django-enumfield 1.0.1

Custom Django field for using enumerations of named constants

django-enumfield
==============

Provides an enumeration Django model field (using IntegerField) with reusable enums and transition validation.

.. image:: https://travis-ci.org/5monkeys/django-enumfield.png?branch=master
:target: http://travis-ci.org/5monkeys/django-enumfield

Installation
------------

Install django-enumfield in your python environment

.. code:: sh

$ pip install django-enumfield

Usage
-----

Create an Enum-class and pass it as first argument to the Django model EnumField.

.. code:: python

from django.db import models
from django_enumfield import enum

class BeerStyle(enum.Enum):
LAGER = 0
STOUT = 1
WEISSBIER = 2

class Beer(models.Model):
style = enum.EnumField(BeerStyle, default=BeerStyle.LAGER)

.. code:: python

Beer.objects.create(style=BeerStyle.STOUT)
Beer.objects.filter(style=BeerStyle.STOUT)

The Enum-class provides the possibility to use transition validation.

.. code:: python

from django.db import models
from django_enumfield import enum

class PersonStatus(enum.Enum):
ALIVE = 1
DEAD = 2
REANIMATED = 3

_transitions = {
DEAD: (ALIVE,),
REANIMATED: (DEAD,)
}

class Person(models.Model):
status = enum.EnumField(PersonStatus)

These transitions state that a PersonStatus can only go to DEAD from ALIVE and to REANIMATED from DEAD.

.. code:: python

person = Person.objects.create(status=PersonStatus.ALIVE)
try:
person.status = PersonStatus.REANIMATED
person.save()
except InvalidStatusOperationError:
print "Person status can not go from ALIVE to REANIMATED"

The Enum-class can also be used without the EnumField. This is very useful in Django form ChoiceFields.

.. code:: python

from django.forms import Form
from django_enumfield import enum

class GenderEnum(enum.Enum):
MALE = 1
FEMALE = 2

class PersonForm(forms.Form)
gender = forms.TypedChoiceField(choices=GenderEnum.choices(), coerce=int)

Rendering PersonForm in a template will generate a select-box with "Male" and "Female" as option labels for the gender field.