#25837 closed Uncategorized (invalid)
migration fails when there is initial option set on form field
| Reported by: | Rapolas K. | Owned by: | nobody |
|---|---|---|---|
| Component: | Uncategorized | Version: | 1.9rc1 |
| Severity: | Normal | Keywords: | |
| Cc: | Triage Stage: | Unreviewed | |
| Has patch: | no | Needs documentation: | no |
| Needs tests: | no | Patch needs improvement: | no |
| Easy pickings: | no | UI/UX: | no |
Description
It requires some setup to reproduce it, but essentially: create a new project, create a new app, create a simple form, for example:
from .models import Item
class ReportForm(forms.Form):
items = forms.ModelMultipleChoiceField(
queryset=Item.objects.all(),
widget=forms.CheckboxSelectMultiple,
initial=[item for item in Item.objects.all()])
Import that form in the view and that view in urls and migration starts to fail, complaining about missing table (django.db.utils.OperationalError: no such table: myapp_item). It does work fine in django 1.8. Attaching sample project. Tested on django 1.9rc2 (dropdown doesn't have that version to select)
Attachments (1)
Change History (8)
by , 8 years ago
| Attachment: | mysite.tar.gz added |
|---|
comment:1 by , 8 years ago
| Resolution: | → invalid |
|---|---|
| Status: | new → closed |
You cannot query the database when a file is imported. When you use initial=Item.objects.all(), the query will be lazy, and it won't result in an error. If you need to evaluate the queryset before passing it to initial, you need to do so in the __init__ method of your form.
This probably works fine on 1.8 because you have an existing database in your 1.8 setup. It won't work if you deploy in a new 1.8 environment without an existing database.
comment:2 by , 8 years ago
Have you tried the attached project? It doesn't have any DB inside, and migrations work fine with 1.8 django, but fails with 1.9rc2. So in order to reproduce - download the project, install django 1.8, run ./manage migrate. Works fine. Remove db.sqlite3, install django 1.9rc2, run ./manage migrate. Migrations fail.
comment:3 by , 8 years ago
I took a look through your code, and could not find a reason for your forms to be imported in the migration.
Could you save us the trouble of running it, and just paste your full traceback?
Thanks.
comment:4 by , 8 years ago
(venv)➜ mysite $ python manage.py migrate
Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 350, in execute_from_command_line
utility.execute()
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 342, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/management/base.py", line 348, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/management/base.py", line 398, in execute
self.check()
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/management/base.py", line 426, in check
include_deployment_checks=include_deployment_checks,
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/checks/registry.py", line 75, in run_checks
new_errors = check(app_configs=app_configs)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/checks/urls.py", line 10, in check_url_config
return check_resolver(resolver)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/checks/urls.py", line 19, in check_resolver
for pattern in resolver.url_patterns:
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/utils/functional.py", line 33, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/urlresolvers.py", line 417, in url_patterns
patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/utils/functional.py", line 33, in __get__
res = instance.__dict__[self.name] = self.func(instance)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/core/urlresolvers.py", line 410, in urlconf_module
return import_module(self.urlconf_name)
File "/usr/lib/python2.7/importlib/__init__.py", line 37, in import_module
__import__(name)
File "/home/rapolas/temp/mysite/mysite/urls.py", line 20, in <module>
from myapp import views
File "/home/rapolas/temp/mysite/myapp/views.py", line 4, in <module>
from .forms import ReportForm
File "/home/rapolas/temp/mysite/myapp/forms.py", line 5, in <module>
class ReportForm(forms.Form):
File "/home/rapolas/temp/mysite/myapp/forms.py", line 9, in ReportForm
initial=[item for item in Item.objects.all()])
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/models/query.py", line 258, in __iter__
self._fetch_all()
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/models/query.py", line 1074, in _fetch_all
self._result_cache = list(self.iterator())
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/models/query.py", line 52, in __iter__
results = compiler.execute_sql()
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 852, in execute_sql
cursor.execute(sql, params)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
return super(CursorDebugWrapper, self).execute(sql, params)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/utils.py", line 95, in __exit__
six.reraise(dj_exc_type, dj_exc_value, traceback)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
return self.cursor.execute(sql, params)
File "/home/rapolas/temp/mysite/venv/local/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py", line 323, in execute
return Database.Cursor.execute(self, query, params)
django.db.utils.OperationalError: no such table: myapp_item
(venv)➜ mysite $
comment:5 by , 8 years ago
File "/home/rapolas/temp/mysite/myapp/forms.py", line 9, in ReportForm
initial=[item for item in Item.objects.all()])
Like I said, this executes a query when the form is imported. You need to change it to initial=Item.objects.all().
comment:6 by , 8 years ago
Thanks, it works fine with a change. I don't understand though why it was working in 1.8.7 version.
comment:7 by , 8 years ago
https://docs.djangoproject.com/en/1.9/releases/1.9/#urls
Because before 1.9, urls were not imported until the first request came in (and thus, not at all for migrations)
Sample project