Nginx直接返回Json

server {  
listen       80;  
server_name  www.abc.com;

	large_client_header_buffers 4 16k;
	client_max_body_size 300m;
	client_body_buffer_size 128k;
	proxy_connect_timeout 600;
	proxy_read_timeout 600;
	proxy_send_timeout 600;
	proxy_buffer_size 64k;
	proxy_buffers   4 32k;
	proxy_busy_buffers_size 64k;
	proxy_temp_file_write_size 64k;

	location / {  
		default_type application/json;
		add_header Content-Type 'text/html; charset=utf-8';
		return 200 '{"success":false,"messge":"请升级客户端"}';
	}  
}server {  
listen       80;  
server_name  www.