springboot多数据源配置

项目配置

多数据源配置主要用到spring的AbstractRoutingDataSource，网上介绍资料也有很多，这里主要做个备份

maven依赖

除了数据库连接的依赖，spring的依赖，Mybatis的依赖之外还需要

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>1.1.5</version>
</dependency>

使用com.alibaba.druid.spring.boot.autoconfigure.DruidDataSourceBuilder生成DataSource

数据源配置

1. application.properties

   #mysql
   multiple.datasource.mysql0.driver-class-name=com.mysql.jdbc.Driver
   multiple.datasource.mysql0.url=jdbc:mysql://mysql.a15223331219-mysql.svc.bja.ipaas.cn:8066/?useUnicode=true&characterEncoding=utf-8&autoReconnect=true
   multiple.datasource.mysql0.username=proxy
   multiple.datasource.mysql0.password=proxy.ibk
   #sqlserver
   multiple.datasource.sqlserver0.driver-class-name=com.microsoft.sqlserver.jdbc.SQLServerDriver
   multiple.datasource.sqlserver0.url=jdbc:sqlserver://***:1433;
   multiple.datasource.sqlserver0.username=**
   multiple.datasource.sqlserver0.password=***
   # 以下多个数据源
   ....
   

2. 为了方便管理多数据源，我们使用枚举类进行管理

   public enum DataSourceKey {
   	MYSQL0(),
   	SQLSERVER0(),
   	;
   }
   

3. 创建数据源Bean

   @Configuration
   public class DynamicDataSourceConfiguration {
       @Bean
       @ConfigurationProperties(prefix = "multiple.datasource.mysql0")
       public DataSource mysql0() {
           return DruidDataSourceBuilder.create().build();
       }
   
       @Bean
       @ConfigurationProperties(prefix = "multiple.datasource.sqlserver0")
       public DataSource sqlserver0() {
           return DruidDataSourceBuilder.create().build();
       }
   
      /**
        * 核心动态数据源
        *
        * @return 数据源实例
        */
       @Bean
       public DataSource dynamicDataSource() {
       	// 设置默认数据源为mysql0
           DynamicRoutingDataSource dataSource = new DynamicRoutingDataSource();
           dataSource.setDefaultTargetDataSource(mysql0());
           
           Map<Object, Object> dataSourceMap = new HashMap<>(2);
           dataSourceMap.put(DataSourceKey.MYSQL0, mysql0());
           dataSourceMap.put(DataSourceKey.SQLSERVER0, sqlserver0());
           // AbstractRoutingDataSource.setTargetDataSources
           dataSource.setTargetDataSources(dataSourceMap);
           return dataSource;
       }
   
       @Bean
       public SqlSessionFactory sqlSessionFactory() throws Exception {
           SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
           sqlSessionFactoryBean.setDataSource(dynamicDataSource());
           sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/*.xml"));
           return sqlSessionFactoryBean.getObject();
       }
       
       @Bean
       public SqlSessionTemplate sqlSessionTemplate() throws Exception {
           return new SqlSessionTemplate(sqlSessionFactory());
       }
   
       /**
        * 事务管理
        *
        * @return 事务管理实例
        */
       @Bean
       public PlatformTransactionManager platformTransactionManager() {
           return new DataSourceTransactionManager(dynamicDataSource());
       }
   }
   

   此类将多数据源注册到spring容器，且注册到AbstractRoutingDataSource中

   创建sql会话工厂

4. 创建多数据源上下文切换类

   public class DynamicDataSourceContextHolder {
   
       private static final ThreadLocal<DataSourceKey> CURR_DATA_SOURCE = new ThreadLocal<>();
   
       /**
        * 清除当前数据源
        */
       public static void clear() {
           CURR_DATA_SOURCE.remove();
       }
   
       /**
        * 获取当前使用的数据源
        *
        * @return 当前使用数据源的ID
        */
       public static DataSourceKey get() {
           return CURR_DATA_SOURCE.get();
       }
   
       /**
        * 设置当前使用的数据源
        *
        * @param value 需要设置的数据源ID
        */
       public static void set(DataSourceKey value) {
           CURR_DATA_SOURCE.set(value);
       }
   }
   

5. AbstractRoutingDataSource

   public class DynamicRoutingDataSource extends AbstractRoutingDataSource {
       @Override
       protected Object determineCurrentLookupKey() {
           return DynamicDataSourceContextHolder.get();
       }
   }
   

   以上为多数据源配置。在使用时，只需要DynamicDataSourceContextHolder.set(DataSourceKey.MYSQL0);即可实时切换数据源。