Use Nginx to add login verification to an existing Web site (without adding changes to existing site code)

Add validation functionality without changing existing site code: 1. Assuming the existing Web site backend Nodejs, the port 3000,nginx configuration is as follows

server {
        listen      ;
        server_name localhost;
        Location/{
            proxy_pass  http://localhost:3000;
        }
 

2. To add validation to the site now, you need to do the following without changing the original code:A. First you need to add the Http_auth_request module (attachment) for Nginx, and if Nginx version 1.5.4+ you do not need this module B. Create a new Node.js Express Web site, Port 3001, and add login verification features: C. Modify the Nginx configuration file as follows:

    server { 
            listen;
            server_name localhost;
            Location/{ 
                Auth_request/auth; 
                Proxy_pass http://localhost:3000; 
            } 
            location/auth{ 
                proxy_pass http://localhost:3001;
                Proxy_pass_request_body off; 
                Proxy_set_header content-length ""; 
                Proxy_set_header X-original-uri $request _uri; 
            } 
            location/login{ 
                proxy_pass http://localhost:3001;
            } 
            Error_page 403/login;
        }

principle: access to port 80, first sent by Auth_request to the/auth authentication request, if it is validated then return 200,nginx continue to send the request to 3000 port, if/auth return 403, Then Nginx will not send the request to Port 3000, and finally define the 403 location.