记一次配置SpringBoot多数据源

1.数据库连接信息配置

#master数据库
spring.datasource.druid.master.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.druid.master.jdbc-url=jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=UTC
spring.datasource.druid.master.username=root
spring.datasource.druid.master.password=root
#slave数据库
spring.datasource.druid.slave.driver-class-name=oracle.jdbc.OracleDriver
spring.datasource.druid.slave.jdbc-url=jdbc:oracle:thin:@127.0.0.1:1521/orcl
spring.datasource.druid.slave.username=wbs
spring.datasource.druid.slave.password=wbs

2.动态数据源配置

@EnableAutoConfiguration(exclude = { DataSourceAutoConfiguration.class })
@Configuration
@MapperScan(basePackages = "com.**.dao.mapper")
public class DataSourceConfig {

    @Bean(DataSourceConstants.DS_KEY_MASTER)
    @ConfigurationProperties(prefix = "spring.datasource.druid.master")
    public DataSource masterDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(DataSourceConstants.DS_KEY_SLAVE)
    @ConfigurationProperties(prefix = "spring.datasource.druid.slave")
    public DataSource slaveDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean
    @Primary
    public DataSource dynamicDataSource() {
        Map dataSourceMap = new HashMap<>(2);
        dataSourceMap.put(DataSourceConstants.DS_KEY_MASTER, masterDataSource());
        dataSourceMap.put(DataSourceConstants.DS_KEY_SLAVE, slaveDataSource());
        //设置动态数据源
        DynamicDataSource dynamicDataSource = new DynamicDataSource();
        dynamicDataSource.setTargetDataSources(dataSourceMap);
        dynamicDataSource.setDefaultTargetDataSource(masterDataSource());
        return dynamicDataSource;
    }

}

public class DynamicDataSource extends AbstractRoutingDataSource {
    @Override
    protected Object determineCurrentLookupKey() {
        return DynamicDataSourceContextHolder.getContextKey();
    }
}

3.动态选择数据源

public class DynamicDataSourceContextHolder {

    
    private static final ThreadLocal DATASOURCE_CONTEXT_KEY_HOLDER = new ThreadLocal<>();

    
    public static void setContextKey(String key){
        System.out.println("切换数据源"+key);
        DATASOURCE_CONTEXT_KEY_HOLDER.set(key);
    }

    
    public static String getContextKey(){
        String key = DATASOURCE_CONTEXT_KEY_HOLDER.get();
        return key == null?DataSourceConstants.DS_KEY_MASTER:key;
    }

    
    public static void removeContextKey(){
        DATASOURCE_CONTEXT_KEY_HOLDER.remove();
    }
}

public class DataSourceConstants {
    
    public static final String DS_KEY_MASTER = "master";
    
    public static final String DS_KEY_SLAVE = "slave";
}

4.使用 AOP 选择数据源

定义数据源注解

@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD})
public @interface DS {
    String value() default DataSourceConstants.DS_KEY_MASTER;
}

定义数据源切面

@Aspect
@Component
@Order(-100)
public class DynamicDataSourceAspect {
    private  static final Logger loger = LoggerFactory.getLogger(DynamicDataSourceAspect.class);

    @Pointcut("@annotation(com.lhzw.platform.core.common.aop.annotation.DS)")
    public void dataSourcePointCut(){

    }

    @Around("dataSourcePointCut()")
    public Object around(ProceedingJoinPoint joinPoint) throws Throwable {
        String dsKey = getDSAnnotation(joinPoint).value();
        DynamicDataSourceContextHolder.setContextKey(dsKey);
        try{
            return joinPoint.proceed();
        }finally {
            DynamicDataSourceContextHolder.removeContextKey();
        }
    }

    
    private DS getDSAnnotation(ProceedingJoinPoint joinPoint){
        Class targetClass = joinPoint.getTarget().getClass();
        DS dsAnnotation = targetClass.getAnnotation(DS.class);
        // 先判断类的注解，再判断方法注解
        if(Objects.nonNull(dsAnnotation)){
            return dsAnnotation;
        }else{
            MethodSignature methodSignature = (MethodSignature)joinPoint.getSignature();
            return methodSignature.getMethod().getAnnotation(DS.class);
        }
    }
}

5.使用自定义注解进行数据源切换

	@DS(DataSourceConstants.DS_KEY_SLAVE)
    @Override
    public List> list() {
        return testOrclMapper.list();
    }

    @Override
    public List> list1() {
        return testOrclMapper.list1();
    }