node.js - Mongoose findOneAndUpdate and runValidators not working

Question

I am having issues trying to get the 'runValidators' option to work. My user schema has an email field that has required set to true but each time a new user gets added to the database (using the 'upsert' option) and the email field is empty it does not complain:

 var userSchema = new mongoose.Schema({
   facebookId: {type: Number, required: true},
   activated: {type: Boolean, required: true, default: false},
   email: {type: String, required: true}
});

findOneAndUpdate code:

model.user.user.findOneAndUpdate(
      {facebookId: request.params.facebookId},
      {
          $setOnInsert: {
              facebookId: request.params.facebookId,
              email: request.payload.email,
          }
      },
      {upsert: true, 
       new: true, 
       runValidators: true, 
       setDefaultsOnInsert: true
      }, function (err, user) {
          if (err) {
              console.log(err);
              return reply(boom.badRequest(authError));
          }
          return reply(user);
      });

I have no idea what I am doing wrong, I just followed the docs: http://mongoosejs.com/docs/validation.html

In the docs is says the following:

Note that in mongoose 4.x, update validators only run on $set and $unset operations. For instance, the below update will succeed, regardless of the value of number.

I replaced the $setOnInsert with $set but had the same result.

Answer 1

required validators only fail when you try to explicitly $unset the key.

This makes no sense to me but it's what the docs say.