubbo的RPC非常类似。开发起来非常的优雅。

二、创建模块（microservice-consumer-movie-feign）

项目结构如下：

三、pom.xml

   
       microservice-spring-cloud
       com.jacky
       1.0-SNAPSHOT
   
   4.0.0

   microservice-consumer-movie-feign
   jar

   
       UTF-8
       UTF-8
       1.8
   

   
       
           org.springframework.boot
           spring-boot-starter-web
       

       
           org.springframework.cloud
           spring-cloud-starter-eureka
       

       
           org.springframework.boot
           spring-boot-starter-actuator
       

       
           org.springframework.cloud
           spring-cloud-starter-feign
       

       
   
   
       
           
               com.spotify
               docker-maven-plugin
               
                   
                   
                       build-image
                       install
                       
                           build
                       
                   
               
               
                   
                   http://192.168.6.130:5678
                   true
                   
                   ${docker.repostory}/${docker.image.prefix}/${project.artifactId}:${project.version}
                   
                   java:openjdk-8-jdk-alpine
                   
                   ["java", "-jar", "/${project.build.finalName}.jar"]
                   
                       
                           /
                           ${project.build.directory}
                           ${project.build.finalName}.jar
                       
                   
               
           
       
   

四、配置文件application.yml

spring:
  application:
    name: microservice-consumer-movie-feign
server:
  port: 7901
eureka:
  client:
    healthcheck:
      enabled: true
    serviceUrl:
      defaultZone: http://jacky:admin@peer1:8761/eureka/,http://jacky:admin@peer2:8762/eureka/,http://jacky:admin@peer3:8763/eureka/
  instance:
    prefer-ip-address: true
    instance-id: ${spring.application.name}:${spring.cloud.client.ipAddress}:${spring.application.instance_id:${server.port}}

五、MovieController.java

package com.jacky.cloud.controller;

import com.jacky.cloud.entity.User;
import com.jacky.cloud.feign.UserFeignClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
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.client.RestTemplate;

/**
 * Created by jacky on 2017/7/14.
 */
@RestController
public class MovieController {

    @Autowired
    private UserFeignClient userFeignClient;

    @GetMapping("/movie/{id}")
    public User findById(@PathVariable Long id) {
        return this.userFeignClient.findById(id);
    }

    @GetMapping("/test")
    public User testPost(User user) {
        return this.userFeignClient.postUser(user);
    }

    @GetMapping("/test-get")
    public User testGet(User user) {
        return this.userFeignClient.getUser(user);
    }
}

六、实体类User.java

package com.jacky.cloud.entity;

import java.math.BigDecimal;

public class User {
  private Long id;

  private String username;

  private String name;

  private Short age;

  private BigDecimal balance;

  public Long getId() {
    return this.id;
  }

  public void setId(Long id) {
    this.id = id;
  }

  public String getUsername() {
    return this.username;
  }

  public void setUsername(String username) {
    this.username = username;
  }

  public String getName() {
    return this.name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public Short getAge() {
    return this.age;
  }

  public void setAge(Short age) {
    this.age = age;
  }

  public BigDecimal getBalance() {
    return this.balance;
  }

  public void setBalance(BigDecimal balance) {
    this.balance = balance;
  }

}

七、UserFeignClient.java

package com.jacky.cloud.feign;

import com.jacky.cloud.entity.User;
import org.springframework.cloud.netflix.feign.FeignClient;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

/**
 * Created by jacky on 2017/7/14.
 */
@FeignClient("microservice-provider-user")
public interface UserFeignClient {
    /**
     * 根据Id获得User
     * 两个坑：1. @GetMapping不支持   2. @PathVariable得设置value
     * @param id
     * @return
     */
    @RequestMapping(value = "/simple/{id}", method = RequestMethod.GET)
    public User findById(@PathVariable("id") Long id);

    @RequestMapping(value = "/user", method = RequestMethod.POST)
    public User postUser(@RequestBody User user);

    // 该请求不会成功，只要参数是复杂对象，即使指定了是GET方法，feign依然会以POST方法进行发送请求。可能是我没找到相应的注解或使用方法错误。
    // 也就是说复杂对象，feign一定要post的请求方式
    @RequestMapping(value = "/get-user", method = RequestMethod.GET)
    public User getUser(User user);
}

八、启动类(MicroserviceSimpleConsumerMovieApplication.java)

package com.jacky.cloud;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.feign.EnableFeignClients;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
@EnableEurekaClient
@EnableFeignClients
public class MicroserviceSimpleConsumerMovieApplication {
  public static void main(String[] args) {
    SpringApplication.run(MicroserviceSimpleConsumerMovieApplication.class, args);
  }
}

需要JAVASpring Cloud大型企业分布式微服务云构建的B2B2C电子商务平台源码请加企鹅求求：一零三八七七四六二六

标签：springcloud,spring cloud,springcloud微服务,b2b2c,o2o电子商务,java多用户商城系统