Utils

Utility Functions

chamber.utils.remove_accent(string_with_diacritics)

chamber.utils.get_class_method(cls_or_inst, method_name)

Returns a method of a given class or instance.

chamber.utils.forms.formset_has_file_field()

Returns True if passed formset contains FileField (or ImageField).

chamber.utils.http.query_string_from_dict()

Assembles query string from a Python dict.

>>> query_string_from_dict({'q': 'query1', 'user': 'test'})
u'q=query1&user=test'

Enums

class chamber.utils.datastructures.AbstractEnum

Base enumeration class with controlled __getattr__.

class chamber.utils.datastructures.Enum

Python’s set with AbstractEnum behaviour.

class chamber.utils.datastructures.NumEnum

Python’s dict with AbstractEnum behaviour.

>>> NumEnum('a', 'b')
{'a': 1, 'b': 2}

class chamber.utils.datastructures.AbstractChoicesEnum

Base choices class (can be used as a model field’s choices argument).

class chamber.utils.datastructures.ChoicesEnum

django.utils.datastructures.SortedDict with AbstractEnum and AbstractChoicesEnum behaviour. Useful for string based choices.

>>> enum = ChoicesEnum(('OK', 'ok'), ('KO', 'ko'))
>>> enum
{'OK': 'ok', 'KO': 'ko'}
>>> enum.OK
'ok'
>>> enum.choices
[('OK', 'ok'), ('KO', 'ko')]

class chamber.utils.datastructures.ChoicesNumEnum

django.utils.datastructures.SortedDict with AbstractEnum and AbstractChoicesEnum behaviour. Useful for integer-based choices.

>>> enum = ChoicesNumEnum(('OK', 'ok', 1), ('KO', 'ko', 2))
>>> enum.KO
2
>>> enum.choices
[(1, 'ok'), (2, 'ko')]
>>> enum.get_label(2)
'ko'

Decorators

@chamber.utils.decorators.classproperty

Decorator that turns a class method into a property of the class.

class RestResource(BaseResource):
    @classproperty
    def csrf_exempt(cls):
        return not cls.login_required

    @classmethod
    def as_view(cls, allowed_methods=None, **initkwargs):
        view.csrf_exempt = cls.csrf_exempt

@chamber.utils.decorators.singleton

Class decorator, which allows for only one instance of class to exist.

@chamber.utils.decorators.short_description

Sets short_description attribute that is used to render description of a Django form field.

@short_description('amount')
def absolute_amount(self):
    return abs(self.amount)

is equivalent to

def absolute_amount(self):
    return abs(self.amount)
absolute_amount.short_description = 'amount'