Spring Boot配置多數據源並實現Druid自動切換

原文：https://blog.csdn.net/acquaintanceship/article/details/75350653

 

Spring Boot配置多數據源
配置yml文件
主數據源配置
從數據源配置
使用dao
日志
Spring Boot配置多數據源
配置yml文件
這里並沒有對spring.datasource配置數據源，因為增加新數據源后，系統會覆蓋由spring.datasource自動配置的內容。
這里自定義了兩個數據源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 #指定初始化數據源，是否用data.sql來初始化，默認: 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

 

主數據源配置
注意，配置類需要對DataSource、DataSourceTransactionManager、SqlSessionFactory 、SqlSessionTemplate四個數據項進行配置；DataSource類型需要引入javax.sql.DataSource；當系統中有多個數據源時，必須有一個數據源為主數據源，使用@Primary修飾。
@MapperScan對指定dao包建立映射，確保在多個數據源下，自動選擇合適的數據源，而在service層里不需要做特殊說明。

@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);
    }
}

從數據源配置

@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

這里只需要正常使用dao就可以了，spring會根據數據源配置的映射自動選擇相應數據源，而不需要在service做特殊說明。

@Service
public 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