Mongoose.js find() inside a find()

Question

Is it possible to do a find inside a find on Node with Mongoose?

I'm letting a user change their email address, but I have to make sure the email hasn't been used by any other user before I save the new email.

I want to do this:

/*************************************************************
* MY_USER - PROFILE UPDATE
*************************************************************/
app.put('/api/myuser/info', auth, function(req, res) {
  serverLog.log(req, production, {});

  // User ID
  var myUserID = req.session.passport.user._id;

  if ( myUserID && validateID(myUserID) ) {

     User.findOne({
        _id: myUserID
     }, function(err, data) {
        if (err) throw err;

        if (data == null) {
           res.sendStatus(401);
           console.log(401);
        }
        // Data
        else {

           // Update Email
           if (req.body.email) {

              // Check valid email
              if ( validateEmail(req.body.email) ) {
                 console.log('validateEmail');

                 // Check Unique Email
                 User.findOne({
                    'local.user.info.email': email
                 }, function(err, user) {

                    if(err) return err;

                    if ( user ) {
                       // Email already in use
                       res.status(400).send('ERROR: Email Already in Use');
                       return;
                    }
                    console.log('uniqueEmail ' + true);
                    // Update email
                    user.local.user.info.email = req.body.email;
                 })

              }
              // Bad Email
              else {
                 res.status(400).send('ERROR: Not a propper Email');
                 return;
              }

           }

           // SAVE USER DATA               
           if ( info_sent ) {

              user.save(function(err, data) {
                 if (err) throw err;

                 res.setHeader('Content-Type', 'application/json');
                 res.status(200).send(JSON.stringify(data.local.user.info, null, 3));
                 return;
              });
           }
           // NO INFO WAS SENT
           else {
              res.status(400).send('ERROR: No information was sent.');
              return;
           }
        }
     });
  } 
  // Bad / No User ID
  else {
     res.sendStatus(401);
  }
});

I find the user, then check if email is in use How would one go about doing this?

Possible duplicate of [Mongoose & unique field](https://stackoverflow.com/questions/21971666/mongoose-unique-field) — Derek Brown, Oct 13 '17 at 01:01
This seems to be a duplicate: https://stackoverflow.com/questions/21971666/mongoose-unique-field — Derek Brown, Oct 13 '17 at 01:02
Also would take a look at: https://www.npmjs.com/package/mongoose-unique-validator — Derek Brown, Oct 13 '17 at 01:02
That code ^ does not work. Can't do a find inside a find asynchronously. — Rio Weber, Oct 13 '17 at 01:27

TGrif · Answer 1 · 2017-10-13T23:52:15.163

This doesn't work because you do not save your user in the callback function that checks if email already exists. Also consider using Promise to avoid callback hell

Anyway, you can do it like this:

// Check Unique Email
User.findOne({'local.user.info.email': email }, (err, user) => {
  if (err) throw err;
  if (user) {
    return res.status(400).send('ERROR: Email Already in Use');
  } else {  // SAVE USER DATA        
   if (info_sent) {
     user.save((err, data) => {
       if (err) throw err;
       res.setHeader('Content-Type', 'application/json');
       return res.status(200).send(JSON.stringify(data.local.user.info, null, 3));
      });
    } else {
      return res.status(400).send('ERROR: No information was sent.');
    }
 }

Mongoose.js find() inside a find()

1 Answers1