在前后端分离的大超流下，前端单独布局势必会产生请求跨域的情况，那么通过Nginx代理转发可以帮助我们解决这个问题；在特定接口的转发中往往会有设置自定义请求的场景存在，接下来我们来看一个最简单的请求头配置方式。我们先来说明一下配置项的作用和用法：1、proxy_set_header用于设定自定义请求头，例如：keyid：81dcfe44-0e3f-4161-a6e6-******c30fb8的请求头该怎么配置呢？

proxy_set_header keyid 81dcfe44-0e3f-4161-a6e6-******c30fb8; # 自己系统访问api网关的keyid

2、underscores_in_headers on;用于开启请求头key支持下划线'_'特殊符号，默认为off

underscores_in_headers on;

完成配置如下：

user  nginx;
worker_processes  1;

#error_log  /var/log/nginx/error.log warn;
#pid        /var/run/nginx.pid;


events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    #access_log  /var/log/nginx/access.log  main;

    sendfile        on;
    tcp_nopush     on;

    keepalive_timeout  65;

    gzip  on;

    underscores_in_headers on;    # 用于解决请求头中包含下划线'_'的key

    server {
      listen       8888;
      listen  [::]:8888;
      server_name  _;
      root   dist/;

      location / {
          try_files $uri /index.html;
      }
	  
	  # 配置接口代理
      location ^~ /fileCenter {
		 proxy_set_header keyid 81dcfe44-0e3f-4161-a6e6-******c30fb8; # 自定义请求头keyid
         proxy_pass https://apitest.i.sino****.com:8060;
		 rewrite "^/fileCenter/(.*)$" /$1 break;
		 
	  }

      # 配置接口代理
      # location ^~ /baidu {
      #     proxy_pass https://www.baidu.com;
      #     rewrite "^/baidu/(.*)$" /$1 break;
      # }

      error_page   500 502 503 504  /50x.html;
      location = /50x.html {
          root   /app;
      }

      
      location ~ /\.map {
         deny  all;
      }
  }
}