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JavaScript User Authentication With Express and Mongo Sessions and Cookies Creating the Profile Route and Page

Posted by Jason Pallone
Jason Pallone
11,340 Points

Where does user come from?

in the video, we use user, i know User is our schema, but this is the lowercase u user, where does it get defined and how?

Thanks!

2 Answers

Kevin D
Kevin D
8,646 Points 
User.findById(req.session.userId)
  .exec(function (error, user) {
    if (error) {
      return next(error);
    } else {
      return res.render('profile', { title: 'Profile', name: user.name, favorite: user.favoriteBook });
    }
  });
  • The user part gets defined in function signature of the callback function:
    • .exec(function (error, user) {})
  • When the computer runs:
    • User.findById(req.session.userId)
  • If it finds the userId, it passes on the User data to the .exec callback function
  • You could call it whatever you wanted e.g. human for instance
    • .exec(function (error, human) {})
    • Then you could access the properties like this: human.name, human.favoriteBook

Further reading:

Jason Pallone
Jason Pallone
11,340 Points

So when using model.findOne() or .findbyId it will automatically pass it's value to the next .exec function, as the 2nd argument of that function?

Kevin D
Kevin D
8,646 Points

Yes, from looking at the docs/reference it looks like it will return the value (if found/successful) into the second parameter

Jason Pallone
Jason Pallone
11,340 Points
Jason Pallone
Jason Pallone
11,340 Points

Ok that makes sense, thanks for the help!