Mongoose Find e Atualize Prop

var query = {'username': req.user.username};
req.newData.username = req.user.username;

MyModel.findOneAndUpdate(query, req.newData, {upsert: true}, function(err, doc) {
    if (err) return res.send(500, {error: err});
    return res.send('Succesfully saved.');
});
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