谢谢大家提供这些信息。这是非常烦人的。

把这个添加到你的代码中，你就再也不用考虑它了:

var app = express();

app.all("*", function (req, res, next) {  // runs on ALL requests
    req.fullUrl = req.protocol + '://' + req.get('host') + req.originalUrl
        next()
})

您还可以在那里执行或设置其他操作，例如将日志记录到控制台。

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

你可以结合req。协议,要求。主机名和req.originalUrl。请注意要求。主机名，而不是请求。Host或req.get(“Host”)，这是可行的，但更难阅读。

const completeUrl = `${req.protocol}://${req.hostname}${req.originalUrl}`;

async function (request, response, next) {
  const url = request.rawHeaders[9] + request.originalUrl;
  //or
  const url = request.headers.host + request.originalUrl;
}

var full_address = req.protocol + "://" + req.headers.host + req.originalUrl;

or

var full_address = req.protocol + "://" + req.headers.host + req.baseUrl;

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