update primary key (and cascade to child tables)
Management command to update a primary key and update all child-tables with a foreign key to this table.
- primary-key
- cascade
Snippet List
Clean Reversion History: Remove unimportant Changes
If you use this pattern to track changes in the auth user table: from django.contrib.auth.models import User from reversion.helpers import patch_admin patch_admin(User) you can't see important changes, since a version is created for every login if a user. If you want to get rid of changes which only change unimportant stuff you can use this middleware. This middleware can be used for every model. Just use this pattern in your settings: REVERSION_CLEAN={ 'django.contrib.auth': {'User': ['last_login']}, }
- reversion
ReadOnlyWidget
See docstring
- widget
- readonly
ImportObject: Import model *instance* specific code at runtime
See docstring
- contenttypes
StringListField (database field)
This django.db.models.Field stores a list of python strings in one database column.
- field
Cookie based Messages (deprecated)
DEPRECATED: Django has cookie based messages since version 1.2 This messages stores messages for the user in a cookie. I prefer this to session based messages, because the session column is a hot spot in the database if one user works with several browser tabs/windows.
Overwrite some views in settings.py
If you app defines some URLs with a name, and you want to overwrite this at project level with a different view you can use this snippet. You only need to change on line in the application code (the import statement).
- urls
- settings
- reverse
decoupling authorization from calling the view
has_perm.py: Check if a user can access a view without calling it One of the goals: You can disable or hide a link if the user must not call it.
- authentication
- has_perm
Database Schema Upgrade (deprecated)
Deprecated! I use south in all applications with database backend now.
- deprecated
urlquote() and urlencode() in one method
I think this method is handy, since you don't need to remember if you need urlquote or urlencode. It does both and adds a question mark between the path and the get parameters, if later are present. And it works around a bug in Django: MultiValueDicts (request.GET, request.POST) are handled correctly. Related: [http://code.djangoproject.com/ticket/9089](http://code.djangoproject.com/ticket/9089)
- urlquote
- urlencode
Add ValidationError to a field instead of __all__ during Form.clean()
If you need two values for validation, you can't use clean_value_a() since it is undefined if value_a or value_b gets cleaned first. This little helper lets you add ValidationErrors to fields instead of \__all\__. Related [Ticket 5335](http://code.djangoproject.com/ticket/5335).
- errordict
Timedelta Database Field
This subclass of django.models.Field stores a python datetime.timedelta object as an integer column in the database. It includes a TimedeltaFormField for editing it through djangos admin interface. Feedback welcome. 2011-04-20: TimedeltaField can now be (de)serialized. Tested with JSON. 2009-11-23: `_has_changed()` added. Before form.changed_data contained timedelta FormFields, even if nothing changed.
- datetime
- timedelta
- dbfield
breadcrumbs
With this script you can create a simple breadcrumbs line for navigation: Home >> Page >> Subpage ...
- breadcrumbs
Unittest: Compare max_size with column size of database
Changing the size of max_length in the model is fast. But sometimes you forget to update all running systems which use this model. This unittest helps you to find the difference between Model and DB before the users get uncaught exceptions.
- unittest
Add HTML Attributes in Model
Maybe there is a better solution, feedback welcome!
- form_for_model
- modelform
guettli has posted 22 snippets.