Spring Boot配置多数据源并实现Druid自动切换

Spring Boot配置多数据源

配置yml文件

这里并没有对spring.datasource配置数据源，因为增加新数据源后，系统会覆盖由spring.datasource自动配置的内容。
这里自定义了两个数据源spring.datasource.cmmi和spring.datasource.zentao

spring:  datasource:    type: com.alibaba.druid.pool.DruidDataSource    base:      type: com.alibaba.druid.pool.DruidDataSource      driver-class-name: com.mysql.cj.jdbc.Driver      initialize: true #指定初始化数据源，是否用data.sql来初始化，默认: true      name: cmmi      url: jdbc:mysql://127.0.0.1:3306/cmmi?useUnicode=true&characterEncoding=utf-8&useSSL=false&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC&zeroDateTimeBehavior=convertToNull      username: root      password: root    zentao:      type: com.alibaba.druid.pool.DruidDataSource      driver-class-name: com.mysql.cj.jdbc.Driver      initialize: true      name: zentaopro      url: jdbc:mysql://127.0.0.1:3306/zentaopro?useUnicode=true&characterEncoding=utf-8&useSSL=false&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC&zeroDateTimeBehavior=convertToNull      username: root      password: root

主数据源配置

注意，配置类需要对DataSource、DataSourceTransactionManager、SqlSessionFactory 、SqlSessionTemplate四个数据项进行配置；DataSource类型需要引入javax.sql.DataSource；当系统中有多个数据源时，必须有一个数据源为主数据源，使用@Primary修饰。
@MapperScan对指定dao包建立映射，确保在多个数据源下，自动选择合适的数据源，而在service层里不需要做特殊说明。

@Configuration@MapperScan(basePackages = "cmmi.dao.base", sqlSessionTemplateRef = "baseSqlSessionTemplate")public class BaseDataSourceConfig {    @Bean(name = "baseDataSource")    @ConfigurationProperties(prefix = "spring.datasource.base")    @Primary    public DataSource setDataSource() {        return DataSourceBuilder.create().build();    }    @Bean(name = "baseTransactionManager")    @Primary    public DataSourceTransactionManager setTransactionManager(@Qualifier("baseDataSource") DataSource dataSource) {        return new DruidDataSource();    }    @Bean(name = "baseSqlSessionFactory")    @Primary    public SqlSessionFactory setSqlSessionFactory(@Qualifier("baseDataSource") DataSource dataSource) throws Exception {        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();        bean.setDataSource(dataSource);        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/base/*.xml"));        return bean.getObject();    }    @Bean(name = "baseSqlSessionTemplate")    @Primary    public SqlSessionTemplate setSqlSessionTemplate(@Qualifier("baseSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {        return new SqlSessionTemplate(sqlSessionFactory);    }}

从数据源配置

@Configuration@MapperScan(basePackages = "cmmi.dao.zentao", sqlSessionTemplateRef = "zentaoSqlSessionTemplate")public class ZentaoDataSourceConfig {    @Bean(name = "zentaoDataSource")    @ConfigurationProperties(prefix = "spring.datasource.zentao")    public DataSource setDataSource() {        return new DruidDataSource();    }    @Bean(name = "zentaoTransactionManager")    public DataSourceTransactionManager setTransactionManager(@Qualifier("zentaoDataSource") DataSource dataSource) {        return new DataSourceTransactionManager(dataSource);    }    @Bean(name = "zentaoSqlSessionFactory")    public SqlSessionFactory setSqlSessionFactory(@Qualifier("zentaoDataSource") DataSource dataSource) throws Exception {        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();        bean.setDataSource(dataSource);        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/zentao/*.xml"));        return bean.getObject();    }    @Bean(name = "zentaoSqlSessionTemplate")    public SqlSessionTemplate setSqlSessionTemplate(@Qualifier("zentaoSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {        return new SqlSessionTemplate(sqlSessionFactory);    }}

使用dao

这里只需要正常使用dao就可以了，spring会根据数据源配置的映射自动选择相应数据源，而不需要在service做特殊说明。

@Servicepublic class TestService {    private final ZtUserMapper ztUserMapper;    private final LevelDic levelDic;    @Autowired    public TestService(ZtUserMapper ztUserMapper, LevelDic levelDic) {        this.ztUserMapper = ztUserMapper;        this.levelDic = levelDic;    }    public void test() {        ztUserMapper.selectByPrimaryKey(1);        levelDic.setDicId(new Integer(1).byteValue());    }}

日志

o.a.c.c.C.[Tomcat].[localhost].[/cmmi] : Initializing Spring FrameworkServlet ‘dispatcherServlet’
o.s.web.servlet.DispatcherServlet : FrameworkServlet ‘dispatcherServlet’: initialization started
o.s.web.servlet.DispatcherServlet : FrameworkServlet ‘dispatcherServlet’: initialization completed in 23 ms
com.alibaba.druid.pool.DruidDataSource : {dataSource-1,cmmi} inited
com.alibaba.druid.pool.DruidDataSource : {dataSource-2,zentaopro} inited