Choice Fields (Or Enum equivalent) refactors

I am working on Issue #291 . I cant help but notice the code snippets like if conference.status != 1: from junction/proposals/views.py (It might be in some other places too). It is not immediately apparent what 1 represents. I have to open junction/base/constants.py to cross-reference with the file and understand what it is.

So I am raising an Issue here to propose a refactor. To deal with choices field I wrote a handy decorator. It goes something like this:

import inspect


def user_attributes(cls):
    defaults = dir(type('defaults', (object,), {}))  # gives all inbuilt attrs
    return [
        item[0] for item in inspect.getmembers(cls) if item[0] not in defaults]


def choices(cls):
    """
    Decorator to set `CHOICES` attribute
    """
    _choices = []
    for attr in user_attributes(cls):
        val = getattr(cls, attr)
        _choices.append((val, attr))
    setattr(cls, 'CHOICES', tuple(_choices))
    return cls


@choices
class FooEnum:
    FOO = 1
    BAR = 2

print FooEnum.CHOICES  # Will contain `((2, 'BAR'), (1, 'FOO'))`

I also understand we might need some custom get_<choice_field>_display messages. For that I think we can tweak the choices decorator to do the same. That will be something like this.

import inspect


def user_attributes(cls):
    defaults = dir(type('defaults', (object,), {}))  # gives all inbuilt attrs
    return [
        item[0] for item in inspect.getmembers(cls) if item[0] not in defaults]


def choices(cls):
    """
    Decorator to set `CHOICES` and other attributes
    """
    _choices = []
    for attr in user_attributes(cls):
        val = getattr(cls, attr)
        setattr(cls, attr[1:], val[0])
        _choices.append((val[0], val[1]))
    setattr(cls, 'CHOICES', tuple(_choices))
    return cls


@choices
class FooEnum:
    _FOO = [1, "Some Foo String"]
    _BAR = [2, "Some Bar String"]

print FooEnum.CHOICES  # ((2, 'Some Bar String'), (1, 'Some Foo String'))
print FooEnum.FOO  # 1

So we could do something like if conference.status != ConferenceStatus.ACCEPTING_CFP: which makes code base A bit readable and pragmatic.

Any thoughts @kracekumar ?

[kracekumar]

@dhilipsiva Sure, but one feature which will be useful is reverse lookup. If choice Public is 1, db contains 1, while returning the data via api, field need to bare the value as Public not 1.

[dhilipsiva]

@kracekumar I created a stand alone decorator for doing this dhilipsiva/orm-choices. Would it be okay if I refactored this code to use the orm-choices library and send a PR?