Where does the var User come from in Passport documentation

Question

I am just getting my head round Passport in Node

 passport.use(new LocalStrategy(
   function(username, password, done) {
     User.findOne({ username: username }, function (err, user) {
       if (err) { return done(err); }
       if (!user) {
         return done(null, false, { message: 'Incorrect username.' });
       }
       if (!user.validPassword(password)) {
         return done(null, false, { message: 'Incorrect password.' });
       }
       return done(null, user);
     });
   }
 ));

This is all great, I understand the logic. However I don't understand where variables User from

User.findOne({ username:....

Is coming from? This isn't set anywhere and baffles me a little.

Without knowing the library, just pointing out Node.JS has a `global` global object that is treated as the [root](http://stackoverflow.com/questions/21578446/what-is-the-root-object-in-node-js) object. Some libraries like to break (what's arguably widely accepted as) the module paradigm and convention, adding things like what you're describing to this `global` or `root` object in order to be accessible by all scripts, regardless of whether or not they've `require`d the containing script. — Qix - MONICA WAS MISTREATED, Oct 04 '14 at 21:33

score 2 · Accepted Answer · edited Oct 04 '14 at 21:28

2

The example is using a mongoose model (User) that was defined elsewhere. Mongoose models have a findOne function. It's meant to mostly be filler to show how you would use the strategy to lookup info in the db to authenticate the user.

edited Oct 04 '14 at 21:28

mscdex

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answered Oct 04 '14 at 21:22

Lbatson

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arghhh... Good lord :) Learning to use Node and things like passport reminds me of using facebook's api when it first came out, or phonegap. In fact, just anything that is poorly documented :) – Jamie Hutber Oct 04 '14 at 21:25
2

yea, the whole assumption of using a specific db or implementation is sort of annoying and you'll find this in many examples. Some do a better job of explaining it though. maybe open up an issue for passport.js to update that to help others avoid the confusion :) – Lbatson Oct 04 '14 at 21:28
1

Ye, i agree. Either way very helpful. Until that time maybe people will find here – Jamie Hutber Oct 05 '14 at 21:05

Where does the var User come from in Passport documentation

1 Answers1