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Django migration fails 'QuerySet' object has no attribute 'objects'

I have a set of models:
class DebugConf(models.Model):
is_setup = models.BooleanField(default=False)
debug_setup_date = models.DateTimeField()
def __str__(self):
return self.is_setup
class Currency(models.Model):
currency_name = models.CharField(max_length=100)
currency_value_in_dollars = models.FloatField()
currency_value_in_dollars_date = models.DateTimeField()
def __str__(self):
return self.currency_name
class User(models.Model):
user_name = models.CharField(max_length=200)
user_pass = models.CharField(max_length=200)
join_date = models.DateTimeField()
def __str__(self):
return self.user_name
class Transaction(models.Model):
transaction_type = models.CharField(max_length=200)
transaction_amount = models.FloatField()
transaction_date = models.DateTimeField()
transaction_currency = models.ForeignKey(Currency, on_delete=models.CASCADE)
transaction_users = models.ForeignKey(User, on_delete=models.CASCADE)
def __str__(self):
return self.headline
a project 'crypto' and an app 'manage_crypto_currency' nested into it:
The app's views contains some initialization code:
views.py:
if IS_DEBUG_MODE:
print('[!!!INFO!!!] DEBUG MODE SET! USING GENERATED TABLES')
init_debug_tables()
def init_debug_tables():
# Check if debug table has already been initialized
debug_conf = DebugConf.objects.all()
if debug_conf.objects.exists():
return
At the moment, the db is not initialized; when running:
python manage.py makemigrations manage_crypto_currency
in the root (project dir):
I get:
[!!!INFO!!!] DEBUG MODE SET! USING GENERATED TABLES
Traceback (most recent call last):
File "manage.py", line 24, in <module>
main()
File "manage.py", line 20, in main
execute_from_command_line(sys.argv)
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
utility.execute()
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\core\management\__init__.py", line 395, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\core\management\base.py", line 330, in run_from_argv
self.execute(*args, **cmd_options)
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\core\management\base.py", line 368, in execute
self.check()
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\core\management\base.py", line 392, in check
all_issues = checks.run_checks(
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\core\checks\registry.py", line 70, in run_checks
new_errors = check(app_configs=app_configs, databases=databases)
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\core\checks\urls.py", line 13, in check_url_config
return check_resolver(resolver)
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\core\checks\urls.py", line 23, in check_resolver
return check_method()
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\urls\resolvers.py", line 408, in check
for pattern in self.url_patterns:
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\utils\functional.py", line 48, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\urls\resolvers.py", line 589, in url_patterns
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\utils\functional.py", line 48, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\urls\resolvers.py", line 582, in urlconf_module
return import_module(self.urlconf_name)
File "C:\Users\msebi\AppData\Local\Programs\Python\Python38-32\lib\importlib\__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
File "<frozen importlib._bootstrap>", line 991, in _find_and_load
File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 783, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "C:\projects\django\crypto-currency-board\crypto\crypto\urls.py", line 21, in <module>
path('', include('manage_crypto_currency.urls')),
File "C:\projects\django\crypto-currency-board\venv\lib\site-packages\django\urls\conf.py", line 34, in include
urlconf_module = import_module(urlconf_module)
File "C:\Users\msebi\AppData\Local\Programs\Python\Python38-32\lib\importlib\__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
File "<frozen importlib._bootstrap>", line 991, in _find_and_load
File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 783, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "C:\projects\django\crypto-currency-board\crypto\manage_crypto_currency\urls.py", line 5, in <module>
from . import views
File "C:\projects\django\crypto-currency-board\crypto\manage_crypto_currency\views.py", line 24, in <module>
init_debug_tables()
File "C:\projects\django\crypto-currency-board\crypto\manage_crypto_currency\setup_test_db\setup_debug_tables.py", line 14, in init_debug_tables
if debug_conf.objects.exists():
AttributeError: 'QuerySet' object has no attribute 'objects'
The line:
[!!!INFO!!!] DEBUG MODE SET! USING GENERATED TABLES
is in views. Apparently, the migrations tool feels the need to execute views.py. Why on Earth, I have no clue. Is it possible to make makemigrations NOT execute code that it shouldn't, e.g. just create the models given that the db is not initialized?
EDIT
The answers don't answer WHY migrate runs views.py (I don't know either), but commenting out:
# if IS_DEBUG_MODE:
# print('[!!!INFO!!!] DEBUG MODE SET! USING GENERATED TABLES')
# init_debug_tables()
leads to successful migration. Is there a less cumbersome way to go about it? (Un)comment is ugly.

You don't need to use call the objects of a QuerySet
def init_debug_tables():
# Check if debug table has already been initialized
debug_conf = DebugConf.objects.all()
if debug_conf.exists(): # instead of `debug_conf.objects.exists()`
return

As the error message suggest, debug_conf is the the model class, it is an instance of a QuerySet.
objects is the Manager attached to a model class. This managers creates QuerySet for you (in your code, by the return value of the all method).
So you want to do this:
def init_debug_tables():
# Check if debug table has already been initialized
debug_conf = DebugConf.objects.all()
if debug_conf.exists():
return

Error using Textfield and charfield model in Django

I have been trying to use Textfield in class but the suggestions just does not show up. Instead i receive an error in my Cmd console. This was even the case while using CharField.
Below is my code:
from django.db import models
from django.db.models import CharField
from django.db.models import Textfield
from datetime import datetime
class Posts(models.Model):
title = models.CharField(max_length=200)
body = models.TextField()
created_at = models.DateTimeField(default=datetime.now, blank=True)
This is the error i get in my CMD:
Exception in thread django-main-thread:
Traceback (most recent call last):
File "d:\python\python38\lib\threading.py", line 932, in _bootstrap_inner
self.run()
File "d:\python\python38\lib\threading.py", line 870, in run
self._target(*self._args, **self._kwargs)
File "C:\Users\USER\Envs\py1\lib\site-packages\django\utils\autoreload.py", line 53, in wrapper
fn(*args, **kwargs)
File "C:\Users\USER\Envs\py1\lib\site-packages\django\core\management\commands\runserver.py", line
109, in inner_run
autoreload.raise_last_exception()
File "C:\Users\USER\Envs\py1\lib\site-packages\django\utils\autoreload.py", line 76, in
raise_last_exception
raise _exception[1]
File "C:\Users\USER\Envs\py1\lib\site-packages\django\core\management\__init__.py", line 357, in
execute
autoreload.check_errors(django.setup)()
File "C:\Users\USER\Envs\py1\lib\site-packages\django\utils\autoreload.py", line 53, in wrapper
fn(*args, **kwargs)
File "C:\Users\USER\Envs\py1\lib\site-packages\django\__init__.py", line 24, in setup
apps.populate(settings.INSTALLED_APPS)
File "C:\Users\USER\Envs\py1\lib\site-packages\django\apps\registry.py", line 114, in populate
app_config.import_models()
File "C:\Users\USER\Envs\py1\lib\site-packages\django\apps\config.py", line 211, in import_models
self.models_module = import_module(models_module_name)
File "d:\python\python38\lib\importlib\__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
File "<frozen importlib._bootstrap>", line 991, in _find_and_load
File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 671, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 783, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "E:\Python\djangoproject\posts\models.py", line 3, in <module>
from django.db.models import Textfield
ImportError: cannot import name 'Textfield' from 'django.db.models' (C:\Users\USER\Envs\py1\lib\site-
packages\django\db\models\__init__.py)

Actually you don't need to import the fields separately, you could use the django.db.models that you have imported earlier.
And the error is produced because you should use TextField with a capital F

encountering errors while adding a foreign key in models.py

I wanted to migrate some models but the ones with the foreignkey functions are causing some problems.
I ran the following code and it caused an error
python manage.py migrate
and the foreign key seems the problem
class Webpage(models.Model):
topic =models.ForeignKey(Topic)
name = models.CharField(max_length=264 , unique=True)
url = models.URLField(unique=True)
def __str__(self):
return self.name
Traceback (most recent call last):
File "C:\Users\helin\Anaconda3\envs\myenv\lib\sitepackages\django\utils\autoreload.py", line 225, in wrapper fn(*args, **kwargs)
File "C:\Users\helin\Anaconda3\envs\myenv\lib\site-packages\django\core\management\commands\runserver.py", line 109, in inner_run
autoreload.raise_last_exception()
File "C:\Users\helin\Anaconda3\envs\myenv\lib\site-packages\django\utils\autoreload.py", line 248, in raise_last_exception
raise _exception[1]
File "C:\Users\helin\Anaconda3\envs\myenv\lib\site-packages\django\core\management\__init__.py", line 337, in execute autoreload.check_errors(django.setup)()
File "C:\Users\helin\Anaconda3\envs\myenv\lib\sitepackages\django\utils\autoreload.py", line 225, in wrapper fn(*args, **kwargs)
File "C:\Users\helin\Anaconda3\envs\myenv\lib\site-packages\django\__init__.py", line 24, in setup
apps.populate(settings.INSTALLED_APPS)
File "C:\Users\helin\Anaconda3\envs\myenv\lib\site-packages\django\apps\registry.py", line 112, in populate
app_config.import_models()
File "C:\Users\helin\Anaconda3\envs\myenv\lib\site-packages\django\apps\config.py", line 198, in import_models
self.models_module = import_module(models_module_name)
File "C:\Users\helin\Anaconda3\envs\myenv\lib\importlib\__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 985, in _gcd_import
File "<frozen importlib._bootstrap>", line 968, in _find_and_load
File "<frozen importlib._bootstrap>", line 957, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 673, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 697, in exec_module
File "<frozen importlib._bootstrap>", line 222, in _call_with_frames_removed
File "C:\Users\helin\Downloads\my_django\first_project\first_app\models.py", line 12, in <module>
class Webpage(models.Model):
File "C:\Users\helin\Downloads\my_django\first_project\first_app\models.py", line 13, in Webpage
topic =models.ForeignKey(Topic)
TypeError: __init__() missing 1 required positional argument: 'on_delete'

Yes, you are missing 1 required positional argument: 'on_delete'.
When using foreign key, you need to pass 'on_delete' argument to it. This will make sure that whenever the table/ record to which this foreign key is a primary key is deleted it will automatically delete/protect the record of the table where it acts as a foreign key.
Example:
class Customer(models.Model):
customer_id = <something>
class Account(models.Model):
customer_id = models.ForeignKey(Customer, on_delete=models.CASCADE)
So, when a customer with customer_id = x is deleted in Customer related table, it will delete the corresponding record in the Account table.
You can read about it here

from adaptor.model import CsvModel

I am trying to use the CsvModel module from django-adaptors. However, when i use from adaptor.model import CsvModel and makemigrations, below errors occured.
Can anyone advise the reason why? my code in the model is as follows:
from django.db import models
from adaptor.model import CsvModel
from adaptor.fields import CharField, DecimalField
class User(models.Model):
user_name = models.CharField(max_length = 50, null=True, unique=True)
def __str__(self):
return self.user_name
class Profile(models.Model):
rubbish = models.DecimalField(max_digits= 1000, decimal_places=3, null=True)
user = models.CharField(max_length = 50, unique = True, null=True)
hobby = models.CharField(max_length = 50, null=True)
job = models.CharField(max_length = 60, null=True)
class Trial(CsvModel):
rubbish = DecimalField()
user = CharField()
hobby = CharField()
class Meta:
dbmodel = Profile
delimiter = ','
has_header = True
Error message is as follows:
File "manage.py", line 15, in <module>
execute_from_command_line(sys.argv)
File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 371, in execute_from_command_line
utility.execute()
File "/usr/local/lib/python3.6/site-packages/django/core/management/__init__.py", line 347, in execute
django.setup()
File "/usr/local/lib/python3.6/site-packages/django/__init__.py", line 24, in setup
apps.populate(settings.INSTALLED_APPS)
File "/usr/local/lib/python3.6/site-packages/django/apps/registry.py", line 112, in populate
app_config.import_models()
File "/usr/local/lib/python3.6/site-packages/django/apps/config.py", line 198, in import_models
self.models_module = import_module(models_module_name)
File "/usr/local/Cellar/python/3.6.4_3/Frameworks/Python.framework/Versions/3.6/lib/python3.6/importlib/__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 994, in _gcd_import
File "<frozen importlib._bootstrap>", line 971, in _find_and_load
File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 678, in exec_module
File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
File "/Users/pangkachun/Desktop/smallpro2/small_pro/small/models.py", line 2, in <module>
from adaptor.model import CsvModel
File "/usr/local/lib/python3.6/site-packages/adaptor/model.py", line 269
except ValueError, e:
^ . `

You are using python3.6 but the library looks like it is made for python2.5-
For Python 3 it should be
except ValueError as e:
source
You may have to find a different csv plugin like django-csvimport and possibly change your strategy accordingly

I'm getting problems uploading images in django

This is the models.py file. Although you can see that i have used MEDIA_URL as the directory for the image to be saved, i have also messed around with all other alternatives getting similar error messages. Could this have something to do with permissions? im not sure.
from django.db import models
from taggit.managers import TaggableManager
class Post(models.Model):
title = models.CharField(max_length = 100)
body = models.TextField()
created = models.DateTimeField()
image1 = models.ImageField(upload_to = MEDIA_URL)
def __unicode__(self):
return self.title
This is the settings part i have added.
MEDIA_ROOT = os.path.join(BASE_DIR, 'media')
MEDIA_URL = '/media/'
And this is the error message i am getting in the cmd(using windows)
Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "C:\Python34\lib\site-packages\django\core\management\__init__.py", line 399, in execute_from_command_line
utility.execute()
File "C:\Python34\lib\site-packages\django\core\management\__init__.py", line 392, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "C:\Python34\lib\site-packages\django\core\management\base.py", line 242, in run_from_argv
self.execute(*args, **options.__dict__)
File "C:\Python34\lib\site-packages\django\core\management\base.py", line 284, in execute
self.validate()
File "C:\Python34\lib\site-packages\django\core\management\base.py", line 310, in validate
num_errors = get_validation_errors(s, app)
File "C:\Python34\lib\site-packages\django\core\management\validation.py", line 34, in get_validation_errors
for (app_name, error) in get_app_errors().items():
File "C:\Python34\lib\site-packages\django\db\models\loading.py", line 196, in get_app_errors
self._populate()
File "C:\Python34\lib\site-packages\django\db\models\loading.py", line 75, in _populate
self.load_app(app_name, True)
File "C:\Python34\lib\site-packages\django\db\models\loading.py", line 99, in load_app
models = import_module('%s.models' % app_name)
File "C:\Python34\lib\importlib\__init__.py", line 109, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap>", line 2254, in _gcd_import
File "<frozen importlib._bootstrap>", line 2237, in _find_and_load
File "<frozen importlib._bootstrap>", line 2226, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 1200, in _load_unlocked
File "<frozen importlib._bootstrap>", line 1129, in _exec
File "<frozen importlib._bootstrap>", line 1471, in exec_module
File "<frozen importlib._bootstrap>", line 321, in _call_with_frames_removed
File "C:\Users\Neema\sonder\blog\models.py", line 4, in <module>
class Post(models.Model):
File "C:\Users\Neema\sonder\blog\models.py", line 8, in Post
image1 = models.ImageField(upload_to = MEDIA_URL)
NameError: name 'MEDIA_URL' is not defined

I think you need to add a import to your models.py:
from django.conf import settings
And then you can use it:
settings.MEDIA_URL
Anyway, I don't think it is a good practice to add the MEDIA_URL to your field. If in the future you decide to change it, you need to update all the DB entries.

Don't mention MEDIA_URL in your models.py at all. Just mention a subdirectory name. For e.g.
image1 = models.ImageField(upload_to="blogimages")
Make sure that the media folder has write access by server (Apache or IIS). This is a common problem in Windows. It can be fixed easily by right clicking the folder and changing the permissions.
If you still get an error, please post that as well.