Get date from a Django DateTimeField
Question:
I would like to request some assistance regarding this matter
I am learning django and trying out some codes but I hit a brick wall at trying to get the date only from a model’s DateTimeField
here’s the code that I am working on:
class APPLICANT_DATA(models.Model):
SCHEDULED_AT = models.DateTimeField(null=True, blank=True)
def somefunction():
app_data = APPLICANT_DATA.objects.all()
for item in app_data:
the_date = str(item.SCHEDULED_AT.strftime("%B-%d-%Y")) + ", " + the _date
And I am getting ('NoneType' object has no attribute 'strftime') even though my model contains 3 records that all have date and time
What am I doing wrong? any advice for a newbie? many thanks.
Answers:
SCHEDULED_AT is set to null=True, so sometimes item.SCHEDULED_AT doesn’t have value so it’s None. If you do a .strftime on None it will have the error you got. null=True means django model allows the field to have NULL value.
By the way, it’s really bad practice to use all upper case for model and field names, model name should be camel case and fields should be lower case with underscore. You model name should be ApplicantData, field name should be scheduled_at.
DateTimeField becomes a datetime.datetime object in Python
If you need a date object to manipulate later on, you could pull the datetime.date object directly from your DateTimeField(), using datetime.datetime.date() like below:
class ApplicantData(models.Model):
scheduled_at = models.DateTimeField(null=True, blank=True)
date = application_data.scheduled_at.date()
This works because Django will translate the DateTimeField into the Python type datetime.datetime, upon which we have called date().
Format the datetime.date like you wish
Then from that, you get a datetime.date object, that you can format like you wish, using datetime.date.strftime().
If you don’t need a date object, you can also use strftime on your datetime.datetime object too, no problems with that. Except that your had a None field in your object.
Dealing with NULL/None fields
If you want to allow for NULL values in scheduled_at you can do:
if application_data.scheduled_at is not None:
date = application_data.scheduled_at.date()
While in the given example the problem is most probably due to the object truly being None, as said in other answers, please note that you might come across such a situation in test code if you forget to clean your data by calling, e.g. full_clean() on your DateTimeField as in :
test_obj = YourModel(
date=datetime.datetime(2016,2,26,tzfinfo=GM1),
...
)
test_obj.full_clean() # <-- don't forget this or you'll get a NoneType object
test_obj.save()
I would like to request some assistance regarding this matter
I am learning django and trying out some codes but I hit a brick wall at trying to get the date only from a model’s DateTimeField
here’s the code that I am working on:
class APPLICANT_DATA(models.Model):
SCHEDULED_AT = models.DateTimeField(null=True, blank=True)
def somefunction():
app_data = APPLICANT_DATA.objects.all()
for item in app_data:
the_date = str(item.SCHEDULED_AT.strftime("%B-%d-%Y")) + ", " + the _date
And I am getting ('NoneType' object has no attribute 'strftime') even though my model contains 3 records that all have date and time
What am I doing wrong? any advice for a newbie? many thanks.
SCHEDULED_AT is set to null=True, so sometimes item.SCHEDULED_AT doesn’t have value so it’s None. If you do a .strftime on None it will have the error you got. null=True means django model allows the field to have NULL value.
By the way, it’s really bad practice to use all upper case for model and field names, model name should be camel case and fields should be lower case with underscore. You model name should be ApplicantData, field name should be scheduled_at.
DateTimeField becomes a datetime.datetime object in Python
If you need a date object to manipulate later on, you could pull the datetime.date object directly from your DateTimeField(), using datetime.datetime.date() like below:
class ApplicantData(models.Model):
scheduled_at = models.DateTimeField(null=True, blank=True)
date = application_data.scheduled_at.date()
This works because Django will translate the DateTimeField into the Python type datetime.datetime, upon which we have called date().
Format the datetime.date like you wish
Then from that, you get a datetime.date object, that you can format like you wish, using datetime.date.strftime().
If you don’t need a date object, you can also use strftime on your datetime.datetime object too, no problems with that. Except that your had a None field in your object.
Dealing with NULL/None fields
If you want to allow for NULL values in scheduled_at you can do:
if application_data.scheduled_at is not None:
date = application_data.scheduled_at.date()
While in the given example the problem is most probably due to the object truly being None, as said in other answers, please note that you might come across such a situation in test code if you forget to clean your data by calling, e.g. full_clean() on your DateTimeField as in :
test_obj = YourModel(
date=datetime.datetime(2016,2,26,tzfinfo=GM1),
...
)
test_obj.full_clean() # <-- don't forget this or you'll get a NoneType object
test_obj.save()