我的代码是这样的，

params['host_url'] = req.protocol + '：//' + req.headers.host + req.url;

我建议使用originalUrl而不是URL:

var url = req.protocol + '://' + req.get('host') + req.originalUrl;

查看originalUrl的描述: http://expressjs.com/api.html#req.originalUrl

在我们的系统中，我们这样做，所以originalUrl对我们很重要:

  foo = express();
  express().use('/foo', foo);
  foo.use(require('/foo/blah_controller'));

Blah_controller是这样的:

  controller = express();
  module.exports = controller;
  controller.get('/bar/:barparam', function(req, res) { /* handler code */ });

我们的url有这样的格式

www.example.com/foo/bar/:barparam

因此，我们需要req。originalUrl在bar控制器的获取处理程序。

const fullUrl = `${protocol}://${host}:${port}${url}`
      
    const responseString = `Full URL is: ${fullUrl}`;                       
    res.send(responseString);  
})

我的代码是这样的，

params['host_url'] = req.protocol + '：//' + req.headers.host + req.url;

通常我依赖这2个，取决于服务器和代理是否存在:

req.socket.remoteAddress

req.headers.referer

使req.host /点播。当Express后台代理时，主机名有效必须满足两个条件:

App.set('信任代理'，'环回');在app.js x - forward - host头必须由你自己在webserver中指定。如。apache, nginx

nginx:

server {
    listen myhost:80;
    server_name  myhost;
    location / {
        root /path/to/myapp/public;
        proxy_set_header X-Forwarded-Host $host:$server_port;
        proxy_set_header X-Forwarded-Server $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_pass http://myapp:8080;
    }
}

apache:

<VirtualHost myhost:80>
    ServerName myhost
    DocumentRoot /path/to/myapp/public
    ProxyPass / http://myapp:8080/
    ProxyPassReverse / http://myapp:8080/
</VirtualHost>