Null error from findByIdAndUpdate

Question

So I have this API method:

router.delete('/circleAlertDelete/:id', function(req, res, next){
  User.findOne({_id: req.params.id}).then(function(user){
    var userTemp = user;
    var alerts = user.circleAlerts;
    var i = 0;
    for(i=0; i<alerts.length; i++){
      if(alerts._id == req.body.alertID){
        alerts.splice(i,1);
      }
    }
    userTemp.circleAlerts = alerts;
    console.log(req.params.id);
    User.findByIdAndUpdate({'_id': req.params.id}, userTemp, function(err, user){
      console.log("error:",err);
      res.send(user);
    });
  }).catch((err) => console.error(err));
});

I've also tried this to no avail:

{'_id': mongo.ObjectId(req.params.id)}

When run the id printed with console.log(req.params.id);is that of a user in the database.

But also printed is error: null.

Can't figure this out, Thanks Ed.

It goes through but it can't find the user and therefore doesn't update it. — Ed Lynch, Aug 06 '17 at 20:27
You are not surrounding the `console.log('error:', err)` with an `if(err)` statement. That way, the error line is printed always. Even when there is no error. — David, Aug 06 '17 at 20:39

score 1 · Accepted Answer · answered Aug 06 '17 at 20:34

Try passing plain object with just the field you want to set to findByIdAndUpdate:

User.findByIdAndUpdate(req.params.id, {circleAlerts: alerts}, function(err, user) {

Which effectively is turned into the following update operation:

$set: { circleAlerts: alerts }}

score -1 · Answer 2 · answered Aug 06 '17 at 20:34

-1

You are not specifying how to update the document, just passing the new object. Try with

User.findByIdAndUpdate({_id: req.params.id}, {$set: userTemp}, function(err, user){
   console.log("error:",err);
   res.send(user);
});

answered Aug 06 '17 at 20:34

Dario

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I think you would need to call `userTemp.toObject()`. Note also that this updates all fields in user document, not just `circleAlerts`. – jsalonen Aug 06 '17 at 20:36

Null error from findByIdAndUpdate

2 Answers2