Introduction

django-enum-js is a simple package for sharing a specific implementation of enums with the client through javascript that I developed for Agora.

Use

When writing Django model classes it's common to use an enum-style class to store a few choices. E.g.

class EventState:
    SCHEDULED = u'0'
    LIVE = u'1'
    CANCELLED = u'2'
    CHOICES = [(SCHEDULED, u'Scheduled (but not live yet)'),
               (LIVE, u'Live'),
               (CANCELLED, u'Cancelled')]


class Event(models.Model):
    state = models.CharField(max_length=1, choices=EventState.CHOICES, default=EventState.LIVE)
    ...

Having defined this neat little enum-style class in Django it would be great to be able to communicate and use this enum when writing the client-side code. To do this we just add the following two lines:

from django_enum_js import enum_wrapper
enum_wrapper.register_enum(EventState)

And add the following line to any template where the enums are needed:

<script src="{% url "js_enums" %}" type="text/javascript"></script>

as well as the url to a django file for defining urls (e.g. appname/urls.py):

from django.conf.urls import patterns, include, url
from django_enum_js.views import enums_js

urlpatterns = patterns('',
    url(r'^api/jsenums/$', cache_page(3600)(enums_js), name='js_enums'),
    )

I've set a cache here as I expect the enums not to change very often.

You can now access all the enums through a global javascript variable called Enums.

> Enums.EventState.LIVE
"1"
> Enums.EventState.CHOICES[0]
["0", "Scheduled (but not live yet)"]

Installation

Add django_enum_js to your INSTALLED_APPS in your settings.py file.

Credit

Inspired by django-js-reverse.