Nginx 直接输出IP地址，免端口

server {
	listen 80;
	listen [::]:80 ipv6only=on;
	server_name ip.larva.com.cn;

	location / {
		if ($request_method !~* GET|OPTIONS) {
			return 403;
		}
		if ($request_method = 'OPTIONS') {
			add_header 'Access-Control-Allow-Origin' '*';
			add_header 'Access-Control-Allow-Methods' 'GET, OPTIONS';
			#
			# Custom headers and headers various browsers *should* be OK with but aren't
			#

			add_header 'Access-Control-Allow-Headers' '*';
			#
			# Tell client that this pre-flight info is valid for 20 days
			#

			add_header 'Access-Control-Max-Age' 1728000;
			add_header 'Content-Type' 'text/plain; charset=utf-8';
			add_header 'Content-Length' 0;
			return 204;
		}
		if ($request_method = 'GET') {
			add_header 'Access-Control-Allow-Origin' '*';
			add_header 'Access-Control-Allow-Methods' 'GET, OPTIONS';
			add_header 'Access-Control-Allow-Headers' '*';
			add_header 'Access-Control-Expose-Headers' '*';
			add_header 'Content-Type' 'text/plain; charset=utf-8';
		}

		return 200 $remote_addr;
	}

	location /port {
		if ($request_method !~* GET|OPTIONS) {
			return 403;
		}
		if ($request_method = 'OPTIONS') {
			add_header 'Access-Control-Allow-Origin' '*';
			add_header 'Access-Control-Allow-Methods' 'GET, OPTIONS';
			#
			# Custom headers and headers various browsers *should* be OK with but aren't
			#

			add_header 'Access-Control-Allow-Headers' '*';
			#
			# Tell client that this pre-flight info is valid for 20 days
			#

			add_header 'Access-Control-Max-Age' 1728000;
			add_header 'Content-Type' 'text/plain; charset=utf-8';
			add_header 'Content-Length' 0;
			return 204;
		}
		if ($request_method = 'GET') {
			add_header 'Access-Control-Allow-Origin' '*';
			add_header 'Access-Control-Allow-Methods' 'GET, OPTIONS';
			add_header 'Access-Control-Allow-Headers' '*';
			add_header 'Access-Control-Expose-Headers' '*';
			add_header 'Content-Type' 'text/plain; charset=utf-8';
		}

		return 200 '$remote_addr:$remote_port';
	}

	location /json {
		if ($request_method !~* GET|OPTIONS) {
			return 403;
		}
		if ($request_method = 'OPTIONS') {
			add_header 'Access-Control-Allow-Origin' '*';
			add_header 'Access-Control-Allow-Methods' 'GET, OPTIONS';
			#
			# Custom headers and headers various browsers *should* be OK with but aren't
			#

			add_header 'Access-Control-Allow-Headers' '*';
			#
			# Tell client that this pre-flight info is valid for 20 days
			#

			add_header 'Access-Control-Max-Age' 1728000;
			add_header 'Content-Type' 'text/plain; charset=utf-8';
			add_header 'Content-Length' 0;
			return 204;
		}
		if ($request_method = 'GET') {
			add_header 'Access-Control-Allow-Origin' '*';
			add_header 'Access-Control-Allow-Methods' 'GET, OPTIONS';
			add_header 'Access-Control-Allow-Headers' '*';
			add_header 'Access-Control-Expose-Headers' '*';
			add_header 'Content-Type' 'application/json; charset=utf-8';
		}

		return 200 '{"ip":"$remote_addr","port":$remote_port}';
	}
}