MarkupField

This is a field that allows multiple markup types but also stores the pre-rendered result in the database which offers an advantage over calling one of the render methods each time. Example usage looks like: class BlogPost(models.Model): ... post = MarkupField() the various extra fields can then be accessed as follows: BlogPost.objects.get(pk=1).post # raw content BlogPost.objects.get(pk=1).post_markup_type # markup type (plain text, html, markdown, rest, textile) BlogPost.objects.get(pk=1).post_rendered # content of post rendered to html BlogPost.objects.get(pk=1).post_as_html # property that access post_rendered but marked safe for easy use in templates After writing my initial version of this I was pointed at the similar http://www.djangosnippets.org/snippets/1169/ I find mine a bit more useful as it includes ReST and includes a mark_safe call to allow showing the rendered HTML directly. I have however borrowed the nice idea of dynamically building MARKUP_TYPES from #1169. Also available via http://gist.github.com/67724.

• fields
• rest
• markup
• markdown
• textile
• restructuredtext

Wed 26 Feb 2014 Read More

Form splitting/Fieldset templatetag

Syntax: `{% get_fieldset list,of,fields as new_form_object from original_form %}` Example: {% load fieldsets %} ... <fieldset id="contact_details"> <legend>Contact details</legend> <ul> {% get_fieldset first_name,last_name,email,cell_phone as personal_fields from form %} {{ personal_fields.as_ul }} </ul> </fieldset> <fieldset> <legend>Address details</legend> <ul> {% get_fieldset street_address,post_code,city as address_fields from form %} {{ address_fields.as_ul }} </ul> </fieldset>

• fields
• forms
• fieldset

Fri 10 May 2013 Read More

Django ChoiceField with "other" choice

See [the blog entry](http://sciyoshi.com/blog/2008/jul/08/django-choicefield-other-choice/) for details.

• newforms
• fields
• choicefield
• other

Thu 16 Jul 2015 Read More

FeaturedModelChoiceField

Here is a way to get a drop down list from a queryset, with a list of "featured" items appearing at the top (from another queryset). This can be used for long select boxes which have a subset of commonly used values. The empty label is used as a separator and values can appear in both the featured set and the full set (it's more usable if they are in both). For example a country drop down list with 5 featured countries might look like this: Andorra Australia Kazakhstan Singapore Turkey ------------ Afghanistan Albania Algeria American Samoa Andorra Angola (hundreds more) To use this, define your form field like this: country = FeaturedModelChoiceField(queryset=Country.objects.all(), featured_queryset=Country.objects.featured())

• fields
• forms

Thu 22 Aug 2013 Read More

EmailListField for Django

A simple Django form field which validates a list of emails. [See this at my blog](http://sciyoshi.com/blog/2009/aug/08/emaillistfield-django/)

• fields
• forms
• email
• form
• field
• email-list

Wed 22 Dec 2010 Read More

Update only selected model fields

Watch out! Previous versions of this snippet (without the values list) were vulnerable to SQL injection attacks. The "correct" solution is probably to wait until [ticket 4102](http://code.djangoproject.com/ticket/4102) hits the trunk. But here's my temporary fix while we wait for that happy day. Django's model.save() method is a PITA: 1. It does a SELECT first to see if the instance is already in the database. 2. It has additional database performance overhead because it writes all fields, not just the ones that have been changed. 3. It overwrites other model fields with data that may be out of date. This is a real problem in concurrent applications, like almost all web apps. If you just want to update a field or two on a model instance which is already in the database, try this: update_fields(user, email='[email protected]', is_staff=True, last_login=datetime.now()) Or you can add it to your models (see below) and then do this: user.update_fields( email='[email protected]', is_staff=True, last_login=datetime.now()) To add it to your model, put it in a module called granular_update, then write this in your models.py: import granular_update class User(models.Model): email = models.EmailField() is_staff = models.BooleanField() last_login = models.DateTimeField() update_fields = granular_update.update_fields

• fields
• model
• save
• performance
• field
• update
• integrity
• consistency

Sun 11 Jul 2010 Read More

UUIDField

UUIDField is a field which stores an uuid generated by pythons new uuid module. it's included with the python 2.5 distribution by default, but if you run an older version of python you can happily copy the file from 2.5 to django/utils/uuid.py or your project directory.

• fields
• field
• uuid

Sun 11 Jul 2010 Read More

assign fields dynamically in newforms

DynamicFieldSnippetForm demonstrates how to dynamically assign fields in newforms. 1. weight is a required static field 2. height is an optional dynamic field This example uses `request_height` as an optional keyword argument to declare whether the `height` field should be added to the form, but it's just there for demonstration purposes. If you decide to use a keyword argument in your code, be sure to pop it off (as demonstrated in the code) or you'll get an *unexpected keyword argument* error.

• newforms
• dynamic
• fields

Sun 11 Jul 2010 Read More

ModelChoiceField & ModelMultipleChoiceField with optgroups

Fields that support HTML optgroups. Adapted from [this snippet](https://djangosnippets.org/snippets/1968/) and updated to work with latest version of Django (1.9) and additional ModelMultipleChoiceField support added. Example Usage: tag = GroupedModelChoiceField(queryset=Tag.objects.all(), group_by_field='parent') positions = GroupedModelMultiChoiceField(queryset=Position.objects.all(), group_by_field='agency')

• fields
• optgroup

Wed 09 May 2018 Read More

ImageField for Google App Engine

This is a replacement for Django's built-in ImageField. It uses the Google AppEngine image APIs in order to validate. Notes: 1. Validation of the field counts against your App Engine transformations quota. 2. This code assumes you're only using the in-memory file upload handler. None of the other stock handlers work well on App Engine; you should probably disable them.

• fields
• imagefield
• google
• appengine
• gae

Sun 11 Jul 2010 Read More

JSONField

This is a custom field that lets you easily store JSON data in one of your model fields. This is updated to work with Django 1.1. **Example: (models.py)** from django.db import models import JSONField class MyModel(models.Model): info = JSONField() ** Example: (shell)** >>> obj = MyModel.objects.all()[0] >>> type(obj.info) <type 'NoneType'> >>> obj.info = {"test": [1, 2, 3]} >>> obj.save() **[Code at GitHub](http://github.com/bradjasper/django-jsonfield/tree/master)**

• models
• fields
• model
• json
• db
• field
• json-field
• jsonfield

Thu 30 May 2013 Read More

ImageWithThumbsField

Easy way to generate image thumbnails for your models. Works with any Storage Backend. From: [http://code.google.com/p/django-thumbs/](http://code.google.com/p/django-thumbs/) **Usage example:** ============== photo = ImageWithThumbsField(upload_to='images', sizes=((125,125),(300,200),) To retrieve image URL, exactly the same way as with ImageField: my_object.photo.url To retrieve thumbnails URL's just add the size to it: my_object.photo.url_125x125 my_object.photo.url_300x200 Note: The 'sizes' attribute is not required. If you don't provide it, ImageWithThumbsField will act as a normal ImageField **How it works:** ============= For each size in the 'sizes' atribute of the field it generates a thumbnail with that size and stores it following this format: available_filename.[width]x[height].extension Where 'available_filename' is the available filename returned by the storage backend for saving the original file. Following the usage example above: For storing a file called "photo.jpg" it saves: photo.jpg (original file) photo.125x125.jpg (first thumbnail) photo.300x200.jpg (second thumbnail) With the default storage backend if photo.jpg already exists it will use these filenames: photo_.jpg photo_.125x125.jpg photo_.300x200.jpg **Note:** It assumes that if filename "any_filename.jpg" is available filenames with this format "any_filename.[widht]x[height].jpg" will be available, too.

• image
• models
• fields
• thumbnail
• field
• thumbnails
• thumbs

Sun 21 Aug 2011 Read More

PositionField

**This is a model field for managing user-specified positions.** Usage ===== Add a `PositionField` to your model; that's just about it. If you want to work with all instances of the model as a single collection, there's nothing else required. In order to create collections based on another field in the model (a `ForeignKey`, for example), set `unique_for_field` to the name of the field. It's probably also a good idea to wrap the `save` method of your model in a transaction since it will trigger another query to reorder the other members of the collection. Here's a simple example: from django.db import models, transaction from positions.fields import PositionField class List(models.Model): name = models.CharField(max_length=50) class Item(models.Model): list = models.ForeignKey(List, db_index=True) name = models.CharField(max_length=50) position = PositionField(unique_for_field='list') # not required, but probably a good idea save = transaction.commit_on_success(models.Model.save) Indices ------- In general, the value assigned to a `PositionField` will be handled like a list index, to include negative values. Setting the position to `-2` will cause the item to be moved to the second position from the end of the collection -- unless, of course, the collection has fewer than two elements. Behavior varies from standard list indices when values greater than or less than the maximum or minimum positions are used. In those cases, the value is handled as being the same as the maximum or minimum position, respectively. `None` is also a special case that will cause an item to be moved to the last position in its collection. Limitations =========== * Unique constraints can't be applied to `PositionField` because they break the ability to update other items in a collection all at once. This one was a bit painful, because setting the constraint is probably the right thing to do from a database consistency perspective, but the overhead in additional queries was too much to bear. * After a position has been updated, other members of the collection are updated using a single SQL `UPDATE` statement, this means the `save` method of the other instances won't be called. More === More information, including an example app and tests, is available on [Google Code](http://code.google.com/p/django-positions/).

• lists
• models
• fields
• model
• field
• list
• sorting
• ordering
• collection
• collections

Tue 20 Oct 2020 Read More

UTC DateTime field

A DateTime field extension that automatically stores the timezone, and the computed UTC equivalent. This field needs the pytz library. The field adds two new fields to the model, with the same name of the UTCDateTimeField field, and a suffix. For an UTCDateTimeField named 'updated', the model will contain * an 'updated' field, which holds the local datetime * an 'updated_utc' field, which holds the corresponding UTC datetime * an 'updated_tz' field, which holds the field timezone name The timezone can vary between model instances, just set the 'xxx_tz' field to the desired timezone before saving. UTCDateTimeField supports a single optional keyword argument 'default_tz', in addition to the DateTimeField standard ones, to let the user choose a provider for a default timezone when no timezone has been set. Its value can be * None (or the argument missing), in which case the default settings.TIME_ZONE will be used * a callable, which will be called when the 'xxx_tz' field is emtpy, which should return a timezone name * a string, which will be used to access a model attribute or call a model method, which should return a timezone name If the timezone name points to a non-existent timezone, a warning will be issued and the default settings.TIME_ZONE value will be used. The field will also add three properties to the model, to access the pytz timezone instance, and the offset aware datetimes for local time and UTC. For the same 'updated' field instance we used above, the three properties added to the model will be: * updated_timezone * updated_offset_aware * updated_utc_offset_aware A brief example on how to use UTCDateTimeField: class UTCDateTimeTest(models.Model): """ >>> import datetime >>> d = datetime.datetime(2007, 8, 24, 16, 46, 34, 762627) # new instance, tz from model method >>> t = UTCDateTimeTest(updated=d) >>> t.save() >>> t.updated datetime.datetime(2007, 8, 24, 16, 46, 34, 762627) >>> t.updated_utc datetime.datetime(2007, 8, 24, 14, 46, 34, 762627) >>> t.updated_tz 'Europe/Rome' >>> t.updated_timezone <DstTzInfo 'Europe/Rome' CET+1:00:00 STD> >>> t.updated_offset_aware datetime.datetime(2007, 8, 24, 16, 46, 34, 762627, tzinfo=<DstTzInfo 'Europe/Rome' CEST+2:00:00 DST>) >>> t.updated_utc_offset_aware datetime.datetime(2007, 8, 24, 14, 46, 34, 762627, tzinfo=<UTC>) >>> """ updated = UTCDateTimeField(default_tz='get_tz') def get_tz(self): return 'Europe/Rome'

• models
• fields
• datetime
• timezone
• field
• utc

Sat 24 Mar 2012 Read More

duplicate model object merging script

Use this function to merge model objects (i.e. Users, Organizations, Polls, Etc.) and migrate all of the related fields from the alias objects the primary object. Usage: from django.contrib.auth.models import User primary_user = User.objects.get(email='[email protected]') duplicate_user = User.objects.get(email='[email protected]') merge_model_objects(primary_user, duplicate_user)

• django
• fields
• model
• generic
• related
• merge
• duplicates
• genericforeignkey

Thu 01 Mar 2012 Read More