spring cloud gateway 之zuul通過filter配置接口請求的時間耗時記錄到日志

zuul中的Filter的配置,zuul中提供了三種類型的Filter,preFilter,routeFilter和postFilter,分別對應請求中的不同的階段,針對同一個請求,有一個RequestContext對象,在三個階段的Filter中進行共享

假設我們要開發一個統計請求時間的功能,需要在preFilter里邊記錄開始時間,並將整個開始時間放在RequestContext中,在postFilter里邊拿到開始時間,用當前的時間減去開始時間,就是請求執行的時間

定義一個preFilter:

package com.jiaoyiping.springcloud.zuul.filter;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cloud.netflix.zuul.filters.support.FilterConstants;

/**
 * Created with Intellij IDEA
 *
 * @author: 
 * Mail: 
 * Date: 
 * Time: 
 * To change this template use File | Settings | Editor | File and Code Templates
 */

public class TimeCostPreFilter extends ZuulFilter {
    public static final String START_TIME_KEY = "start_time";
    private Logger logger = LoggerFactory.getLogger(TimeCostPreFilter.class);

    @Override
    public String filterType() {
        return FilterConstants.PRE_TYPE;
    }

    @Override
    public int filterOrder() {
        return 0;
    }

    /**
     * 判斷是否要攔截的邏輯
     *
     * @return
     */
    @Override
    public boolean shouldFilter() {
        return true;
    }

    @Override
    public Object run() throws ZuulException {
        long startTime = System.currentTimeMillis();
        RequestContext.getCurrentContext().set(START_TIME_KEY, startTime);
        return null;
    }
}

定義以postFilter:

package com.jiaoyiping.springcloud.zuul.filter;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.cloud.netflix.zuul.filters.support.FilterConstants;

/**
 * Created with Intellij IDEA
 *
 * @author: 
 * Mail: 
 * Date: 
 * Time: 
 * To change this template use File | Settings | Editor | File and Code Templates
 */

public class TimeCostPostFilter extends ZuulFilter {
    private static final String START_TIME_KE = "start_time";
    private Logger logger = LoggerFactory.getLogger(TimeCostPostFilter.class);

    @Override
    public String filterType() {
        return FilterConstants.POST_TYPE;
    }

    @Override
    public int filterOrder() {
        return 0;
    }

    @Override
    public boolean shouldFilter() {
        return true;
    }

    @Override
    public Object run() throws ZuulException {
        long startTime = (long) RequestContext.getCurrentContext().get(START_TIME_KE);
        logger.info("請求完成,耗時{}秒", (System.currentTimeMillis() - startTime) / 1000);
        return null;
    }
}

在一個配置類中將這兩個Filter注入:

package com.jiaoyiping.springcloud.zuul.config;

import com.jiaoyiping.springcloud.zuul.filter.PDSFilter;
import com.jiaoyiping.springcloud.zuul.filter.TimeCostPostFilter;
import com.jiaoyiping.springcloud.zuul.filter.TimeCostPreFilter;
import com.netflix.zuul.ZuulFilter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * Created with Intellij IDEA
 *
 * @author: 
 * Mail: 
 * Date: 
 * Time:
 * To change this template use File | Settings | Editor | File and Code Templates
 */
@Configuration
public class FilterConfig {

    @Bean
    public ZuulFilter timeCostPreFilter() {
        return new TimeCostPreFilter();
    }

    @Bean
    public ZuulFilter timeCostPostFilter() {
        return new TimeCostPostFilter();
    }


    @Bean
    public ZuulFilter pdsFilter() {
        return new PDSFilter();
    }
}

啟動項目,可以發現,zuul網關已經注冊到了eureka上:

請求provide對應的地址,發現,zuul可以成功地調用eureka上對應的服務,並將結果正確返回: