(十四)java版spring cloud微服務架構b2b2c電子商務平臺-Hystrix項目中使用

一、公共類、不是必須的

package com.xxx.xxx.xxx.data.command.dubbo;

import com.netflix.hystrix.*;

public abstract class AbstractDubboCommand<T> extends HystrixCommand<T> {

    /**
     * @param commandKey
     */
    public AbstractDubboCommand(String commandKey) {
        super(DubboCommandSetter.setter(commandKey));
    }

    @Override
    public T getFallback(){
        //判斷熔斷器是否打開
        if(super.isCircuitBreakerOpen()){
            alert();
        }
        return fallback();
    }

    /**
     * 當熔斷器打開時，報警。報警間隔時間爲5分鐘
     */
    public abstract void alert();

    /**
     * 降級處理
     * @return
     */
    public abstract T fallback();

    public boolean needCache(){
        return false;
    }
}

熔斷器的設置

package com.xxx.xxx.xxx.data.command.dubbo;

import com.netflix.hystrix.HystrixCommand;
import com.netflix.hystrix.HystrixCommand.Setter;
import com.netflix.hystrix.HystrixCommandGroupKey;
import com.netflix.hystrix.HystrixCommandKey;
import com.netflix.hystrix.HystrixCommandProperties;
import com.netflix.hystrix.HystrixThreadPoolKey;
import com.netflix.hystrix.HystrixThreadPoolProperties;
/**
 * Comand公共參數的設置
 *
 * @author liweihan
 * @time 2017-12-20 16:53
 */
public class DubboCommandSetter {

    public static Setter setter(String commandKeyName,String threadPoolKeyName) {
        return setter("DubboGroup",commandKeyName,threadPoolKeyName);
    }

    public static Setter setter(String commandKeyName) {
        return setter(commandKeyName,"Dubbo-Pool");
    }

    /**
     * @author liweihan
     * @time 2017/12/20 16:57
     * @description     相關參數設置
     * @param groupKeyName      服務分組名
     * @param commandKeyName    服務標識名稱
     * @param threadPoolKeyName 線程池名稱
     * @return
     */
    public static Setter setter(String groupKeyName,String commandKeyName,String threadPoolKeyName) {
        //服務分組
        HystrixCommandGroupKey groupKey = HystrixCommandGroupKey.Factory.asKey(groupKeyName);
        //服務標識
        HystrixCommandKey commandKey = HystrixCommandKey.Factory.asKey(commandKeyName);
        //線程池名稱
        HystrixThreadPoolKey threadPoolKey = HystrixThreadPoolKey.Factory.asKey(threadPoolKeyName);
        //線程配置
        HystrixThreadPoolProperties.Setter threadPoolProperties = HystrixThreadPoolProperties.Setter()
                .withCoreSize(150)
                .withKeepAliveTimeMinutes(5)
                .withMaxQueueSize(Integer.MAX_VALUE)
                .withQueueSizeRejectionThreshold(10000)
                ;

        //命令屬性的配置
        HystrixCommandProperties.Setter commandProperties = HystrixCommandProperties.Setter()
                .withExecutionIsolationStrategy(HystrixCommandProperties.ExecutionIsolationStrategy.THREAD)
//                .withExecutionIsolationThreadInterruptOnTimeout(true)
                .withExecutionTimeoutInMilliseconds(3000) //設置超時時間爲3秒進入Fallback
                .withCircuitBreakerErrorThresholdPercentage(30)//失敗率達到30%自動熔斷
                .withRequestCacheEnabled(false);

        //返回
        return HystrixCommand.Setter
                .withGroupKey(groupKey)
				.andCommandKey(commandKey)
                .andThreadPoolKey(threadPoolKey)
                .andThreadPoolPropertiesDefaults(threadPoolProperties)
                .andCommandPropertiesDefaults(commandProperties);
    }

}

獲得基礎信息-Album的Command類

package com.xxx.xxx.xxx.data.command.dubbo;

import com.xxx.xxx.xxx.service.ServiceManager;
import com.xxx.xxx.xxx.util.CommonUtil;
import com.xxx.xxx.xxx.util.SerializationUtil;
import com.xxx.xxx.xxx.util.WxSmsUtils;
import com.xxx.xxx.xxx.midware.dubbo.api.dto.AlbumInfoDto;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author liweihan
 * @time 2017/10/12 15:12
 * @description 獲取PGC/UGC專輯基礎信息！
 */
public class GetAlbumInfoByDubboCommand extends AbstractDubboCommand<AlbumInfoDto> {
    public static final Logger logger = LoggerFactory.getLogger(GetAlbumInfoByDubboCommand.class);
    Long aid;
    ServiceManager serviceManager;

    public GetAlbumInfoByDubboCommand(Long aid , ServiceManager serviceManager) {
        super("GetAlbumInfo");
        this.aid = aid;
        this.serviceManager=serviceManager;
    }
    @Override
    public AlbumInfoDto fallback() {
        String key = String.format(CommonUtil.Get_AlbumInfo_ByDubbo, aid);
        logger.info(" GetAlbumInfoByDubboCommand from dubbo fail,key:{}",key);
        byte[] obj =  serviceManager.getRedisClusterHyStrix().getBytes(key);
        try {
            AlbumInfoDto albumInfoDto =  (AlbumInfoDto)SerializationUtil.bytes2Object(obj);
            return albumInfoDto;
        }catch  (Exception e) {
            logger.error(" ====== GetAlbumInfoByDubboCommand from Hystrix'fallback error,key:{} . Exception:{}" ,key,e);
        }
        return null;
    }

    @Override
    protected AlbumInfoDto run() throws Exception {
        AlbumInfoDto albumInfoDto = null;
        long beginTime = System.currentTimeMillis();
        try {
            /**
             * http://mwiki.sohuno.com/pages/viewpage.action?pageId=32866496
             */
            albumInfoDto = serviceManager.getDubboAlbumService().albumInfo(aid,0,"","17");
        } catch (Exception e) {
            logger.error(" ====== GetAlbumInfoByDubboCommand ,調用dubbo出錯！aid:{}",aid,e);
        }
        //統計一下該dubbo的訪問次數
//        incr("dubbo_album");
        long endTime  = System.currentTimeMillis();
        if ((endTime - beginTime) > CommonUtil.TIME_OUT_DUBBO) {
            //統計一下該dubbo超時的訪問次數
//            incr("dubbo_album_timeout");
            logger.warn(" ====== GetAlbumInfoByDubboCommand ,調用dubbo時間久！beginTime:{},endTime:{},cosTime:{},dubbo返回:{},aid:{}",
                    beginTime,endTime,(endTime-beginTime),albumInfoDto != null ? albumInfoDto.getReturnCode() : "null",aid);
        }
        if (albumInfoDto == null) {
            return fallback();
        }
        String key = String.format(CommonUtil.Get_AlbumInfo_ByDubbo, aid);
        if (albumInfoDto.getReturnCode() == 0) {
            serviceManager.getRedisClusterHyStrix().setex(key, CommonUtil.timeout, SerializationUtil.object2Bytes(albumInfoDto));
        } else {
            logger.info(" ====== GetAlbumInfoByDubboCommand,獲取專輯信息時,dubbo返回:{},aid:{}",albumInfoDto.getReturnCode(),aid);
            serviceManager.getRedisClusterHyStrix().del(key); //不等於0說明專輯失效或刪除，需要刪除hystrix的緩存
        }
        return albumInfoDto;
    }

    @Override
    public void alert() {
        logger.error(" ================================================== GetAlbumInfoByDubboCommand into CircuitBreaker");
        String key = "AlbumInfo";
        if (StringUtils.isEmpty(serviceManager.getRedisClusterHyStrix().get(key))) {
            WxSmsUtils.getInstance().warnByWx("AlbumInfo-Into-[CircuitBreaker]");
            serviceManager.getRedisClusterHyStrix().setex(key,CommonUtil.WARN_WX_TIMEOUT,key);
        }
    }

    /**
     * @author liweihan
     * @time 2017/11/13 17:12
     * @description     統計一下某個dubbo方法的次數
     * @param key
     */
    public void incr(String key) {
        try {
            serviceManager.getRedisCluster().incr(key);
        } catch (Exception e) {
            logger.error(" ====== redis操作出現異常！key:{}",key,e);
        }
    }
}

獲得基礎信息-UserInfo的Command類

package com.xxx.xxx.xxx.data.command.dubbo;

import com.xxx.xxx.xxx.service.ServiceManager;
import com.xxx.xxx.xxx.util.CommonUtil;
import com.xxx.xxx.xxx.util.SerializationUtil;
import com.xxx.xxx.xxx.util.WxSmsUtils;
import com.xxx.xxx.xxx.midware.dubbo.api.dto.UserInfoDto;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author liweihan
 * @time 2017/10/11 15:12
 * @description 獲取PGC/UGC用戶基礎信息！
 */
public class GetUserInfoByDubboCommand extends AbstractDubboCommand<UserInfoDto> {
    public static final Logger logger = LoggerFactory.getLogger(GetUserInfoByDubboCommand.class);
    Long userId;
    ServiceManager serviceManager;

    public GetUserInfoByDubboCommand(Long userId , ServiceManager serviceManager) {
        super("GetUserInfo");
        this.userId = userId;
        this.serviceManager=serviceManager;
    }
    @Override
    public UserInfoDto fallback() {
        String key = String.format(CommonUtil.Get_UserInfo_ByDubbo, userId);
        logger.info(" GetUserInfoByDubboCommand from dubbo fail,key:{}",key);
        byte[] obj =  serviceManager.getRedisClusterHyStrix().getBytes(key);
        try {
            UserInfoDto userInfoDto =  (UserInfoDto)SerializationUtil.bytes2Object(obj);
            return userInfoDto;
        }catch  (Exception e) {
            logger.error(" ====== GetUserInfoByDubboCommand from Hystrix'fallback error,key:{} . Exception:{}" ,key,e);
        }
        return null;
    }

    @Override
    protected UserInfoDto run() throws Exception {
        UserInfoDto userInfoDto = null;
        long beginTime = System.currentTimeMillis();
        try {
            /**
             * http://mwiki.sohuno.com/pages/viewpage.action?pageId=32866496
             */
            userInfoDto = serviceManager.getDubboUserService().userInfo(userId);
        } catch (Exception e) {
            logger.error(" ====== GetUserInfoByDubboCommand ,調用dubbo出錯！userId:{}",userId,e);
        }
        //統計一下該dubbo的訪問次數
//        incr("dubbo_userinfo");
        long endTime = System.currentTimeMillis();
        if ((endTime - beginTime) > CommonUtil.TIME_OUT_DUBBO_300) {
            //統計一下該dubbo的訪問次數
//            incr("dubbo_userinfo_timeout");
            logger.warn(" ====== GetUserInfoByDubboCommand ,調用dubbo時間久！beginTime:{},endTime:{},cosTime:{},dubbo返回:{},userId:{}",
                    beginTime,endTime,(endTime-beginTime),userInfoDto != null ? userInfoDto.getReturnCode() : "null",userId);
        }
        if (userInfoDto == null) {
            return fallback();
        }
        String key = String.format(CommonUtil.Get_UserInfo_ByDubbo, userId);
        if (userInfoDto.getReturnCode() == 0) {
            serviceManager.getRedisClusterHyStrix().setex(key, CommonUtil.timeout, SerializationUtil.object2Bytes(userInfoDto));
        } else {
            logger.info(" ====== GetUserInfoByDubboCommand,獲取用戶信息時,dubbo返回:{},userId:{}",userInfoDto.getReturnCode(),userId);
            serviceManager.getRedisClusterHyStrix().del(key);
        }
        return userInfoDto;
    }

    @Override
    public void alert() {
        logger.error(" ================================================== GetUserInfoByDubboCommand into CircuitBreaker");
        String key = "GetUserInfo";
        if (StringUtils.isEmpty(serviceManager.getRedisClusterHyStrix().get(key))) {
            WxSmsUtils.getInstance().warnByWx("GetUserInfo-Into-[CircuitBreaker]");
            serviceManager.getRedisClusterHyStrix().setex(key,CommonUtil.WARN_WX_TIMEOUT,key);
        }
    }

    /**
     * @author liweihan
     * @time 2017/11/13 17:12
     * @description     統計一下某個dubbo方法的次數
     * @param key
     */
    public void incr(String key) {
        try {
            serviceManager.getRedisCluster().incr(key);
        } catch (Exception e) {
            logger.error(" ====== redis操作出現異常！key:{}",key,e);
        }
    }
}

再其他的類也是類似的用法，你可以調用Http,RPC等第三方接口！寫法都是類似的。

此處熔斷後,進入Fallback讀取備用緩存數據，如果緩存沒有的話，再給用戶返回null。這是一種策略。