python - Django : RunTimeWarning : DateTimeField received a naive datetime while time zone support is active

Question

I am trying to test a cart creation based on django cart

But I have this error when I am trying to create the cart :

RunTimeWarning : DateTimeField received a naive datetime while time zone support is active

I did some research but I couldn't resolve my problem for datetime.datetime.now()

test_views.py in my tests directory :

from django.test import TestCase, Client, RequestFactory
import unittest
from django.contrib.auth.models import User, AnonymousUser
from front.models import Entreprise, Cart, CartItems
from decimal import Decimal
from front.cart import models
import datetime
import pytz
from pytz import all_timezones
from django.utils import timezone



def _create_cart_in_database(self, creationDate=datetime.datetime.now(), checkedOutDate=True):
    """
        Helper function so I don't repeat myself
    """
    cart = models.Cart()
    cart.creationDate = creationDate
    cart.checkedOutDate = False
    cart.save()
    return cart


def test_cart_creation(self):
    creationDate = datetime.datetime.now()
    cart = self._create_cart_in_database(creationDate)
    id = cart.id

    cart_from_database = models.Cart.objects.get(pk=id)
    self.assertEquals(cart, cart_from_database)

models.py :

class Cart(models.Model):
    creationDate = models.DateTimeField()

I also have USE_TZ = True in my settings.

I tried timezone.now() but still doesn't work :

def _create_cart_in_database(self, creationDate=timezone.now(), checkedOutDate=True):

def test_cart_creation(self):
    creationDate = timezone.now()

RunTimeWarning : DateTimeField Cart.creationDate received a naive datetime (2016-06-03 08:46:34.829000) while time zone support is active.

EDIT :

I have this error now and it seems an error format datetime ?

    updated = self._save_table(raw, cls, force_insert, force_update, using, upda
te_fields)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\ba
se.py", line 820, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\ba
se.py", line 859, in _do_insert
    using=using, raw=raw)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\ma
nager.py", line 122, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\qu
ery.py", line 1039, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\sq
l\compiler.py", line 1059, in execute_sql
    for sql, params in self.as_sql():
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\sq
l\compiler.py", line 1019, in as_sql
    for obj in self.query.objs
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\sq
l\compiler.py", line 958, in prepare_value
    value = field.get_db_prep_save(value, connection=self.connection)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\fi
elds\__init__.py", line 728, in get_db_prep_save
    prepared=False)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\fi
elds\__init__.py", line 1461, in get_db_prep_value
    value = self.get_prep_value(value)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\fi
elds\__init__.py", line 1440, in get_prep_value
    value = super(DateTimeField, self).get_prep_value(value)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\fi
elds\__init__.py", line 1296, in get_prep_value
    return self.to_python(value)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\db\models\fi
elds\__init__.py", line 1399, in to_python
    parsed = parse_datetime(value)
  File "C:\Python27\lib\site-packages\django-1.9.5-py2.7.egg\django\utils\datepa
rse.py", line 93, in parse_datetime
    match = datetime_re.match(value)
TypeError: expected string or buffer

Aside from Selcuk's answer, you might want to avoid setting the methods default to the now() method. I'm pretty sure it won't be executed every time you call the function... just when first initialized — Sayse
@Sayse So do you any idea about how I can give another date instead of now() ? — William P.
now is correct (and I suspect you may still be running the old code and may need to restart the dev server). Simpy set the default to None and then check inside the method if it is none and if so set it to now inside of it — Sayse
@Sayse I restarted the server but nothing changed. I am so sorry but could I ask you where and how I set the default to None ? I am still a newbie ... — William P.

Selcuk Selcuk · Accepted Answer · 2016-06-03T06:38:29

The following line creates a naive (non-timezone aware) datetime:

creationDate = datetime.datetime.now()

Try changing that line to:

creationDate = timezone.now()

Don't forget to import timezone at the beginning of your code:

from django.utils import timezone

python - Django : RunTimeWarning : DateTimeField received a naive datetime while time zone support is active

1 Answers