# :-: 动态添加移除数据源 * [基础介绍](https://www.kancloud.cn/tracy5546/dynamic-datasource/2268595#_2) * [使用步骤](https://www.kancloud.cn/tracy5546/dynamic-datasource/2268595#_6) * [示例项目](https://www.kancloud.cn/tracy5546/dynamic-datasource/2268595#_144) * [源码分析](https://www.kancloud.cn/tracy5546/dynamic-datasource/2268595#_148) # 基础介绍 主要在多租户场景中，常常新的一个租户进来需要动态的添加一个数据源到库中，使得系统不用重启即可切换数据源。 # 使用步骤 ~~~ import com.baomidou.dynamic.datasource.DynamicRoutingDataSource; import com.baomidou.dynamic.datasource.creator.*; import com.baomidou.dynamic.datasource.spring.boot.autoconfigure.DataSourceProperty; import com.baomidou.samples.ds.dto.DataSourceDTO; import io.swagger.annotations.Api; import io.swagger.annotations.ApiOperation; import org.springframework.beans.BeanUtils; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.validation.annotation.Validated; import org.springframework.web.bind.annotation.*; import javax.sql.DataSource; import java.util.Set; @RestController @RequestMapping("/datasources") @Api(tags = "添加删除数据源") public class DataSourceController { @Autowired private DataSource dataSource; // private final DataSourceCreator dataSourceCreator; //3.3.1及以下版本使用这个通用 @Autowired private DefaultDataSourceCreator dataSourceCreator; @Autowired private BasicDataSourceCreator basicDataSourceCreator; @Autowired private JndiDataSourceCreator jndiDataSourceCreator; @Autowired private DruidDataSourceCreator druidDataSourceCreator; @Autowired private HikariDataSourceCreator hikariDataSourceCreator; @Autowired private BeeCpDataSourceCreator beeCpDataSourceCreator; @Autowired private Dbcp2DataSourceCreator dbcp2DataSourceCreator; @GetMapping @ApiOperation("获取当前所有数据源") public Set<String> now() { DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; return ds.getCurrentDataSources().keySet(); } //通用数据源会根据maven中配置的连接池根据顺序依次选择。 //默认的顺序为druid>hikaricp>beecp>dbcp>spring basic @PostMapping("/add") @ApiOperation("通用添加数据源（推荐）") public Set<String> add(@Validated @RequestBody DataSourceDTO dto) { DataSourceProperty dataSourceProperty = new DataSourceProperty(); BeanUtils.copyProperties(dto, dataSourceProperty); DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; DataSource dataSource = dataSourceCreator.createDataSource(dataSourceProperty); ds.addDataSource(dto.getPollName(), dataSource); return ds.getCurrentDataSources().keySet(); } @PostMapping("/addBasic(强烈不推荐，除了用了马上移除)") @ApiOperation(value = "添加基础数据源", notes = "调用Springboot内置方法创建数据源，兼容1,2") public Set<String> addBasic(@Validated @RequestBody DataSourceDTO dto) { DataSourceProperty dataSourceProperty = new DataSourceProperty(); BeanUtils.copyProperties(dto, dataSourceProperty); DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; DataSource dataSource = basicDataSourceCreator.createDataSource(dataSourceProperty); ds.addDataSource(dto.getPollName(), dataSource); return ds.getCurrentDataSources().keySet(); } @PostMapping("/addJndi") @ApiOperation("添加JNDI数据源") public Set<String> addJndi(String pollName, String jndiName) { DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; DataSource dataSource = jndiDataSourceCreator.createDataSource(jndiName); ds.addDataSource(pollName, dataSource); return ds.getCurrentDataSources().keySet(); } @PostMapping("/addDruid") @ApiOperation("基础Druid数据源") public Set<String> addDruid(@Validated @RequestBody DataSourceDTO dto) { DataSourceProperty dataSourceProperty = new DataSourceProperty(); BeanUtils.copyProperties(dto, dataSourceProperty); dataSourceProperty.setLazy(true); DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; DataSource dataSource = druidDataSourceCreator.createDataSource(dataSourceProperty); ds.addDataSource(dto.getPollName(), dataSource); return ds.getCurrentDataSources().keySet(); } @PostMapping("/addHikariCP") @ApiOperation("基础HikariCP数据源") public Set<String> addHikariCP(@Validated @RequestBody DataSourceDTO dto) { DataSourceProperty dataSourceProperty = new DataSourceProperty(); BeanUtils.copyProperties(dto, dataSourceProperty); dataSourceProperty.setLazy(true);//3.4.0版本以下如果有此属性，需手动设置，不然会空指针。 DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; DataSource dataSource = hikariDataSourceCreator.createDataSource(dataSourceProperty); ds.addDataSource(dto.getPollName(), dataSource); return ds.getCurrentDataSources().keySet(); } @PostMapping("/addBeeCp") @ApiOperation("基础BeeCp数据源") public Set<String> addBeeCp(@Validated @RequestBody DataSourceDTO dto) { DataSourceProperty dataSourceProperty = new DataSourceProperty(); BeanUtils.copyProperties(dto, dataSourceProperty); dataSourceProperty.setLazy(true);//3.4.0版本以下如果有此属性，需手动设置，不然会空指针。 DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; DataSource dataSource = beeCpDataSourceCreator.createDataSource(dataSourceProperty); ds.addDataSource(dto.getPollName(), dataSource); return ds.getCurrentDataSources().keySet(); } @PostMapping("/addDbcp") @ApiOperation("基础Dbcp数据源") public Set<String> addDbcp(@Validated @RequestBody DataSourceDTO dto) { DataSourceProperty dataSourceProperty = new DataSourceProperty(); BeanUtils.copyProperties(dto, dataSourceProperty); dataSourceProperty.setLazy(true);//3.4.0版本以下如果有此属性，需手动设置，不然会空指针。 DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; DataSource dataSource = dbcp2DataSourceCreator.createDataSource(dataSourceProperty); ds.addDataSource(dto.getPollName(), dataSource); return ds.getCurrentDataSources().keySet(); } @DeleteMapping @ApiOperation("删除数据源") public String remove(String name) { DynamicRoutingDataSource ds = (DynamicRoutingDataSource) dataSource; ds.removeDataSource(name); return "删除成功"; } } ~~~ # 示例项目 [https://github.com/dynamic-datasource/dynamic-datasource-samples/tree/master/add-remove-datasource-sample](https://github.com/dynamic-datasource/dynamic-datasource-samples/tree/master/add-remove-datasource-sample) # 源码分析  ~~~ public interface DataSourceCreator { /** * 通过属性创建数据源 * * @param dataSourceProperty 数据源属性 * @return 被创建的数据源 */ DataSource createDataSource(DataSourceProperty dataSourceProperty); /** * 当前创建器是否支持根据此属性创建 * * @param dataSourceProperty 数据源属性 * @return 是否支持 */ boolean support(DataSourceProperty dataSourceProperty); } ~~~ DataSourceCreator是一个接口，定义了根据参数创建数据源的接口。 其他creator实现此接口，本项目暂时实现了Druid和Hikaricp的等连接池的实现。 BasicDataSourceCreator 是调用Spring原生的创建方式，只支持最最原始的基础配置。 DefaultDataSourceCreator 是一个通用的创建器，其根据环境自动选择连接池，