Reservationer/assets/validator.py

class validator:
    """
    This is base validator class. It implements base validator mechanism, 
    and other validators must implements it.
    """

    def __init__(self, target: str) -> None:
        """
        This create new validator, from string. 
        
        Parameters:
            target (str): Content to validate
        """

        self.__target = target
        self._failed()

    @property
    def target(self) -> str:
        """ This return content to validate. """

        return self.__target

    def _failed(self) -> None:
        """
        This would mark content as invalid. 
        """

        self.__result = False

    def _check_all(self) -> None:
        """
        This would check all marks of the content.
        It must be overwrite by target validator.
        """

        pass

    def _contain(self, *args) -> bool:
        """
        This check that target contain any given phrase or letter.

        Args:
            (str): Phrase to check that content contain it

        Returns:
            (bool): True when any of given phrase is in the target
        """

        for letter in args:
            if self.__target.find(letter) != -1:
                return True
        
        return False

    @property
    def result(self) -> bool:
        """ Validate content, True when valid or False when not. """

        self.__result = True
        self._check_all()

        return self.__result

    @property
    def invalid(self) -> bool:
        """ Validate, and return True when target is invalid. """
        
        return not self.result

    @property
    def valid(self) -> bool:
        """ It validate target, and return True when valid. """

        return self.result

class name_validator(validator):
    """
    This is validator for product name. It check that it is not blank,
    and it not contain white chars before and after content.
    """

    def _check_all(self) -> None:

        # Could not being blank
        if len(self.target.strip()) == 0:
            return self._failed()

        # Must be trimed
        if len(self.target.strip()) != len(self.target):
            return self._failed()

class description_validator(validator):
    """
    This is validator for product description. It could be blank, but can not
    have white chars before and after content (must be trimmed), and coud has 
    only 500 chars.
    """

    def _check_all(self) -> None:

        # Could be blank
        if len(self.target) == 0:
            return

        # Must be trimmed
        if len(self.target.strip()) != len(self.target):
            return self._failed()

        # Must has max 500 characters.
        if len(self.target) > 500:
            return self._failed()

class barcode_validator(validator):
    """
    This is barcode validator. Barcode must be string, which contain number
    with 8, 12 or 13 digits. That is standard EAN.
    """

    def _check_all(self) -> None:

        # Must has only digits
        if not self.target.isdigit():
            return self._failed()

        lenght = len(self.target)

        # Must has 8, 12 or 13 chars
        if lenght != 8 and lenght != 12 and lenght != 13:
            return self._failed()