sharding-jdbc读写分离

创建一个二个数据库，ds0和ds1，因为只是的demo，所以并没有配置主从同步，在二个数据库都创建一张people的用户表,创建一个SpringBoot项目，pom.xml文件如下：

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.8.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>sharding-read-write</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>sharding-read-write</name>
<description>Demo project for Spring Boot</description>

<properties>
    <java.version>1.8</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jdbc</artifactId>
    </dependency>
    <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>
        <version>2.1.0</version>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.46</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
        <exclusions>
            <exclusion>
                <groupId>org.junit.vintage</groupId>
                <artifactId>junit-vintage-engine</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.apache.shardingsphere</groupId>
        <artifactId>sharding-jdbc-spring-boot-starter</artifactId>
        <version>4.0.0-RC2</version>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

创建实体类people:

package com.coco.entity;

import java.io.Serializable;

public class People implements Serializable {

private int id;
private String name;

public int getId() {
    return id;
}

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

public String getName() {
    return name;
}

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

创建dao：

package com.coco.dao;

import com.coco.entity.People;
import org.springframework.stereotype.Repository;

import java.util.List;

@Repository
public interface PeopleMapper {

      void addPeople(People people);

      List<People> getData();
}

在resources目录下创建一个mappers的目录放置people.xml的配置文件：

<?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.coco.dao.PeopleMapper">

    <resultMap id="userMap" type="com.coco.entity.People">
        <result column="name" property="name" jdbcType="VARCHAR"/>
        <result column="id" property="id" jdbcType="INTEGER"/>
    </resultMap>

   <insert id="addPeople">
       insert into people (name) value (#{name})
   </insert>

    <select id="getData" resultMap="userMap">
        select * from people
    </select>

</mapper>

启动类：

package com.coco;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan("com.coco.dao")
public class ShardingReadWriteApplication {

    public static void main(String[] args) {
        SpringApplication.run(ShardingReadWriteApplication.class, args);
    }

 }

application.properties:

mybatis.type-aliases-package=com.coco.entity
mybatis.mapper-locations=classpath:mappers/*.xml

spring.shardingsphere.datasource.names=ds0,ds1

spring.shardingsphere.datasource.ds0.type=com.zaxxer.hikari.HikariDataSource
spring.shardingsphere.datasource.ds0.driver-class-name=com.mysql.jdbc.Driver
spring.shardingsphere.datasource.ds0.jdbc-url=jdbc:mysql://localhost:3306/ds0
spring.shardingsphere.datasource.ds0.username=root
spring.shardingsphere.datasource.ds0.password=root

spring.shardingsphere.datasource.ds1.type=com.zaxxer.hikari.HikariDataSource
spring.shardingsphere.datasource.ds1.driver-class-name=com.mysql.jdbc.Driver
spring.shardingsphere.datasource.ds1.jdbc-url=jdbc:mysql://localhost:3306/ds1
spring.shardingsphere.datasource.ds1.username=root
spring.shardingsphere.datasource.ds1.password=root


spring.shardingsphere.masterslave.name=ms
spring.shardingsphere.masterslave.master-data-source-name=ds0
spring.shardingsphere.masterslave.slave-data-source-names=ds1

spring.shardingsphere.props.sql.show=true

编写的测试类：

@RestController
public class PeopleController {


@Autowired
private PeopleMapper peopleMapper;

@RequestMapping("addPeople")
public String addPeople() {
    People people = new People();
    people.setName("coco");
    peopleMapper.addPeople(people);
    return "success";
}

@RequestMapping("getData")
public Object getData() {
    return peopleMapper.getData();
}
}

在插入数据和查询的时候可以看下控制台，shardingsphere的执行sql会打印在控制台上，在插入数据的时候会将数据插入到ds0也就是主数据库中，查询会走从数据库，也就是ds1数据库