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What do I need to import to gain access to my models? (5)

Depending on your specific needs, django-command-extensions might save you a bit of time. To run any script as-is without messing around with environment variables just type:

./manage.py runscript path/to/my/script.py

django-command-extensions also has commands for automating scripts as cron jobs, which is something you mentioned that you'd like to do.

If you are a more nuts and bolts type of person, you might check out this very detailed post outlining how to make "standalone" django scripts to be run from cron jobs and whatnot.

I'd like to run a script to populate my database. I'd like to access it through the Django database API.

The only problem is that I don't know what I would need to import to gain access to this.

How can this be achieved?


If you use the shell argument to the manage.py script in your project directory, you don't have to import the settings manually:

$ cd mysite/
$ ./manage.py shell
Python 2.5.2 (r252:60911, Jun 10 2008, 10:35:34) 
[GCC 4.0.1 (Apple Inc. build 5465)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from myapp.models import *
>>>

For non-interactive use you could implement a custom command and run it with manage.py.


The preferred way should be to add a custom command and then run it as any other django-admin (not to be confused with django.contrib.admin) command:

./manage.py mycustomcommand --customarg

Setting DJANGO_SETTINGS_MODULE should only be used when a custom command is not feasible.


This is what I have at the top of one my data loading scripts.

import string
import sys
try:
    import settings # Assumed to be in the same directory.
    #settings.DISABLE_TRANSACTION_MANAGEMENT = True
except ImportError:
    sys.stderr.write("Error: Can't find the file 'settings.py' in the directory containing %r. It appears you've customized things.\nYou'll have to run django-admin.py, passing it your settings module.\n(If the file settings.py does indeed exist, it's causing an ImportError somehow.)\n" % __file__)
sys.exit(1)

#Setup the django environment with the settings module.
import django
import django.core.management
django.core.management.setup_environ(settings)

from django.db import transaction

This should all execute before you do much else in your script.

Another method is to use fixtures and manage.py. Though if you are just trying to accomplish a bulk data load to initialize a database this should work fine.

Also depending on what you are doing you may or may not want to do it all in one transaction. Uncomment the transaction line above and structure your code similar to this.

transaction.enter_transaction_management()
try:
    #Do some stuff
    transaction.commit()
finally:
    transaction.rollback()
    pass
transaction.leave_transaction_management()

Django: How can I use my model classes to interact with my database from outside Django?

You need to set up the Django environment variables. These tell Python where your project is, and what the name of the settings module is (the project name in the settings module is optional):

import os

os.environ['PYTHONPATH'] = '/path/to/myproject'
os.environ['DJANGO_SETTINGS_MODULE'] = 'myproject.settings'

Now you should be able to access the models:

from myproject.models import MyModel

all_my_models = MyModel.objects.all()




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