在使用 Spring Boot 和 MyBatis 动态切换数据源时遇到的问题以及解决方法

1. org.apache.ibatis.binding.BindingException: Invalid bound statement (not found)

*.xml

SqlSessionFactoryBean

typeAliasesPackage

mapperLocations

@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)

DataSourceConfigure

@Bean    @ConfigurationProperties(prefix = "mybatis")
public SqlSessionFactoryBean sqlSessionFactoryBean() {
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
sqlSessionFactoryBean.setDataSource(dynamicDataSource());
return sqlSessionFactoryBean;
}

@Bean
public SqlSessionFactoryBean sqlSessionFactoryBean() {
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
sqlSessionFactoryBean.setTypeAliasesPackage("typeAliasesPackage");
sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("mapperLocations"));
sqlSessionFactoryBean.setDataSource(dynamicDataSource());
return sqlSessionFactoryBean;
}

2. Consider marking one of the beans as @Primary, updating the consumer to accept multiple beans, or using @Qualifier to identify the bean that should be consumed

DataSource

Bean

@Primary

Bean

DataSourceBuilder.create().build()

Bean

new AbstractRoutingDataSource

Bean

master()

slave()

DataSource

dynamicDataSource()

DataSource

3. 通过注解方式动态切换数据源无效

Bean

@Bean("dynamicDataSource")
public DataSource dynamicDataSource() {
DynamicRoutingDataSource dynamicRoutingDataSource = new DynamicRoutingDataSource();
Map<Object, Object> dataSourceMap = new HashMap<>(2);
dataSourceMap.put("master", master());
dataSourceMap.put("slave", slave());

// Set master datasource as default
dynamicRoutingDataSource.setDefaultTargetDataSource(master());
// Set master and slave datasource as target datasource
dynamicRoutingDataSource.setTargetDataSources(dataSourceMap);
// To put datasource keys into DataSourceContextHolder to judge if the datasource is exist
DynamicDataSourceContextHolder.dataSourceKeys.addAll(dataSourceMap.keySet());
}
return dynamicRoutingDataSource;
}
@Bean
@ConfigurationProperties(prefix = "mybatis")
public SqlSessionFactoryBean sqlSessionFactoryBean() {
SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
// Here is very important, if don't config this, will can't switch datasource
// put all datasource into SqlSessionFactoryBean, then will autoconfig SqlSessionFactory
sqlSessionFactoryBean.setDataSource(dynamicDataSource());
return sqlSessionFactoryBean;
}

4.

@Transactional

注解无效，发生异常不回滚

Bean

@Transactional

rollbackFor

@Bean
public PlatformTransactionManager transactionManager() {
return new DataSourceTransactionManager(dynamicDataSource());
}

5. 通过 AOP 判断 DAO 层方法名时切换数据源无效

@Transactional

@Transactional

DataSourceTransactionManager

@Bean
public PlatformTransactionManager transactionManager() {
return new DataSourceTransactionManager(dynamicDataSource());
}

6. The dependencies of some of the beans in the application context form a cycle

The dependencies of some of the beans in the application context form a cycle:
produceController (field private cn.com.hellowood.dynamicdatasource.service.ProductService cn.com.hellowood.dynamicdatasource.controller.ProduceController.productService)
↓
productService (field private cn.com.hellowood.dynamicdatasource.mapper.ProductDao cn.com.hellowood.dynamicdatasource.service.ProductService.productDao)
↓
productDao defined in file [/Users/hehuimin/Downloads/Dev/SpringBoot/DynamicDataSource/out/production/classes/cn/com/hellowood/dynamicdatasource/mapper/ProductDao.class]
↓
sqlSessionFactoryBean defined in class path resource [cn/com/hellowood/dynamicdatasource/configuration/DataSourceConfigurer.class]
┌─────┐
|  dynamicDataSource defined in class path resource [cn/com/hellowood/dynamicdatasource/configuration/DataSourceConfigurer.class]
↑
↓
|  master defined in class path resource [cn/com/hellowood/dynamicdatasource/configuration/DataSourceConfigurer.class]
↑
↓
|  dataSourceInitializer
└─────┘

DataSource

@Primary

/**
* master DataSource
* @Primary 注解用于标识默认使用的 DataSource Bean，因为有三个 DataSource Bean，该注解可用于 master
* 或 slave DataSource Bean, 但不能用于 dynamicDataSource Bean, 否则会产生循环调用
*      * @ConfigurationProperties 注解用于从 application.properties 文件中读取配置，为 Bean 设置属性
* @return data source
*/
@Bean("master")
@Primary
@ConfigurationProperties(prefix = "application.server.db.master")
public DataSource master() {
return DataSourceBuilder.create().build();

}    @Bean("slave")
@ConfigurationProperties(prefix = "application.server.db.slave")
public DataSource slave() {
return DataSourceBuilder.create().build();

}    @Bean("dynamicDataSource")
public DataSource dynamicDataSource() {
DynamicRoutingDataSource dynamicRoutingDataSource = new DynamicRoutingDataSource();
Map<Object, Object> dataSourceMap = new HashMap<>(2);
dataSourceMap.put("master", master());
dataSourceMap.put("slave", slave());

// Set master datasource as default
dynamicRoutingDataSource.setDefaultTargetDataSource(master());
// Set master and slave datasource as target datasource
dynamicRoutingDataSource.setTargetDataSources(dataSourceMap);

// To put datasource keys into DataSourceContextHolder to judge if the datasource is exist
DynamicDataSourceContextHolder.dataSourceKeys.addAll(dataSourceMap.keySet());
return dynamicRoutingDataSource;

}