springCloud 使用feign复制请求头调用其他服务 content-length不一致导致调用失败

背景：目前需要前端需要从B系统中获取数据，请求先发送到A系统，然后由A系统使用Feign调用B系统的接口，由于调用B系统时需要将请求的用户相关信息一起带到B系统，所以是用的Feign的请求拦截对其进行请求头复制

以下是请求头复制的拦截器

package cn.rivamed.hvc.filter;

import feign.RequestInterceptor;
import feign.RequestTemplate;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.util.Enumeration;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 * 描述: TODO
 * 公司 北京瑞华康源科技有限公司
 * 版本 rivamed2019
 *
 * @version V2.0.1
 * @author: 左健宏
 * @date: 2019-12-20 13:08
 */
@Configuration
public class FeginInterceptor implements RequestInterceptor {
    @Override
    public void apply(RequestTemplate requestTemplate) {
        try {
            Map<String,String> headers = getHeaders();
            for(String headerName : headers.keySet()){
                requestTemplate.header(headerName, headers.get(headerName));
            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }
    private Map<String, String> getHeaders(){
        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
        Map<String, String> map = new LinkedHashMap<>();
        Enumeration<String> enumeration = request.getHeaderNames();
        while (enumeration.hasMoreElements()) {
            String key = enumeration.nextElement();
            String value = request.getHeader(key);
//            if ("content-length".equals(key)) {
//                continue;
//            }
            map.put(key, value);
        }
        return map;
    }

}

该拦截器复制了所有请求头，包括content-length（重点），最初浮现的问题是

 在postMan写入的json不规范导致请求B系统报错

org.springframework.http.converter.HttpMessageNotReadableException: I/O error while reading input message; nested exception is org.apache.catalina.connector.ClientAbortException: java.io.EOFException: Unexpected EOF read on the socket

如果规范就没问题

 经过多次踩坑才知道特喵的 content-length是由body里面字符数控制的

所以问题明了了，贴上解决后的拦截器

package cn.rivamed.hvc.filter;

import feign.RequestInterceptor;
import feign.RequestTemplate;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.util.Enumeration;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 * 描述: TODO
 * 公司 北京瑞华康源科技有限公司
 * 版本 rivamed2019
 *
 * @version V2.0.1
 * @author: 左健宏
 * @date: 2019-12-20 13:08
 */
@Configuration
public class FeginInterceptor implements RequestInterceptor {
    @Override
    public void apply(RequestTemplate requestTemplate) {
        try {
            Map<String,String> headers = getHeaders();
            for(String headerName : headers.keySet()){
                requestTemplate.header(headerName, headers.get(headerName));
            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }
    private Map<String, String> getHeaders(){
        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
        Map<String, String> map = new LinkedHashMap<>();
        Enumeration<String> enumeration = request.getHeaderNames();
        while (enumeration.hasMoreElements()) {
            String key = enumeration.nextElement();
            String value = request.getHeader(key);
            if ("content-length".equals(key)) {
                continue;
            }
            map.put(key, value);
        }
        return map;
    }

}

content-length详解参考文章 ：https://juejin.im/post/5d772cb4e51d453b5f1a0502