springboot2 + mybatis 多種方式實現多資料配置
阿新 • • 發佈:2020-03-30
業務系統複雜程度增加,為了解決資料庫I/O瓶頸,很自然會進行拆庫拆表分服務來應對。這就會出現一個系統中可能會訪問多處資料庫,需要配置多個數據源。
第一種場景:專案服務從其它多處資料庫取基礎資料進行業務處理,因此各庫之間不會出現重表等情況。
第二種場景:為了減輕寫入壓力進行讀寫分庫,讀走從庫,寫為主庫。此種表名等資訊皆為一致。
第三種場景:以上兩種皆有。對於某些業務需要大資料量的彙總統計,希望不影響正常業務必須走從庫(表資訊一致),某些配置資訊不存在讀寫壓力,出現不分庫(表資訊不一致)
專案原始碼:
https://github.com/zzsong/springboot-multiple-datasource.git
有三個目錄:
one:
直接使用多@Bean配置,@MapperScan來路徑區分讀何庫
two:
使用註解的方式來標識走何dataSource,AOP攔截注入動態資料來源
third:
使用spring的Bean命名策略進行區分資料來源
專案技術選型: springBoot2.2.5 + mybatis + druid + mysql
先看主要的pom包
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.5.RELEASE</version> <relativePath/> </parent> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-aop</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.1.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.19</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>1.1.21</version> </dependency>
application.yml
spring: datasource: druid: core: url: jdbc:mysql:///kc_core?characterEncoding=utf-8&serverTimezone=Asia/Shanghai username: root password: 123456 driver-class-name: com.mysql.cj.jdbc.Driver type: com.alibaba.druid.pool.DruidDataSource schedule: url: jdbc:mysql:///kc_schedule?characterEncoding=utf-8&serverTimezone=Asia/Shanghai username: root password: 123456 driver-class-name: com.mysql.cj.jdbc.Driver type: com.alibaba.druid.pool.DruidDataSource
mysql新版本必須帶有serverTimezone,不然會報連線異常。
第一種:通過@MapperScans 掃描匹配相關的資料來源
@Configuration @MapperScans({ @MapperScan(basePackages = "com.zss.one.mapper.core", sqlSessionTemplateRef = "coreSqlSessionTemplate",sqlSessionFactoryRef = "coreSqlSessionFactory"), @MapperScan(basePackages = "com.zss.one.mapper.schedule", sqlSessionTemplateRef = "scheduleSqlSessionTemplate",sqlSessionFactoryRef = "scheduleSqlSessionFactory") }) public class MybatisOneConfig { @Bean @ConfigurationProperties(prefix = "spring.datasource.druid.core") public DataSource coreDataSource(){ return DruidDataSourceBuilder.create().build(); } @Bean public SqlSessionFactory coreSqlSessionFactory(@Qualifier("coreDataSource") DataSource coreDataSource) throws Exception { SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean(); sessionFactory.setDataSource(coreDataSource); sessionFactory.getObject().getConfiguration().setJdbcTypeForNull(null); sessionFactory.getObject().getConfiguration().setMapUnderscoreToCamelCase(true); return sessionFactory.getObject(); } @Bean public SqlSessionTemplate coreSqlSessionTemplate(@Qualifier("coreSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception { return new SqlSessionTemplate(sqlSessionFactory); } //======schedule======== @Bean @ConfigurationProperties(prefix = "spring.datasource.druid.schedule") public DataSource scheduleDataSource(){ return DruidDataSourceBuilder.create().build(); } @Bean public SqlSessionFactory scheduleSqlSessionFactory(@Qualifier("scheduleDataSource") DataSource coreDataSource) throws Exception { SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean(); sessionFactory.setDataSource(coreDataSource); sessionFactory.getObject().getConfiguration().setJdbcTypeForNull(null); sessionFactory.getObject().getConfiguration().setMapUnderscoreToCamelCase(true); return sessionFactory.getObject(); } @Bean public SqlSessionTemplate scheduleSqlSessionTemplate(@Qualifier("scheduleSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception { return new SqlSessionTemplate(sqlSessionFactory); } }
第二種是動態資料來源模式,通過AOP切入註解引導使用何資料來源。用自定義註解@interface來標識方法走對應的資料來源。
注意事項:類中的方法再呼叫帶資料來源的方法,不能被AOP切入
@Target({ElementType.METHOD, ElementType.TYPE}) @Retention(RetentionPolicy.RUNTIME) @Documented public @interface TargetDataSource { String value(); }
extends spring的動態DataSource路由來匹配
public class DynamicDataSource extends AbstractRoutingDataSource { @Override protected Object determineCurrentLookupKey() { return DataSourceContextRouting.getDataSourceName(); } }
@Configuration //@EnableConfigurationProperties(MybatisProperties.class)//不要使用此公共配置,Configuration會破壞相關dataSource的配置 @MapperScan("com.zss.two.mapper") public class MybatisConfig { @Bean @ConfigurationProperties(prefix = "spring.datasource.druid.core") public DataSource coreDataSource() { return DruidDataSourceBuilder.create().build(); } @Bean @ConfigurationProperties(prefix = "spring.datasource.druid.schedule") public DataSource scheduleDataSource() { return DruidDataSourceBuilder.create().build(); } @Autowired @Qualifier("coreDataSource") private DataSource coreDataSource; @Autowired @Qualifier("scheduleDataSource") private DataSource scheduleDataSource; @Bean public DynamicDataSource dataSource() { Map<Object, Object> targetDataSources = new HashMap<>(); targetDataSources.put(DataSourceConstants.CORE_DATA_SOURCE, coreDataSource); targetDataSources.put(DataSourceConstants.SCHEDULE_DATA_SOURCE, scheduleDataSource); DynamicDataSource dataSource = new DynamicDataSource(); //設定資料來源對映 dataSource.setTargetDataSources(targetDataSources); //// 設定預設資料來源,當無法對映到資料來源時會使用預設資料來源 dataSource.setDefaultTargetDataSource(coreDataSource); dataSource.afterPropertiesSet(); return dataSource; } /** * 根據資料來源建立SqlSessionFactory */ @Bean public SqlSessionFactory sqlSessionFactory(DynamicDataSource dataSource) throws Exception { SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean(); sessionFactory.setDataSource(dataSource); sessionFactory.getObject().getConfiguration().setJdbcTypeForNull(null); sessionFactory.getObject().getConfiguration().setMapUnderscoreToCamelCase(true); return sessionFactory.getObject(); } @Bean public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory) throws Exception { return new SqlSessionTemplate(sqlSessionFactory); }
第三種,自定義Bean命名策略,按beanName進行自動匹配使用資料來源
@Component public class CoreBeanNameGenerator implements BeanNameGenerator { @Override public String generateBeanName(BeanDefinition definition, BeanDefinitionRegistry registry) { return "core"+ ClassUtils.getShortName(definition.getBeanClassName()); } } @Component public class ScheduleBeanNameGenerator implements BeanNameGenerator { @Override public String generateBeanName(BeanDefinition definition, BeanDefinitionRegistry registry) { return "schedule"+ ClassUtils.getShortName(definition.getBeanClassName()); } }
使用mybatis MapperScannerConfigurer自動掃描,將Mapper介面生成注入到spring
@Bean public MapperScannerConfigurer coreMapperScannerConfig(CoreBeanNameGenerator coreBeanNameGenerator){ MapperScannerConfigurer configurer = new MapperScannerConfigurer(); configurer.setNameGenerator(coreBeanNameGenerator); configurer.setBasePackage("com.zss.third.mapper.core,com.zss.third.mapper.order"); configurer.setSqlSessionFactoryBeanName("coreSqlSessionFactory"); configurer.setSqlSessionTemplateBeanName("coreSqlSessionTemplate"); return configurer; } @Bean public MapperScannerConfigurer scheduleMapperScannerConfig(ScheduleBeanNameGenerator scheduleBeanNameGenerator){ MapperScannerConfigurer configurer = new MapperScannerConfigurer(); configurer.setNameGenerator(scheduleBeanNameGenerator); configurer.setBasePackage("com.zss.third.mapper.schedule,com.zss.third.mapper.order"); configurer.setSqlSessionFactoryBeanName("scheduleSqlSessionFactory"); configurer.setSqlSessionTemplateBeanName("scheduleSqlSessionTemplate"); return configurer; }
到此,三種多資料來源匹配主要點介紹完,詳細直接下載github專案。 在resources/db含有相關測試表及資料指令碼。
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