当我们使用 nginx 代理转发服务后，会发现我们无法获取客户端的真实ip地址，从而无法获取客户端的地理位置等信息。

1、原始配置文件如下

worker_processes  1;

events {
    worker_connections  1024;
}

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

    sendfile        on;
    
    keepalive_timeout  65;

    server {
        listen       80;
        server_name  localhost;

        location / {
            root   html;
            index  index.html index.htm;
        }

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

}

2、配置转发后

worker_processes  1;

events {
    worker_connections  1024;
}

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

    sendfile        on;
    
    keepalive_timeout  65;

    server {
        listen       80;
        server_name  localhost;

        location / {
            root   html;
            index  index.html index.htm;
        }
        
        # 代理转发
        location /api/{
            proxy_set_header Host $http_host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header REMOTE-HOST $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header Public-Network-URL http://$http_host$request_uri;
            proxy_pass http://localhost:8080/;
        }
        
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }
    }

}

这样，我们就将客户端的头部信息一起转发过去，就能获取用户的真实 IP 地址了。