Intro
django-typed-models provides an extra type of model inheritance for Django. It is similar to single-table inheritance in Ruby on Rails.
The concrete type of each object is stored in the database, and when the object is retrieved it is automatically cast to the correct concrete type.
Licensed under the New BSD License.
Features
Automatic downcasting of models from querysets
All models subclassing a common base are stored in the same table
object types are stored in a ‘type’ field in the database
No extra queries or joins to retrieve multiple types
Usage:
An example says a bunch of words:
# myapp/models.py
from django.db import models
from typedmodels import TypedModel
class Animal(TypedModel):
"""
Abstract model
"""
name = models.CharField(max_length=255)
def say_something(self):
raise NotImplemented
def __repr__(self):
return u'<%s: %s>' % (self.__class__.__name__, self.name)
class Canine(Animal):
def say_something(self):
return "woof"
class Feline(Animal):
mice_eaten = models.IntegerField(
default = 0
)
def say_something(self):
return "meoww"
# later >>> from myapp.models import Animal, Canine, Feline >>> Feline.objects.create(name="kitteh") >>> Feline.objects.create(name="cheetah") >>> Canine.objects.create(name="fido") >>> print Animal.objects.all() [<Feline: kitteh>, <Feline: cheetah>, <Canine: fido>] >>> print Canine.objects.all() [<Canine: fido>] >>> print Feline.objects.all() [<Feline: kitteh>, <Feline: cheetah>]
You can actually change the types of objects. Simply run an update query:
Feline.objects.update(type='myapp.bigcat')
If you want to change the type of an object without refreshing it from the database, you can call recast:
kitty.recast(BigCat)
# or kitty.recast('myapp.bigcat')
kitty.save()
Limitations
Since all objects are stored in the same table, all fields defined in subclasses are nullable.
Known issues
Error in South migration when m2m field related to model not inheriting directly from TypedModel is used.
XML serialization doesn’t work.
Requirements
Python 2.7 or 3.3+
Django 1.7+
Release files for django-typed-models 0.5.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| django-typed-models-0.5.0.tar.gz | 10.2 kB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| django_typed_models-0.5.0-py2.py3-none-any.whl | Python 2, Python 3 | none | any | Details |
Total release size: 20.9 kB
Release files / django-typed-models-0.5.0.tar.gz
| Download URL | django-typed-models-0.5.0.tar.gz |
|---|---|
| Size | 10.2 kB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
ea2a1bc49cf6b9506f3820d1639ebf614314b1a6400b77d4fc08eff0b4c1cee0
|
|
BLAKE2b-256 checksum How to use checksums |
58f1b4a5b6057711a286782b044b3f189ef198b7cd862fc01f4ad803e2d00916
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
No |
Release files / django_typed_models-0.5.0-py2.py3-none-any.whl
| Download URL | django_typed_models-0.5.0-py2.py3-none-any.whl |
|---|---|
| Size | 10.7 kB |
| Tags | Python 2 Python 3 |
|
SHA-256 checksum How to use checksums |
56cf6f3e5f94518d7d91e5feebfc662961f84188c0a0f7e877d9f2b63ea62678
|
|
BLAKE2b-256 checksum How to use checksums |
8af253e8117a1f2421b4bf49c5fca196ee4f682a116ac7633f1a88d17542e0d9
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
No |