基于SpringBoot+Druid实现多数据源：原生注解式

前言

本博客姊妹篇

• 基于SpringBoot+Druid实现多数据源：原生注解式
• 基于SpringBoot+Druid实现多数据源：注解+编程式
• 基于SpringBoot+Druid实现多数据源：baomidou多数据源

一、功能描述

• 配置方式：配置文件中实现多数据源，非动态
• 使用方式：使用注解切换数据源

二、代码实现

2.1 配置

# spring配置
spring:
  # 数据源配置
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    druid:
      web-stat-filter:
        enabled: true
        url-pattern: /*
        exclusions: '*.js,*.css,*.gif,*.png,*.jpg,*.ico,/druid/*'
      stat-view-servlet:
        enabled: true
        url-pattern: /druid/*
        login-username: admin
        login-password: 123456
      filter:
        stat:
          enabled: true
          log-slow-sql: true
          slow-sql-millis: 1000
          merge-sql: true
        wall:
          enabled: true
          config:
            multi-statement-allow: true
      master:
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://127.0.0.1:3306/boot_business?useUnicode=true&characterEncoding=UTF8&serverTimezone=GMT%2B8&useSSL=false
        username: root
        password: root
        initial-size: 10
        min-idle: 10
        max-active: 100
        max-wait: 60000
        time-between-eviction-runs-millis: 60000
        min-evictable-idle-time-millis: 300000
        validation-query: select 1
        test-while-idle: true
        test-on-borrow: false
        test-on-return: false
        pool-prepared-statements: true
        max-pool-prepared-statement-per-connection-size: 20
      slave:
        enabled: true
        driver-class-name: com.mysql.cj.jdbc.Driver
        url: jdbc:mysql://127.0.0.1:3306/boot_codegen?useUnicode=true&characterEncoding=UTF8&serverTimezone=GMT%2B8&useSSL=false
        username: root
        password: root
        initial-size: 10
        min-idle: 10
        max-active: 100
        max-wait: 60000
        time-between-eviction-runs-millis: 60000
        min-evictable-idle-time-millis: 300000
        validation-query: select 1
        test-while-idle: true
        test-on-borrow: false
        test-on-return: false
        pool-prepared-statements: true
        max-pool-prepared-statement-per-connection-size: 20

2.2 配置类

package com.qiangesoft.datasource.core;

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceBuilder;
import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import java.util.HashMap;
import java.util.Map;

/**
 * 多数据源配置
 *
 * @author qiangesoft
 * @date 2024-03-14
 */
@Slf4j
@Configuration
public class DataSourceConfiguration {

    @Bean
    @ConfigurationProperties("spring.datasource.druid.master")
    public DruidDataSource masterDataSource() {
        DruidDataSource masterDataSource = DruidDataSourceBuilder.create().build();
        masterDataSource.setName(DataSourceType.MASTER.getType());
        return masterDataSource;
    }

    @Bean
    @ConfigurationProperties("spring.datasource.druid.slave")
    @ConditionalOnProperty(prefix = "spring.datasource.druid.slave", name = "enabled", havingValue = "true")
    public DruidDataSource slaveDataSource() {
        DruidDataSource slaveDataSource = DruidDataSourceBuilder.create().build();
        slaveDataSource.setName(DataSourceType.SLAVE.getType());
        return slaveDataSource;
    }

    @Bean
    @Primary
    public DynamicDataSource dynamicDataSource(DruidDataSource masterDataSource, DruidDataSource slaveDataSource) {
        Map<Object, Object> targetDataSources = new HashMap<>();
        targetDataSources.put(masterDataSource.getName(), masterDataSource);
        targetDataSources.put(slaveDataSource.getName(), slaveDataSource);
        return new DynamicDataSource(masterDataSource, targetDataSources);
    }
}

2.3 多数据源扩展实现

package com.qiangesoft.datasource.core;

import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;

import javax.sql.DataSource;
import java.util.Map;

/**
 * 动态数据源
 *
 * @author qiangesoft
 * @date 2024-03-14
 */
public class DynamicDataSource extends AbstractRoutingDataSource {

    public DynamicDataSource(DataSource defaultTargetDataSource, Map<Object, Object> targetDataSources) {
        super.setDefaultTargetDataSource(defaultTargetDataSource);
        super.setTargetDataSources(targetDataSources);
        super.afterPropertiesSet();
    }

    @Override
    protected Object determineCurrentLookupKey() {
        return DataSourceContext.getDataSource();
    }
}

2.4 切面

package com.qiangesoft.datasource.core;

import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;

import java.util.Objects;

/**
 * 多数据源处理
 *
 * @author qiangesoft
 * @date 2024-03-14
 */
@Slf4j
@Order(1)
@Aspect
@Component
public class DataSourceAspect {

    /**
     * 切点
     */
    @Pointcut("@annotation(com.qiangesoft.datasource.core.DataSource)")
    public void pointCut() {
    }

    /**
     * 通知
     *
     * @param joinPoint
     * @return
     * @throws Throwable
     */
    @Around("pointCut()")
    public Object around(ProceedingJoinPoint joinPoint) throws Throwable {
        DataSource dataSource = this.getDataSource(joinPoint);
        if (dataSource == null) {
            DataSourceContext.setDataSource(DataSourceType.MASTER);
        } else {
            DataSourceContext.setDataSource(dataSource.value());
        }
        try {
            return joinPoint.proceed();
        } finally {
            DataSourceContext.removeDataSource();
        }
    }

    /**
     * 获取数据源
     *
     * @param joinPoint
     * @return
     */
    public DataSource getDataSource(ProceedingJoinPoint joinPoint) {
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        // 方法上查找注解
        DataSource dataSource = AnnotationUtils.findAnnotation(signature.getMethod(), DataSource.class);
        if (Objects.nonNull(dataSource)) {
            return dataSource;
        }
        // 类上查找注解
        return AnnotationUtils.findAnnotation(signature.getDeclaringType(), DataSource.class);
    }
}

2.5 线程本地变量

package com.qiangesoft.datasource.core;

/**
 * 数据源上下文
 *
 * @author qiangesoft
 * @date 2024-03-14
 */
public class DataSourceContext {

    /**
     * 线程本地变量：数据源
     */
    private static final ThreadLocal<String> CONTEXT_HOLDER = new ThreadLocal<>();

    /**
     * 设置数据源的变量
     */
    public static void setDataSource(DataSourceType dataSourceType) {
        CONTEXT_HOLDER.set(dataSourceType.getType());
    }

    /**
     * 获得数据源的变量
     */
    public static String getDataSource() {
        return CONTEXT_HOLDER.get();
    }

    /**
     * 清空数据源变量
     */
    public static void removeDataSource() {
        CONTEXT_HOLDER.remove();
    }
}

2.6 使用

package com.qiangesoft.datasource.controller;

import com.qiangesoft.datasource.core.DataSource;
import com.qiangesoft.datasource.core.DataSourceType;
import com.qiangesoft.datasource.entity.SysUser;
import com.qiangesoft.datasource.service.ISysUserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

/**
 * <p>
 * 用户信息 前端控制器
 * </p>
 *
 * @author qiangesoft
 * @since 2024-03-14
 */
@RestController
@RequestMapping("/sys/user")
public class SysUserController {

    @Autowired
    private ISysUserService sysUserService;

    @DataSource(DataSourceType.MASTER)
    @GetMapping("/master")
    public List<SysUser> listMaster() {
        return sysUserService.list();
    }

    @DataSource(DataSourceType.SLAVE)
    @GetMapping("/slave")
    public List<SysUser> listSlave() {
        return sysUserService.list();
	}

}