@FeignClient微服务之间调用，feign对reques

服务之间需要传递参数、请求头等，可以通过 RequestTemplate 对象进行传递，代码如下：
1、配置 request 拦截器类

package com.xxx.feign;

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;

/**
 * <p>ClassName: FeignConfigure</p>
 * <p>Description: feign对request做拦截处理</p>
 * <p>Author: xxx</p>
 * <p>Date: xxx</p>
 */
@Configuration
public class FeignConfigure implements RequestInterceptor {

    /**
     * <p> 在此可以做request参数处理，例如添加头部参数等 </p>
     * @author: xxx
     * @date: xxx
     * @param requestTemplate :
    **/
    @Override
    public void apply(RequestTemplate requestTemplate) {
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder
                .getRequestAttributes();
        HttpServletRequest request = attributes.getRequest();
        Enumeration<String> headerNames = request.getHeaderNames();
        if (headerNames != null) {
            while (headerNames.hasMoreElements()) {
                String name = headerNames.nextElement();
                String value = request.getHeader(name);
                requestTemplate.header(name, value);
            }
        }
    }
}

2、配置好 RequestTemplate 拦截器之后，需要在 FeignClinent 接口类中引用拦截器：
@FeignClient(value = "xxx-service",configuration = FeignConfigure.class)

@FeignClient(value = "xxx-service",configuration = FeignConfigure.class)
// 示例通过网关调用，第一个"/xxx"是 xx-service 网关应用访问的根目录(即路由转发之前的断言匹配规则)
// 第二个"/xxx"是被调用服务方的 @RequestMapping 路径
@RequestMapping(value = {"/xxx/xxx"})
public interface VhclFeignClient {
    @GetMapping(value = "/getVchlInfoById")
    CommonResult<Vhcl> getVchlInfoById(@RequestParam("id") int id);

    @PostMapping("/uc/saveVchlInfo")
    CommonResult<Vhcl> saveVchlInfo(Vhcl vhcl);
}