When deleting objects in Django's admin interface, it lists other objects which would be deleted and asks for confirmation. This snippet does the same programmatically.
The snippet works in Django 1.3 (more specifically, revision 14507 or later). It uses Django internals which are not a part of the public API, so this might not work with future versions.
Usage:
`polls/models.py`:
from django.db import models
class Poll(models.Model):
question = models.CharField(max_length=200)
def __unicode__(self):
return self.question
class Choice(models.Model):
poll = models.ForeignKey(Poll)
choice = models.CharField(max_length=200)
def __unicode__(self):
return '%s %s' % (self.poll, self.choice)
`$ ./manage.py shell`
>>> from polls.models import Poll, Choice
>>> from datetime import datetime
>>> from pprint import pprint
>>> poll1 = Poll.objects.create(question='Me?')
>>> Choice.objects.create(poll=poll1, choice='Yes')
>>> Choice.objects.create(poll=poll1, choice='No')
>>> poll2 = Poll.objects.create(question='Really?')
>>> Choice.objects.create(poll=poll2, choice='Yes')
>>> Choice.objects.create(poll=poll2, choice='No')
>>> pprint(get_related(Poll.objects.all()))
{<class 'polls.models.Poll'>: [<Poll: Me?>, <Poll: Really?>],
<class 'polls.models.Choice'>: [<Choice: Me? Yes>,
<Choice: Me? No>,
<Choice: Really? Yes>,
<Choice: Really? No>]}
This server-side middleware implements some of the functionality in the Yahoo
User Interface Loader component. YUI JavaScript and CSS modules requirements
can be declared anywhere in the base, inherited or included templates, and the
resulting, optimized `<script>` and `<link rel="stylesheet">` tags are inserted at
the specified position of the resulting page.
Requirements may be specified in multiple locations. This is useful when zero
or more components are included in the HTML head section, and inherited and/or
included templates require possibly overlapping sets of YUI components in the
body across inherited and included templates. All tags are collected in the
head section, and duplicate tags are automatically eliminated.
The middleware understands component dependencies and ensures that resources
are loaded in the right order. It knows about built-in rollup files that ship
with YUI. By automatically using rolled-up files, the number of HTTP requests
is reduced.
The default syntax looks like HTML comments. Markup for the insertion point is
replaced with `<script>` and `<link>` tags:
<!-- YUI_init -->
Component requirements are indicated, possibly in multiple locations, with the
`YUI_include` markup. It is removed from the resulting page by the
middleware. Example:
<!-- YUI_include fonts grids event dragdrop -->
Non-minified and compressed versions are requested, respectively, by:
<!-- YUI_version raw -->
<!-- YUI_version debug -->
Example:
<html><head>
<!-- YUI_init -->
<!-- YUI_include dom event -->
</head><body>
<!-- YUI_include element selector reset fonts base -->
</body></html>
Renders:
<html><head>
<link rel="stylesheet" type="text/css" href="http://yui.yahooapis.com/2.5.1/build/reset-fonts/reset-fonts.css" />
<link rel="stylesheet" type="text/css" href="http://yui.yahooapis.com/2.5.1/build/base/base-min.css" />
<script type="text/javascript" src="http://yui.yahooapis.com/2.5.1/build/yahoo-dom-event/yahoo-dom-event.js"></script>
<script type="text/javascript" src="http://yui.yahooapis.com/2.5.1/build/element/element-beta-min.js"></script>
<script type="text/javascript" src="http://yui.yahooapis.com/2.5.1/build/selector/selector-beta-min.js"></script>
</head><body>
</body></html>
The markup format can be customized with global Django settings. Example:
YUI_INCLUDE_PREFIX_RE = r'{!'
YUI_INCLUDE_SUFFIX_RE = r'!}'
would change markup to e.g. `{! init !}` and `{! include dom event !}`.
The base URL is customized with the `YUI_INCLUDE_BASE` setting, e.g.:
YUI_INCLUDE_BASE = 'http://localhost:8000/yui/build/'
To remove the XHTML trailing slash from the `<link>` tag, use:
YUI_INCLUDE_CSS_TAG = '<link rel="stylesheet" type="text/css" href="%s">'
See also the [home page for this module](http://trac.ambitone.com/ambidjangolib/wiki/YUI_include).
This middleware replaces the behavior of the APPEND_SLASH setting in the CommonMiddleware. Please set `APPEND_SLASH = False` and `SMART_APPEND_SLASH = True` if you are going to use this middleware.
In your URL patterns, omit the trailing slash for URLs you want accessible without the slash. Include the slash for those URLs you wish to be automatically redirected from an URL with the slash missing.
If a URL pattern exists both with and without a slash, they are treated as two distinct URLs and no redirection is done.
Example
urlpatterns = patterns('some_site.some_app.views',
(r'^test/no_append$','test_no_append'),
(r'^test/append/$','test_append'),
(r'^test/distinct_url$', 'view_one'),
(r'^test/distinct_url/$', 'view_two'), )
Behavior of URLs against the above patterns with SMART_APPEND_SLASH enabled:
http://some_site/test/no_append → test_no_append()
http://some_site/test/no_append/ → 404
http://some_site/test/append → http://some_site/test/append/
http://some_site/test/append/ → test_append()
http://some_site/test/distinct_url → view_one()
http://some_site/test/distinct_url/ → view_two()
This module is also available [in our SVN repository](http://trac.ambitone.com/ambidjangolib/browser/trunk/middleware/common.py).