SpringBoot多数据源配置

参考：https://yq.aliyun.com/articles/632079

首先看配置文件：

#spring配置
spring:
  #主数据源
   datasource:
      driver-class-name: com.mysql.jdbc.Driver
      url: jdbc:mysql://server:3306/simon_jia_dev?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&useSSL=false
      username: root
      password: js=123456
      type: com.zaxxer.hikari.HikariDataSource
      hikari:
        maxLifetime: 1765000 #一个连接的生命时长（毫秒），超时而且没被使用则被释放（retired），缺省:30分钟，建议设置比数据库超时时长少30秒以上
        maximumPoolSize: 20 #连接池中允许的最大连接数。缺省值：10；推荐的公式：((core_count * 2) + effective_spindle_count)
        minimumIdle:  1 #连接池中允许的最小空闲连接数
# 更多数据源
custom:
  datasource:
    names: ds1,ds2
    ds1:
      driver-class-name: com.mysql.jdbc.Driver
      url: jdbc:mysql://server:3306/simon_jia_dev?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&useSSL=false
      username: root
      password: 123456
      type: com.zaxxer.hikari.HikariDataSource
      hikari:
        maxLifetime: 1765000 #一个连接的生命时长（毫秒），超时而且没被使用则被释放（retired），缺省:30分钟，建议设置比数据库超时时长少30秒以上
        maximumPoolSize: 20 #连接池中允许的最大连接数。缺省值：10；推荐的公式：((core_count * 2) + effective_spindle_count)
        minimumIdle:  1 #连接池中允许的最小空闲连接数
    ds2:
      driver-class-name: com.mysql.jdbc.Driver
      url: jdbc:mysql://localhost:3306/student?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true&useSSL=false
      username: root
      password: 123456
      type: com.zaxxer.hikari.HikariDataSource
      hikari:
        maxLifetime: 1765000 #一个连接的生命时长（毫秒），超时而且没被使用则被释放（retired），缺省:30分钟，建议设置比数据库超时时长少30秒以上
        maximumPoolSize: 20 #连接池中允许的最大连接数。缺省值：10；推荐的公式：((core_count * 2) + effective_spindle_count)
        minimumIdle:  1 #连接池中允许的最小空闲连接数

注解类

package com.simonjia.common.datasource;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
 * @Author: SimonHu
 * @Date: 2019/11/21 13:41
 * @Description:在方法上使用，用于指定使用哪个数据源
 */
@Target({ ElementType.METHOD, ElementType.TYPE })
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface TargetDataSource {
    String name();
}

动态数据源

package com.simonjia.common.datasource;

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

/**
 * @Author: SimonHu
 * @Date: 2019/11/21 13:37
 * @Description:动态数据源
 */
public class DynamicDataSource extends AbstractRoutingDataSource {
    @Override
    protected Object determineCurrentLookupKey() {
        return DynamicDataSourceContextHolder.getDataSourceType();
    }
}

数据源切面

package com.simonjia.common.datasource;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;
/**
 * @Author: SimonHu
 * @Date: 2019/11/21 13:38
 * @Description:
 */
@Aspect
@Order(-1)// 保证该AOP在@Transactional之前执行
@Component
public class DynamicDataSourceAspect {
    
    private static final Logger logger = LoggerFactory.getLogger(DynamicDataSourceAspect.class);
    
    @Before("@annotation(ds)")
    public void changeDataSource(JoinPoint point, TargetDataSource ds) throws Throwable {
        String dsId = ds.name();
        if (!DynamicDataSourceContextHolder.containsDataSource(dsId)) {
            logger.error("数据源[{}]不存在，使用默认数据源 > {}", ds.name(), point.getSignature());
        } else {
            logger.debug("Use DataSource : {} > {}", ds.name(), point.getSignature());
            DynamicDataSourceContextHolder.setDataSourceType(ds.name());
        }
    }
    
    @After("@annotation(ds)")
    public void restoreDataSource(JoinPoint point, TargetDataSource ds) {
        logger.debug("Revert DataSource : {} > {}", ds.name(), point.getSignature());
        DynamicDataSourceContextHolder.clearDataSourceType();
    }
}

package com.simonjia.common.datasource;

import java.util.ArrayList;
import java.util.List;

/**
 * @Author: SimonHu
 * @Date: 2019/11/21 13:39
 * @Description:
 */
public class DynamicDataSourceContextHolder {
    private static final ThreadLocal<String> contextHolder = new ThreadLocal<String>();
    public static List<String> dataSourceIds = new ArrayList<>();
    
    public static void setDataSourceType(String dataSourceType) {
        contextHolder.set(dataSourceType);
    }
    
    public static String getDataSourceType() {
        return contextHolder.get();
    }
    
    public static void clearDataSourceType() {
        contextHolder.remove();
    }
    
    /**
     * 判断指定DataSrouce当前是否存在
     *
     * @param dataSourceId
     * @return
     * @author SHANHY
     * @create 2016年1月24日
     */
    public static boolean containsDataSource(String dataSourceId) {
        return dataSourceIds.contains(dataSourceId);
    }
}

动态数据源注册

package com.simonjia.common.datasource;
import java.util.HashMap;
import java.util.Map;

import javax.sql.DataSource;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.MutablePropertyValues;
import org.springframework.beans.PropertyValues;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.GenericBeanDefinition;
import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
import org.springframework.boot.bind.RelaxedDataBinder;
import org.springframework.boot.bind.RelaxedPropertyResolver;
import org.springframework.context.EnvironmentAware;
import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.convert.support.DefaultConversionService;
import org.springframework.core.env.Environment;
import org.springframework.core.type.AnnotationMetadata;
/**
 * @Author: SimonHu
 * @Date: 2019/11/21 13:39
 * @Description:动态数据源注册<br/>
 *  * 启动动态数据源请在启动类中（如SpringBootSampleApplication）
 *  * 添加 @Import(DynamicDataSourceRegister.class)
 */
public class DynamicDataSourceRegister implements ImportBeanDefinitionRegistrar, EnvironmentAware{
    private static final Logger logger = LoggerFactory.getLogger(DynamicDataSourceRegister.class);
    
    private ConversionService conversionService = new DefaultConversionService();
    private PropertyValues dataSourcePropertyValues;
    
    // 如配置文件中未指定数据源类型，使用该默认值
    private static final Object DATASOURCE_TYPE_DEFAULT = "org.apache.tomcat.jdbc.pool.DataSource";
    // private static final Object DATASOURCE_TYPE_DEFAULT =
    // "com.zaxxer.hikari.HikariDataSource";
    
    // 数据源
    private DataSource defaultDataSource;
    private Map<String, DataSource> customDataSources = new HashMap<>();
    
    @Override
    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
        Map<Object, Object> targetDataSources = new HashMap<Object, Object>();
        // 将主数据源添加到更多数据源中
        targetDataSources.put("dataSource", defaultDataSource);
        DynamicDataSourceContextHolder.dataSourceIds.add("dataSource");
        // 添加更多数据源
        targetDataSources.putAll(customDataSources);
        for (String key : customDataSources.keySet()) {
            DynamicDataSourceContextHolder.dataSourceIds.add(key);
        }
        
        // 创建DynamicDataSource
        GenericBeanDefinition beanDefinition = new GenericBeanDefinition();
        beanDefinition.setBeanClass(DynamicDataSource.class);
        beanDefinition.setSynthetic(true);
        MutablePropertyValues mpv = beanDefinition.getPropertyValues();
        mpv.addPropertyValue("defaultTargetDataSource", defaultDataSource);
        mpv.addPropertyValue("targetDataSources", targetDataSources);
        registry.registerBeanDefinition("dataSource", beanDefinition);
        
        logger.info("Dynamic DataSource Registry");
    }
    
    /**
     * 创建DataSource
     *
     * @param type
     * @param driverClassName
     * @param url
     * @param username
     * @param password
     * @return
     * @author SHANHY
     * @create 2016年1月24日
     */
    @SuppressWarnings("unchecked")
    public DataSource buildDataSource(Map<String, Object> dsMap) {
        try {
            Object type = dsMap.get("type");
            if (type == null) {
                // 默认DataSource
                type = DATASOURCE_TYPE_DEFAULT;
            }
            Class<? extends DataSource> dataSourceType;
            dataSourceType = (Class<? extends DataSource>) Class.forName((String) type);
            
            String driverClassName = dsMap.get("driver-class-name").toString();
            String url = dsMap.get("url").toString();
            String username = dsMap.get("username").toString();
            String password = dsMap.get("password").toString();
            
            DataSourceBuilder factory = DataSourceBuilder.create().driverClassName(driverClassName).url(url)
                    .username(username).password(password).type(dataSourceType);
            return factory.build();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        return null;
    }
    
    /**
     * 加载多数据源配置
     */
    @Override
    public void setEnvironment(Environment env) {
        initDefaultDataSource(env);
        initCustomDataSources(env);
    }
    
    /**
     * 初始化主数据源
     *
     * @author SHANHY
     * @create 2016年1月24日
     */
    private void initDefaultDataSource(Environment env) {
        // 读取主数据源
        RelaxedPropertyResolver propertyResolver = new RelaxedPropertyResolver(env, "spring.datasource.");
        Map<String, Object> dsMap = new HashMap<>();
        dsMap.put("type", propertyResolver.getProperty("type"));
        dsMap.put("driver-class-name", propertyResolver.getProperty("driver-class-name"));
        dsMap.put("url", propertyResolver.getProperty("url"));
        dsMap.put("username", propertyResolver.getProperty("username"));
        dsMap.put("password", propertyResolver.getProperty("password"));
        
        defaultDataSource = buildDataSource(dsMap);
        
        dataBinder(defaultDataSource, env);
    }
    
    /**
     * 为DataSource绑定更多数据
     *
     * @param dataSource
     * @param env
     * @author SHANHY
     * @create  2016年1月25日
     */
    private void dataBinder(DataSource dataSource, Environment env){
        RelaxedDataBinder dataBinder = new RelaxedDataBinder(dataSource);
        //dataBinder.setValidator(new LocalValidatorFactory().run(this.applicationContext));
        dataBinder.setConversionService(conversionService);
        dataBinder.setIgnoreNestedProperties(false);//false
        dataBinder.setIgnoreInvalidFields(false);//false
        dataBinder.setIgnoreUnknownFields(true);//true
        if(dataSourcePropertyValues == null){
            Map<String, Object> rpr = new RelaxedPropertyResolver(env, "spring.datasource").getSubProperties(".");
            Map<String, Object> values = new HashMap<>(rpr);
            // 排除已经设置的属性
            values.remove("type");
            values.remove("driver-class-name");
            values.remove("url");
            values.remove("username");
            values.remove("password");
            dataSourcePropertyValues = new MutablePropertyValues(values);
        }
        dataBinder.bind(dataSourcePropertyValues);
    }
    
    /**
     * 初始化更多数据源
     *
     * @author SHANHY
     * @create 2016年1月24日
     */
    private void initCustomDataSources(Environment env) {
        // 读取配置文件获取更多数据源，也可以通过defaultDataSource读取数据库获取更多数据源
        RelaxedPropertyResolver propertyResolver = new RelaxedPropertyResolver(env, "custom.datasource.");
        String dsPrefixs = propertyResolver.getProperty("names");
        for (String dsPrefix : dsPrefixs.split(",")) {// 多个数据源
            Map<String, Object> dsMap = propertyResolver.getSubProperties(dsPrefix + ".");
            DataSource ds = buildDataSource(dsMap);
            customDataSources.put(dsPrefix, ds);
            dataBinder(ds, env);
        }
    }
}

启动类加上

@SpringBootApplication
@Import({DynamicDataSourceRegister.class}) // 注册动态多数据源
public class JiaApplication extends WebMvcConfigurerAdapter {

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

}

@TargetDataSource注解不要使用在mapper层

 @TargetDataSource(name="ds2")
    public List<Map> testDataSource(){
        List<Map> list = indexMapper.selectStudent();
        return list;
    }

调用其他数据库成功