single file Django, DRF project

Question

I am trying to bastardise Django and Django REST Framework into a single module so see if it can work. So far, I have the following code:

###############################################################################
# SETTINGS
###############################################################################
import os
from django.apps import apps
from django.conf import settings

BASE_DIR = os.path.dirname(os.path.dirname(os.path.dirname(__file__)))

if not settings.configured:
    settings.configure(
        DEBUG=True,
        SECRET_KEY='thisisthesecretkey',
        ROOT_URLCONF=__name__,
        STATIC_URL='/static/',
        STATICFILES_DIRS=(
            os.path.join(BASE_DIR, "static"),
        ),
        MIGRATION_MODULES = {'__main__': 'migrations'},
        MIDDLEWARE_CLASSES=(
            'django.middleware.common.CommonMiddleware',
            'django.middleware.csrf.CsrfViewMiddleware',
            'django.middleware.clickjacking.XFrameOptionsMiddleware',
        ),
        DATABASES = {
            'default': {
                'ENGINE': 'django.db.backends.sqlite3',
                'NAME': 'tinydb',
            }
        },
        INSTALLED_APPS = (
            '__main__',
            'rest_framework',
            'django.contrib.staticfiles',
        ),
    )

apps.populate(settings.INSTALLED_APPS)


###############################################################################
# MODELS
###############################################################################
from django.db import models


class Book(models.Model):
    ISBN = models.AutoField(primary_key=True)
    author = models.CharField(max_length=100)
    title = models.CharField(max_length=200)
    description = models.CharField(max_length=500)


###############################################################################
# SERIALIZERS
###############################################################################
from rest_framework import serializers


class BookSerializer(serializers.ModelSerializer):
    class Meta:
        model = Book


###############################################################################
# VIEWS
###############################################################################
class BooksView():
    queryset = Book.objects.all()
    serializer_class = BookSerializer


###############################################################################
# URLCONF
###############################################################################
from django.conf.urls import url, include
from rest_framework.routers import DefaultRouter


router = DefaultRouter()
router.register(r'books', BooksView)

urlpatterns = (
    url(r'^$', include(router.urls)),
)


###############################################################################
# MANAGE
###############################################################################
import sys


if __name__ == "__main__":
    from django.core.management import execute_from_command_line
    execute_from_command_line(sys.argv)

Right now, the server runs and I see the API browser. However, when I try to create an object, I get the following trace:

>>> from __main__ import Book
>>> Book.objects.create(author='a1', title='t1', description='d1')
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/manager.py", line 127, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/query.py", line 348, in create
    obj.save(force_insert=True, using=self.db)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/base.py", line 734, in save
    force_update=force_update, update_fields=update_fields)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/base.py", line 762, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/base.py", line 846, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/base.py", line 885, in _do_insert
    using=using, raw=raw)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/manager.py", line 127, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/query.py", line 920, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/models/sql/compiler.py", line 974, in execute_sql
    cursor.execute(sql, params)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/backends/utils.py", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/utils.py", line 97, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/utils/six.py", line 658, in reraise
    raise value.with_traceback(tb)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/home/lwm/.virtualenvs/tiny-api/lib/python3.4/site-packages/django/db/backends/sqlite3/base.py", line 318, in execute
    return Database.Cursor.execute(self, query, params)
django.db.utils.OperationalError: no such table: __main___book

makemigrations returns:

lwm$ python api.py makemigrations
No changes detected

I can run a migration:

lwm$ python api.py migrate
Operations to perform:
  Synchronize unmigrated apps: __main__, staticfiles, rest_framework
  Apply all migrations: (none)
Synchronizing apps without migrations:
  Creating tables...
    Running deferred SQL...
  Installing custom SQL...
Running migrations:
  No migrations to apply.

So. I think, since I don't have my Book model in a seperate app, there is no database table being created for it. Other than manually creating the tables, for example, using the db_table Meta field, I still wanted to get all the goodness of the ORM doing things for me.

Any ideas?

@decentral1se Just want to know if you did finally find a solution, as I'm actually facing the same problem. Thanks. — Nsukami _, Dec 11 '16 at 17:59
@Nsukami_ Nope, gave up. Let me know if you get somewhere too ;) — , Dec 12 '16 at 18:41
@decentral1se I've found this [link](http://blog.fahhem.com/2011/10/django-models-without-apps-or-everything-django-truly-in-a-single-file/), but all the code is already obsolete. If I find something, I'll let you know. — Nsukami _, Dec 12 '16 at 20:32

score 1 · Answer 1 · edited May 23 '17 at 12:13

1

Try removing __main__ from the list of installed apps. Unless you actually have an app named __main__ (which you probably shouldn't, given that double underscores means something in python), that's not supposed to be there.

edited May 23 '17 at 12:13

Community

1
1

answered Sep 30 '15 at 13:00

eykanal

26,437
19
82
113

Won't work, I get this error then: http://bit.ly/1JClgyL. It's looking for the `app_label` Meta field. This has helped me understand the error though. If I set `app_label` on the `Book` model, then it doesn't look for `__main__` in `INSTALLED_APPS`. It then trys to insert to `_book` which doesn't exist. – Sep 30 '15 at 13:02
@decentral1se - I think you're seeing problems associated with the (very non-standard) way you're building the app. Modules in python require the `__init__.py` file, which indicates that it's a module. You may want to include a `__main__` method in your one-file app, but I don't know enough about python to know what it should contain. – eykanal Sep 30 '15 at 14:03
I appreciate the help but telling me a) I am doing it weird and b) you don't know enough, is not helping. https://stackoverflow.com/help/how-to-answer – Oct 05 '15 at 08:35
@decentral1se - My point is not that you're doing it weird or that I'm too dumb to help, both of which may be true. My point is that all the benefits of a framework like django come with a cost, and that cost is that you have to work within their structure. When you ignore their structure, things break, and you'll have a helluva time figuring out how to fix it. – eykanal Oct 07 '15 at 04:07

score 1 · Answer 2 · answered Jan 10 '17 at 02:39

This is a slightly different code, but it works. I'm using Python 3.6 \o/ and Django 1.10. Keep in mind, if you're currently in a folder named bar and if you save this script as foo.py, you should make your migrations with this command: python foo.py makemigrations bar.

#!/usr/bin/env python
# -*- coding:utf-8 -*-

""" greetings """

import os
import sys
from django.conf import settings

BASE_DIR = os.path.dirname(os.path.abspath(__file__)) 

# use base_dir as import root
sys.path[0] = os.path.dirname(BASE_DIR)

# the current folder name will also be our app
APP_LABEL = os.path.basename(BASE_DIR)


settings.configure(
    DEBUG=os.environ.get('DEBUG', 'on') == 'on',
    SECRET_KEY=os.environ.get('SECRET_KEY', os.urandom(32)),
    ALLOWED_HOSTS=os.environ.get('ALLOWED_HOSTS', 'localhost').split(','),
    ROOT_URLCONF=__name__,
    MIDDLEWARE=[
        'django.middleware.security.SecurityMiddleware',
        'django.contrib.sessions.middleware.SessionMiddleware',
        'django.middleware.common.CommonMiddleware',
        'django.middleware.csrf.CsrfViewMiddleware',
        'django.contrib.auth.middleware.AuthenticationMiddleware',
        'django.contrib.messages.middleware.MessageMiddleware',
        'django.middleware.clickjacking.XFrameOptionsMiddleware',
        'django.middleware.locale.LocaleMiddleware',
        ],
    INSTALLED_APPS=[
        APP_LABEL,
        'django.contrib.admin',
        'django.contrib.auth',
        'django.contrib.contenttypes',
        'django.contrib.sessions',
        'django.contrib.messages',
        'django.contrib.staticfiles',
        'rest_framework',
        ],
    STATIC_URL='/static/',
    STATICFILES_DIRS=[
        os.path.join(BASE_DIR, "static"),
    ],
    STATIC_ROOT=os.path.join(BASE_DIR, "static_root"),
    MEDIA_ROOT=os.path.join(BASE_DIR, "media"),
    MEDIA_URL='/media/',
    TEMPLATES=[
        {
            'BACKEND': 'django.template.backends.django.DjangoTemplates',
            'DIRS': [os.path.join(BASE_DIR, "templates"),],
            'APP_DIRS': True,
            'OPTIONS': {
                'context_processors': [
                    'django.template.context_processors.debug',
                    'django.template.context_processors.i18n',
                    'django.template.context_processors.request',
                    'django.contrib.auth.context_processors.auth',
                    'django.template.context_processors.tz',
                    'django.contrib.messages.context_processors.messages',
                ],
            },
        },
        ],
    DATABASES={
        'default': {
            'ENGINE': 'django.db.backends.sqlite3',
            'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
            }
        },
    REST_FRAMEWORK={
        'DEFAULT_PERMISSION_CLASSES': [
            'rest_framework.permissions.IsAdminUser',
        ],
        'PAGE_SIZE': 10
    }
)


import django
django.setup() # responsible for populating the application registry.


from django.db import models
from django.contrib import admin

from django.db import models

# Create your models here.

class Author(models.Model):
    name = models.CharField(max_length=200)
    class Meta:
        app_label = APP_LABEL

class Book(models.Model):
    author = models.ForeignKey(Author, related_name='books')
    title = models.CharField(max_length=400)
    class Meta:
        app_label = APP_LABEL

admin.site.register(Book)
admin.site.register(Author)
admin.autodiscover()


from rest_framework import serializers

class BookSerializer(serializers.ModelSerializer):
    class Meta:
        model = Book
        fields = '__all__'

from rest_framework import viewsets

class BooksViewSet(viewsets.ReadOnlyModelViewSet):
    queryset = Book.objects.all()
    serializer_class = BookSerializer



from django.conf.urls import url, include
from rest_framework import routers
from django.http import HttpResponse
from django.contrib import admin

router = routers.DefaultRouter()
router.register(r'books', BooksViewSet)

def index(request):
    """ index """
    return HttpResponse("Hello")


urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^$', index, name='homepage'),
    url(r'^api/', include(router.urls)),
    url(r'^api-auth/', include('rest_framework.urls',\
                                   namespace='rest_framework'))
]


from django.core.wsgi import get_wsgi_application
def return_application():
    return get_wsgi_application()

if __name__ == "__main__":
    from django.core.management import execute_from_command_line
    execute_from_command_line(sys.argv)
else:
    return_application()

I hope it helps.

single file Django, DRF project

2 Answers2