SpringBoot 配置动态数据源

数据源配置文件，数据库连接池使用Druid。

spring:
    datasource:
        type: com.alibaba.druid.pool.DruidDataSource
        driverClassName: oracle.jdbc.OracleDriver
        druid:
            first:  #数据源1
                url: jdbc:oracle:thin:@127.0.0.1:1521:orcl
                username: root
                password: root
            second:  #数据源2
                url: jdbc:oracle:thin:@127.0.0.1:1521:orcl
                username: root
                password: root
            initial-size: 10
            max-active: 100
            min-idle: 10
            max-wait: 60000
            pool-prepared-statements: true
            max-pool-prepared-statement-per-connection-size: 20
            time-between-eviction-runs-millis: 60000
            min-evictable-idle-time-millis: 300000
            validation-query: SELECT 1 FROM DUAL
            test-while-idle: true
            test-on-borrow: false
            test-on-return: false
            stat-view-servlet:
                enabled: true
                url-pattern: /druid/*
                #login-username: admin
                #login-password: admin
            filter:
                stat:
                    log-slow-sql: true
                    slow-sql-millis: 1000
                    merge-sql: true
                wall:
                    config:
                        multi-statement-allow: true

/**
 * 配置多数据源
 * @author ysguo
 * @date 2018-03-21
 */
@Configuration
public class DynamicDataSourceConfig {

    @Bean
    @ConfigurationProperties("spring.datasource.druid.first")
    public DataSource firstDataSource(){
        return DruidDataSourceBuilder.create().build();
    }

    @Bean
    @ConfigurationProperties("spring.datasource.druid.second")
    public DataSource secondDataSource(){
        return DruidDataSourceBuilder.create().build();
    }

    @Bean
    @Primary
    public DynamicDataSource dataSource(DataSource firstDataSource, DataSource secondDataSource) {
        Map<String, DataSource> targetDataSources = new HashMap<>();
        targetDataSources.put(DataSourceNames.FIRST, firstDataSource);
        targetDataSources.put(DataSourceNames.SECOND, secondDataSource);
        return new DynamicDataSource(firstDataSource, targetDataSources);
    }
}

/**
 * 动态数据源
 * @author ysguo
 * @date 2018-03-21
 */
public class DynamicDataSource extends AbstractRoutingDataSource {
    private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();

    public DynamicDataSource(DataSource defaultTargetDataSource, Map<String, DataSource> targetDataSources) {
        super.setDefaultTargetDataSource(defaultTargetDataSource);
        super.setTargetDataSources(new HashMap<>(targetDataSources));
        super.afterPropertiesSet();
    }

    @Override
    protected Object determineCurrentLookupKey() {
        return getDataSource();
    }

    public static void setDataSource(String dataSource) {
        contextHolder.set(dataSource);
    }

    public static String getDataSource() {
        return contextHolder.get();
    }

    public static void clearDataSource() {
        contextHolder.remove();
    }

}

/**
 * 增加多数据源，在此配置
 *
 * @author ysguo
 * @date 2018-03-21
 */
public interface DataSourceNames {
    String FIRST = "first";
    String SECOND = "second";

}

/**
 * 多数据源注解
 * @author ysguo
 * @date 2018-03-21
 */
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface DataSource {
    String name() default "";
}

/**
 * 多数据源，切面处理类
 * @author ysguo
 * 
 * @date 2018-03-21
 */
@Aspect
@Component
public class DataSourceAspect implements Ordered {
    protected Logger logger = LoggerFactory.getLogger(getClass());

    @Pointcut("@annotation(com.ysguo.datasources.annotation.DataSource)")
    public void dataSourcePointCut() {

    }

    @Around("dataSourcePointCut()")
    public Object around(ProceedingJoinPoint point) throws Throwable {
        MethodSignature signature = (MethodSignature) point.getSignature();
        Method method = signature.getMethod();

        DataSource ds = method.getAnnotation(DataSource.class);
        if(ds == null){
            DynamicDataSource.setDataSource(DataSourceNames.FIRST);
            logger.debug("set datasource is " + DataSourceNames.FIRST);
        }else {
            DynamicDataSource.setDataSource(ds.name());
            logger.debug("set datasource is " + ds.name());
        }

        try {
            return point.proceed();
        } finally {
            DynamicDataSource.clearDataSource();
            logger.debug("clean datasource");
        }
    }

    @Override
    public int getOrder() {
        return 1;
    }
}

在Service方法上使用@DataSource注解切换数据源

@Service
public class UserInfoServiceImpl implements UserInfoService {
    @Autowired
    private UserInfoMapper userInfoMapper;

    @Override
    @DataSource(name=DataSourceNames.SECOND)
    public List<User> getUserInfoById(Integer userId) {
        return this.userInfoMapper.getUserInfoById(userId);
    }
}