How to write batch of data to Django's sqlite db from a custom written file? - python-3.x

Question

For a pet project I am working on I need to import list of people to sqlite db. I have 'Staff' model, as well as a users.csv file with list of users. Here is how I am doing it:
import csv
from staff.models import Staff
with open('users.csv') as csv_file:
csv_reader = csv.DictReader(csv_file, delimiter=',')
line_count = 0
for row in csv_reader:
firstname = row['firstname']
lastname = row['lastname']
email = row['email']
staff = Staff(firstname=firstname, lastname=lastname, email=email)
staff.save()
csv_file.close()
However, I am getting below error message:
raise ImproperlyConfigured(
django.core.exceptions.ImproperlyConfigured: Requested setting INSTALLED_APPS, but settings are not configured. You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings.
Is what I am doing correct? If yes what I am missing here?

Answer 1

Django needs some environment variables when it is being bootstrapped to run. DJANGO_SETTINGS_MODULE is one of these, which is then used to configure Django from the settings. Typically many developers don't even notice because if you stay in Django-land it isn't a big deal. Take a look at manage.py and you'll notice it sets it in that file.
The simplest thing is to stay in django-land and run your script in its framework. I recommend creating a management command. Perhaps a more proper way is to create a data migration and put the data in a storage place like S3 if this is something many many people need to do for local databases... but it seems like a management command is the way to go for you. Another option (and the simplest if this is really just a one-time thing) is to just run this from the django shell. I'll put that at the bottom.
It's very simple and you can drop in your code almost as you have it. Here are the docs :) https://docs.djangoproject.com/en/3.2/howto/custom-management-commands/
For you it might look something like this:
/app/management/commands/load_people.py <-- the file name here is what manage.py will use to run the command later.
from django.core.management.base import BaseCommand, CommandError
import csv
from staff.models import Staff
class Command(BaseCommand):
help = 'load people from csv'
def handle(self, *args, **options):
with open('users.csv') as csv_file:
csv_reader = csv.DictReader(csv_file, delimiter=',')
line_count = 0
for row in csv_reader:
firstname = row['firstname']
lastname = row['lastname']
email = row['email']
staff = Staff(firstname=firstname, lastname=lastname, email=email)
staff.save()
# csv_file.close() # you don't need this since you used `with`
which you would call like this:
python manage.py load_people
Finally, the simplest solution is to just run the code in the Django shell.
python manage.py shell
will open up an interactive shell with everything loaded properly. You can execute your code there and it should work.