Feign透传Header

@Configuration(proxyBeanMethods = false)
public class FeignConfig implements RequestInterceptor {

    @Override
    public void apply(RequestTemplate requestTemplate) {
        ServletRequestAttributes attributes = (ServletRequestAttributes)
                RequestContextHolder.getRequestAttributes();
        if (attributes != null) {
            HttpServletRequest request = attributes.getRequest();
            Enumeration<String> headerNames = request.getHeaderNames();
            if (headerNames != null) {
                while (headerNames.hasMoreElements()) {
                    String name = headerNames.nextElement();
                    String values = request.getHeader(name);
                    // 跳过 content-length
                    //feign.Client.Default.convertAndSend line 173，feign中修正该字段的时候是根据Util.CONTENT_LENGTH匹配的
                    if (Util.CONTENT_LENGTH.equalsIgnoreCase(name)) {
                        continue;
                    }
                    requestTemplate.header(name, values);
                }
            }
        }

    }
}
```