mybatis PLUS实现多数据源

Mybatis Plus is a powerful library that simplifies the development of MyBatis applications. To implement multiple data sources with MyBatis Plus, you can follow these steps:

1. Configure data source properties: In your application.properties or application.yml file, define the connection details for each data source. Assign unique names to each data source to differentiate them.

Example:

spring:
  datasource:
    datasource1:
      url: jdbc:mysql://localhost:3306/db1
      username: user1
      password: password1
    datasource2:
      url: jdbc:mysql://localhost:3306/db2
      username: user2
      password: password2

2. Define multiple DataSource objects: Create separate DataSource objects for each data source using the configured properties.

Example:

@Configuration
public class DataSourceConfig {
  
  @ConfigurationProperties(prefix = "spring.datasource.datasource1")
  @Bean(name = "dataSource1")
  public DataSource dataSource1() {
    return DataSourceBuilder.create().build();
  }
  
  @ConfigurationProperties(prefix = "spring.datasource.datasource2")
  @Bean(name = "dataSource2")
  public DataSource dataSource2() {
    return DataSourceBuilder.create().build();
  }
  
}

3. Configure MyBatis session factories: Create SqlSessionFactory objects for each data source using the previously defined DataSources.

Example:

@Configuration
@MapperScan(basePackages = "com.example.mapper1", sqlSessionFactoryRef = "sqlSessionFactory1")
public class MyBatisConfig1 {
  
  @Bean(name = "sqlSessionFactory1")
  public SqlSessionFactory sqlSessionFactory1(@Qualifier("dataSource1") DataSource dataSource1) throws Exception {
    SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
    factoryBean.setDataSource(dataSource1);
    return factoryBean.getObject();
  }
  
}

@Configuration
@MapperScan(basePackages = "com.example.mapper2", sqlSessionFactoryRef = "sqlSessionFactory2")
public class MyBatisConfig2 {
  
  @Bean(name = "sqlSessionFactory2")
  public SqlSessionFactory sqlSessionFactory2(@Qualifier("dataSource2") DataSource dataSource2) throws Exception {
    SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
    factoryBean.setDataSource(dataSource2);
    return factoryBean.getObject();
  }
  
}

4. Configure transaction managers: Create PlatformTransactionManager objects for each data source.

Example:

@Configuration
public class TransactionManagerConfig {
  
  @Bean(name = "transactionManager1")
  public PlatformTransactionManager transactionManager1(@Qualifier("dataSource1") DataSource dataSource1) {
    return new DataSourceTransactionManager(dataSource1);
  }
  
  @Bean(name = "transactionManager2")
  public PlatformTransactionManager transactionManager2(@Qualifier("dataSource2") DataSource dataSource2) {
    return new DataSourceTransactionManager(dataSource2);
  }
  
}

After following these steps, you can use the `@DS` annotation provided by MyBatis Plus to specify the data source for each repository or service method.

Example:

@DS("datasource1")
@Repository
public interface UserMapper1 extends BaseMapper<User> {
  // ...
}

@DS("datasource2")
@Repository
public interface UserMapper2 extends BaseMapper<User> {
  // ...
}

By correctly configuring multiple data sources in MyBatis Plus, you can easily interact with different databases within your application.