Validate a Mongoose model and then upsert if valid

validate-and-upsert.js

mySchema.statics.validateAndUpsert = function (conditions, update, callback) {
    var updateModel = new this(update);
    updateModel.validate(function (err) {
        if (err) {
            callback(err);
        } else {
            this.findOneAndUpdate(conditions, update, { upsert: true}, callback);
        }
    }
};