Converts string or int to valid Month.

voluptuous_month.py

class Month(object):
    """Validates a string as a Month of a year

    Args:
        return_type (int): NUMBER = 0, WORD = 1, FULL = 2
        msg (str): the message when it fails
    """
    NUMBER = 0
    WORD = 1
    FULL = 2

    __months_num = range(1, 13)
    __months_full = [
        'January', 'February', 'March', 'April', 'May', 'June',
        'July', 'August', 'September', 'October', 'November', 'December'
    ]
    __months_word = [
        'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
        'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'
    ]

    def __init__(self, return_type=FULL, msg='Not a valid Month value.'):
        self.type = return_type
        self.msg = msg

    def __call__(self, v):
        if isinstance(v, basestring):
            if v.title() in self.__months_full:
                index = self.__months_full.index(v.title())
            elif v.title() in self.__months_word:
                index = self.__months_word.index(v.title())
            else:
                raise Exception(self.msg)
        elif isinstance(v, int):
            if v not in self.__months_num:
                raise Exception(self.msg)
            index = self.__months_num.index(v)
        else:
            raise Exception(self.msg)
        if self.type is self.NUMBER:
            base = self.__months_num
        elif self.type is self.WORD:
            base = self.__months_word
        else:
            base = self.__months_full
        return base[index]

    def __repr__(self):
        if self.type is self.NUMBER:
            _type = 'NUMBER'
        elif self.type is self.WORD:
            _type = 'WORD'
        else:
            _type = 'FULL'
        return 'Month(%s)' % _type