HTTP请求 RestFul远程调用

使用RestFul实现远程调用整体上来看要比zookeeper+dubbo实现要容易 , 封装性要更好

提供者如下

首先我们引入依赖

<?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>springcloud</artifactId>
        <groupId>com.starcpdk</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>springcloud-provider-dept-8001</artifactId>

    <dependencies>
        <!--我们需要拿到实体类 , 所以我们需要配置api module-->
        <dependency>
            <groupId>com.starcpdk</groupId>
            <artifactId>springcloud-api</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>

        <!--Junit-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
        </dependency>

        <!--mysql-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <!--数据源-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
        </dependency>

        <!--门面-->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-core</artifactId>
        </dependency>

        <!--mybatis 和springboot的整合包-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>

        <!--test-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-test</artifactId>
        </dependency>

        <!--jetty-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jetty</artifactId>
        </dependency>

        <!--热部署工具-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
    </dependencies>

</project>

然后我们来编写springboot的配置文件

server:
  port: 8001

# mybatis配置
mybatis:
  type-aliases-package: com.starcpdk.springcloud.pojo
  config-location: classpath:mybatis/mybatis-config.xml
  mapper-locations: classpath:mybatis/mapper/*.xml

# spring 的配置
spring:
  application:
    name: springcloud-provider-dept
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource  # 数据源
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/db01?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC
    username: root
    password: root

由于要和数据库交互 , 我们配置以下数据库的相关配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <!--开启二级缓存-->
    <settings>
        <setting name="cacheEnabled" value="true"/>
    </settings>
</configuration>

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.starcpdk.springcloud.mapper.DeptMapper">
    
    <insert id="addDept" parameterType="Dept">
        insert into dept (dname, db_source)
        values (#{dname} , DATABASE());
    </insert>

    <select id="queryDeptById" resultType="Dept" parameterType="Long">
        select *
        from dept where deptno = #{deptno};
    </select>

    <select id="queryAllDept" resultType="Dept">
        select *
        from dept;
    </select>

</mapper>

让我们看看controller

package com.starcpdk.springcloud.controller;

import com.starcpdk.springcloud.pojo.Dept;
import com.starcpdk.springcloud.service.DeptService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

// 提供Restful服务
@RestController
public class DeptController {
    
    
    @Autowired
    DeptService deptService;

    @PostMapping("/dept/add")
    public boolean addDept(@RequestBody Dept dept){
    
    
        return deptService.addDept(dept);
    }

    @GetMapping("/dept/get/{id}")
    public Dept addDept(@PathVariable("id") Long id){
    
    
        return deptService.queryDeptById(id);
    }

    @GetMapping("/dept/queryAll")
    public List<Dept> addDept(){
    
    
        return deptService.queryAllDept();
    }

}

service层和mapper层都是和之前基本一样的

接下来就让我们写调用者吧

<?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>springcloud</artifactId>
        <groupId>com.starcpdk</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>springcloud-consumer-dept-80</artifactId>

    <!--实体类 + Web-->
    <dependencies>
        <dependency>
            <groupId>com.starcpdk</groupId>
            <artifactId>springcloud-api</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
    </dependencies>

</project>

调用者由于是调用远程的 , 因此不需要写service和mapper层
我们只要写controller就可以了 , 让我们看看controller

package com.starcpdk.springcloud.controller;

import com.starcpdk.springcloud.pojo.Dept;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
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.RestController;
import org.springframework.web.client.RestTemplate;

import java.util.List;

@RestController
public class DeptConsumerController {
    
    
    // 理解: 消费者不应该有service
    // RestFul风格
    // url , 实体map  , class<T>resposeType

    @Autowired
    private RestTemplate restTemplate; // 提供多种便捷访问远程http服务的方法 , 简单的restFul服务模板

    private static final String REST_URL_PREFIX = "http://localhost:8001";

    @RequestMapping("/consumer/dept/get/{id}")
    public Dept get(@PathVariable("id") Long id){
    
    
        return restTemplate.getForObject(REST_URL_PREFIX+"/dept/get/" + id , Dept.class);
    }

    @RequestMapping("/consumer/dept/add")
    public boolean add(@RequestBody Dept dept){
    
    
        return restTemplate.postForObject(REST_URL_PREFIX+"/dept/add/" , dept , Boolean.class);
    }

    @RequestMapping("/consumer/dept/list")
    public List<Dept> list(){
    
    
        return restTemplate.getForObject(REST_URL_PREFIX+"/dept/queryAll" , List.class);
    }
}

由于我们需要注入private RestTemplate restTemplate;

所以我们需要让RestTemplate实例放入spring托管
因此我们来看一下config吧

package com.starcpdk.springcloud.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;

@Configuration // 相当于applicationContext.xml
public class ConfigBean {
    
    
    @Bean
    public RestTemplate getRestTemplete(){
    
    
        return new RestTemplate();
    }
}