Mongoengine creation_time attribute in Document

Question

I am trying to add a creation_time attribute to my documents. The following would be an example:

import datetime

class MyModel(mongoengine.Docu         


        

Answer 1

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.

Answer 2

If you are using the timestamp field in a bunch of Documents you can keep your code DRY by creating an abstract Document instead.

from datetime import datetime
from mongoengine import Document

class CreateUpdateDocument(Document):
    meta = {
        'abstract': True
    }

    # last updated timestamp
    updated_at = DateTimeField(default=datetime.now)

    # timestamp of when entry was created
    created_at = DateTimeField(default=datetime.now)

    def save(self, *args, **kwargs):
        if not self.created_at:
            self.created_at = datetime.now()
        self.updated_at = datetime.now()
        return super(CreateUpdateDocument, self).save(*args, **kwargs)

Answer 3

You could use auto_now_add parameter as per documentation:

class MyModel(mongoengine.Document):
    creation_date = mongo.DateTimeField(auto_now_add = True)
    modified_date = mongo.DateTimeField(auto_now = True)