Mongoengine creation_time attribute in Document

You could override the save method.

class MyModel(mongoengine.Document):    creation_date = mongo.DateTimeField()    modified_date = mongo.DateTimeField(default=datetime.datetime.now)    def save(self, *args, **kwargs):        if not self.creation_date:            self.creation_date = datetime.datetime.now()        self.modified_date = datetime.datetime.now()        return super(MyModel, self).save(*args, **kwargs)

As an aside, the creation time is stamped into the _id attribute - if you do:

YourObject.id.generation_time

Will give you a datetime stamp.

One nice solution is reusing a single signal handler for multiple documents.

class User(Document):    # other fields...    created_at = DateTimeField(required=True, default=datetime.utcnow)    updated_at = DateTimeField(required=True)class Post(Document):    # other fields...    created_at = DateTimeField(required=True, default=datetime.utcnow)    updated_at = DateTimeField(required=True)def update_timestamp(sender, document, **kwargs):    document.updated_at = datetime.utcnow()signals.pre_save.connect(update_timestamp, sender=User)signals.pre_save.connect(update_timestamp, sender=Post)

Be careful to assign a callable and not a fixed-value as the default, for example default=datetime.utcnow without (). Some of the other answers on this page are incorrect and would cause created_at for new documents to always be set to the time your app was first loaded.

It's also always better to store UTC dates (datetime.utcnow instead of datetime.now) in your database.