Spring Mabatis 多数据源配置

实际的业务场景中，有时需要使用多数据源，我们看看如何快速地进行配置。

基础环境

Spring boot 2.1.1.RELEASE

Mybatis 1.3.1

HikariCP 3.1.0

pom文件

    <properties>
    <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.1</version>
        </dependency>

        <dependency>
            <groupId>com.zaxxer</groupId>
            <artifactId>HikariCP</artifactId>
            <version>3.1.0</version>
        </dependency>

        <dependency>
            <groupId>javax.inject</groupId>
            <artifactId>javax.inject</artifactId>
            <version>1</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

主要配置

1 application.properties

spring.datasource.primary.jdbc-url=url1
spring.datasource.primary.username=usr1
spring.datasource.primary.password=pw1
spring.datasource.schema.jdbc-url=url2
spring.datasource.schema.username=usr2
spring.datasource.schema.password=pw2

注意配置多数据源时，url的key需要配置成jdbc-url

2 数据库连接池配置类

DatabaseConfiguration.java
用于使用不同url连接池的实例化

@Configuration
public class DatabaseConfiguration {

    public static final String PRIMARY_DATASOURCE = "PriDS";
    public static final String METADATA_DATASOURCE = "MetaDS";

    @Bean(name = PRIMARY_DATASOURCE, destroyMethod = "")
    @ConfigurationProperties(prefix = "spring.datasource.primary")
    @Primary
    public DataSource dataSourcePrimary(){
        return new HikariDataSource();
    }

    @Bean(name = METADATA_DATASOURCE, destroyMethod = "")
    @ConfigurationProperties(prefix = "spring.datasource.schema")
    public DataSource dataSourceMetadata(){
        return new HikariDataSource();
    }

}

3 创建Mybatis mapper bean配置类

MyBatisConfiguration.java

@Configuration
@MapperScan("com.example.multiDatasourceDemo.mapper")
public class MyBatisConfiguration {
    public static final String PRIMARY_SESSION_FACTORY = "primarySessionFactory";
    public static final String METADATA_SESSION_FACTORY = "metadataSessionFactory";

    /*primary datasource factory bean,use @MapperScan for creating mapper bean */
    @Bean(name = PRIMARY_SESSION_FACTORY)
    @Primary
    public SqlSessionFactoryBean primarySqlSessionFactory(
            @Named(DatabaseConfiguration.PRIMARY_DATASOURCE)final DataSource primaryDataSource) throws Exception{
        final SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(primaryDataSource);
        VFS.addImplClass(SpringBootVFS.class);
        PathMatchingResourcePatternResolver pathM3R = new PathMatchingResourcePatternResolver();
        sqlSessionFactoryBean.setMapperLocations(pathM3R.getResources("classpath:mapper/**/*Mapper.xml"));
        sqlSessionFactoryBean.setTypeAliasesPackage("com.example.multiDatasourceDemo.domain");
        SqlSessionFactory sqlSessionFactory;
        sqlSessionFactory = sqlSessionFactoryBean.getObject();
        return sqlSessionFactoryBean;
    }

    /*another datasource factory bean*/
    @Bean(name = METADATA_SESSION_FACTORY)
    public SqlSessionFactoryBean metaSqlSessionFactory(
            @Named(DatabaseConfiguration.METADATA_DATASOURCE) final DataSource anotherDataSource) throws Exception {
        final SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(anotherDataSource);
        VFS.addImplClass(SpringBootVFS.class);
        PathMatchingResourcePatternResolver pathM3R = new PathMatchingResourcePatternResolver();
        sqlSessionFactoryBean.setMapperLocations(pathM3R.getResources("classpath:anothermapper/anotherMapper.xml"));
        sqlSessionFactoryBean.setTypeAliasesPackage("com.example.multiDatasourceDemo.domain");
        final SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBean.getObject();
        return sqlSessionFactoryBean;
    }

    @Bean
    public MapperFactoryBean<AnotherMapper> dbMapper(
            @Named(METADATA_SESSION_FACTORY) final SqlSessionFactoryBean sqlSessionFactoryBean) throws Exception {
        MapperFactoryBean<AnotherMapper> factoryBean = new MapperFactoryBean<>(AnotherMapper.class);
        factoryBean.setSqlSessionFactory(sqlSessionFactoryBean.getObject());
        return factoryBean;
    }
}

创建两个使用不同连接池的工厂bean，作用是通以此创建mapper bean。其中primaryDataSource使用了@MapperScan注解进行mapper class的扫描，在需要被扫描的mapper class上添加@Mapper注解。在项目中mapper数量较多的情况下使用此方式，减少手动创建的代码量。anotherDataSource实例化的mapper使用手动创建的方式，即dbMapper方法，指定了mapper class。

此外如果sql在xml文件内，需要配置setMapperLocations，将xml文件路径配置成要扫描的内容。

setTypeAliasesPackage用于配置sql中使用的resultType当参数的类的包路径，配置后使用时只需要写类名即可。否则需要写完整的包路径和类名。当整个项目打包jar文件后，setTypeAliasesPackage配置不生效，导致部分类扫描不到，需要添加VFS.addImplClass(SpringBootVFS.class)配置。

4 使用实例

详见github的项目，包含测试的controller、mapper、sql与测试用例

参考链接

https://medium.com/@d.lopez.j...

项目地址

https://github.com/tifazxy/Mu...