我在nodejs / mongodb上的更新功能在做什么？

Question

Hi I am currently new to nodejs and mongodb what I want to do is make a function to update my win,lose,draw record from my userschema.

My Schema:

UserSchema = new mongoose.Schema({
    username:'string',
    password:'string',
    email:'string',
    //Change Made
    win:{ type: Number, default: 0 },
    lose:{ type: Number, default: 0 },
    draw:{ type: Number, default: 0 }
});

var db = mongoose.createConnection(app.get('MONGODB_CONN')),
    User = db.model('users', UserSchema);

My Function for updating:

app.post('/user/updateScores',function(req, res){
try{
      var query = req.body.username;
      User.findOneAndUpdate(query, { win : req.body.win, lose : req.body.lose, draw : req.body.draw }, function (err,user){
           if (err) res.json(err) ;
             req.session.loggedIn = true;
             res.redirect('/user/' + user.username);
      });
    }
    catch(e){
        console.log(e)
    }
  });

The problem is when I try updating, it updates the current data BUT goes to a blank page and throws an exception saying:

ReferenceError: win is not defined
    at eval (eval at <anonymous> (C:\Users\ryan-utb\Desktop\RockScissorsPaper\node_modules\underscore\underscore.js:1176:16), <anonymous>:5:9)
    at template (C:\Users\ryan-utb\Desktop\RockScissorsPaper\node_modules\underscore\underscore.js:1184:21)
    at Function.exports.underscore.render (C:\Users\ryan-utb\Desktop\RockScissorsPaper\node_modules\consolidate\lib\consolidate.js:410:14)
    at C:\Users\ryan-utb\Desktop\RockScissorsPaper\node_modules\consolidate\lib\consolidate.js:106:23
    at C:\Users\ryan-utb\Desktop\RockScissorsPaper\node_modules\consolidate\lib\consolidate.js:90:5
    at fs.js:266:14
    at Object.oncomplete (fs.js:107:15)

but I already defined win properly, what seems to be the problem?

Answer 1

User.update(
    {username:req.body.username},
    { win : req.body.win, lose : req.body.lose, draw : req.body.draw },
    function (err, data) { //look - no argument name "user" - just "data"
    //2 mistakes here that you should learn to never do
    //1. Don't ignore the `err` argument
    //2. Don't assume the query returns something. Check that data is not null.
    console.log(data);
    //The next line must be INSIDE this function in order to access "data"
    res.redirect('/user/' + data.username);
});     
//ACK don't try to access "data" (or "user") here. this is asynchronous code!
//this code executes EARLIER IN TIME than the User.update callback code

update after your snippet v2

• your find call is simply not matching any documents, so user is null
• FYI You can do a find and update at the same time with a single findOneAndUpdate operation

Answer 2

  User.update({
    username: req.body.username
  },{
    $set: {
        win : req.body.name,
        loose : req.body.loose
    }
  }, function(err, result) {
     if (err) {
       console.log(err);
   } else if (result === 0) {
      console.log("user is not updated");
   } else {
      console.log("user is updated");
   }
 });

I hope you can understand your issue and can update your User collection.