Express.js：发布时获取用户的referer url

Question

So I want to create a commenting system for my website, and in order to know the page of the comment (for example, a specific video a user has uploaded), I somehow need to get the url of the page the user is currently on, when they comment (so that I know how to save it in the database).

The route is like this: app.get('/video/:videoId', function(req, res){...}) so a video url would be something like: /video/98ux8987s987f9xc89v3wjgrkgh32 .

I need to get the last part of the url, when the user POSTs the comment. I don't want to send the url along with the comment (in the ajax POST function), because they can change it!

And by the way I don't need the url post url (if I have something like req.url in the post function, I'll just get the post url: app.post('/comment', function(req, res){console.log(req.url)} if I do this I'll get /comment ).

Is there a way to do it ?

Thank you very much.

Answer 1

I'm not sure if I get you, but is this what you mean?

app.post('/comment/:videoId', function(req, res) {
    console.log(req.params.videoId)
}

The videoId parameter is in req.params.videoId.

Answer 2

You can add hash with url, but it's not unstoppable . In the videoKey you can add the date or user id.

var secretkey = "4658{=#mkZl"; // The user doesn't know this string, and he can't make videoKey.

app.get('/video/:videoId', function(req, res){    
    res.render('video', {
        videoId: req.params.videoId,
        videoKey: sha256(secretkey + req.params.videoId + secretkey);
    });
};

In your html form :

<form action="/comment">
    <input type="hidden" name="videoId" value="{videoId}" />
    <input type="hidden" name="videoKey" value="{videoKey}" />
</form>

comment function :

var secretkey = "4658{=#mkZl";

app.post('/comment', function(req, res){
    if (req.body.videoKey == sha256(secretkey + req.body.videoId + secretkey))
        //ok the user got video page, before he comments.
};

sha256 function :

var crypto = require('crypto');

function sha256(data) {
    return crypto.createHash("sha256").update(data).digest("base64");
}