redis限制请求频率及资源隔离
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背景
由于导入及导出服务的使用，可能过多占用业务系统的请求。
为此在db层次做了切分（资源隔离）使用不同的db连接池。
同时针对导入导出服务增加请求频率限制，避免占用过多资源
解决方案
db连接资源分离
比较简单的利用spring做dataSource路由
/**
* Created by qixiaobo on 2016/12/2.
*/
public class DataSourceRouter extends AbstractRoutingDataSource {
@Override
protected Object determineCurrentLookupKey() {
return WxbStatic.getDataSourceRouting();
}
}
import com.air.tqb.annoate.DataSource;import com.air.tqb.annoate.DataSourceType;import com.air.tqb.utils.WxbStatic;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.aspectj.lang.ProceedingJoinPoint;import org.aspectj.lang.annotation.Around;import org.aspectj.lang.annotation.Aspect;import org.springframework.core.Ordered;import org.springframework.core.annotation.Order;import org.springframework.stereotype.Component;
/**
* Created by qixiaobo on 2016/12/2.
*/@Aspect@Component@Order(Ordered.HIGHEST_PRECEDENCE + 2)public class DataSourceRoutingAspect {
private static final Log logger = LogFactory.getLog(DataSourceRoutingAspect.class);
@Around("execution(public * com.air.tqb.service..*.*(..)) && @annotation(com.air.tqb.annoate.DataSource) && @annotation(dataSource)")
public Object setDataSource(ProceedingJoinPoint joinPoint, DataSource dataSource) throws Throwable {
DataSourceType dataSourceType = dataSource.value();
try {
WxbStatic.setDataSourceRouting(dataSourceType.getValue());
if (logger.isDebugEnabled()) {
logger.debug("DataSourceType[" + dataSourceType.getValue() + "] set.");
}
return joinPoint.proceed();
} finally {
WxbStatic.clearDataSourceRouting();
if (logger.isDebugEnabled()) {
logger.debug("DataSourceType[" + dataSourceType.getValue() + "] remove.");
}
}
}
@Around("execution(public * com.air.tqb.service.report..*.*(..))")
public Object setDataSource(ProceedingJoinPoint joinPoint) throws Throwable {
DataSourceType dataSourceType = DataSourceType.SLOW;
try {
WxbStatic.setDataSourceRouting(dataSourceType.getValue());
if (logger.isDebugEnabled()) {
logger.debug("report DataSourceType[" + dataSourceType.getValue() + "] set.");
}
return joinPoint.proceed();
} finally {
WxbStatic.clearDataSourceRouting();
if (logger.isDebugEnabled()) {
logger.debug("report DataSourceType[" + dataSourceType.getValue() + "] remove.");
}
}
}
}
这样我们可以吧report和正常请求区分开来。使用不同的db连接
/**
* Created by qixiaobo on 2016/12/2.
*/@Target({ElementType.METHOD})@Retention(RetentionPolicy.RUNTIME)@Inherited
public @interface DataSource {
DataSourceType value() default DataSourceType.NORMAL;
}
package com.air.tqb.annoate;
public enum DataSourceType {
NORMAL("normal"), SLOW("slow"), REPORT("report");
DataSourceType(String value) {
this.value = value;
}
private String value;
public String getValue() {
return value;
}
}
在不同的方法上加上指定的db标签可以完成db的选择。从而完成资源隔离。
方法调用限制
对于指定的占用资源方法采用开发按照key做配置，对于指定次数的限制
@Target({ElementType.METHOD})@Retention(RetentionPolicy.RUNTIME)@Inheritedpublic @interface OperationLimit {
int value() default 5;
String key() default "import";
}
package com.air.tqb.aop;
import com.air.tqb.Exception.LimitOperationException;import com.air.tqb.annoate.OperationLimit;import com.google.common.base.Throwables;import org.aspectj.lang.ProceedingJoinPoint;import org.aspectj.lang.annotation.Around;import org.aspectj.lang.annotation.Aspect;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.beans.factory.annotation.Qualifier;import org.springframework.core.Ordered;import org.springframework.core.annotation.Order;import org.springframework.data.redis.core.StringRedisTemplate;import org.springframework.data.redis.core.ValueOperations;import org.springframework.stereotype.Component;
import java.util.concurrent.TimeUnit;
@Aspect@Component@Order(Ordered.HIGHEST_PRECEDENCE + 4)public class OperationLimitAspect {
@Autowired
@Qualifier(value = "stringRedisTemplate")
private StringRedisTemplate template;
private final static String LIMIT_KEY_PREFIX = "limit:";
@Around("@annotation(com.air.tqb.annoate.OperationLimit) && @annotation(operationLimit)")
public Object operationLimit(ProceedingJoinPoint joinPoint, OperationLimit operationLimit) {
ValueOperations<STRING, string="">stringStringValueOperations = template.opsForValue();
final String key = getLimitKey(operationLimit);
Long incremented = stringStringValueOperations.increment(key, 1);
//暂时不考虑事务了，简单策略过期即可
stringStringValueOperations.getOperations().expire(key, 180, TimeUnit.SECONDS);
boolean limitReached = checkLimit(incremented, operationLimit);
if (limitReached) {
stringStringValueOperations.increment(key, -1);
throw new LimitOperationException("当前操作" + operationLimit.key() + "已经超过最大操作数" + operationLimit.value() + "限制，请稍后再试！");
} else {
try {
return joinPoint.proceed();
} catch (Throwable throwable) {
return Throwables.propagate(throwable);
} finally {
stringStringValueOperations.increment(key, -1);
}
}
}
private boolean checkLimit(Long incremented, OperationLimit operationLimit) {
if (operationLimit.value() < 0 || incremented <= operationLimit.value()) {
return false;
}
return true;
}
private String getLimitKey(OperationLimit operationLimit) {
return LIMIT_KEY_PREFIX + operationLimit.key();
}
}
来源：极客头条