TIL 220825

라이브러리 임포트 순서

• 표준 라이브러리 --> 코어 장고 --> 서드 파티

코어장고

from django.utils.translation import gettext_lazy as _

import 부문

from common.utils import utils
from apps.agent.models import Agent
from .managers import MemberManager

class ActiveStatus(models.TextChocies):

class ActiveStatus(models.TextChoices):
    WAIT = "WAIT", _("WAIT")
    ACTIVE = "ACTIVE", _("ACTIVE")
    DEACTIVE = "DEACTIVE", _("DEACTIVE")

lazy(func, *resultclasses)

def lazy(func, *resultclasses):
    """
    Turn any callable into a lazy evaluated callable. result classes or types
    is required -- at least one is needed so that the automatic forcing of
    the lazy evaluation code is triggered. Results are not memoized; the
    function is evaluated on every access.
    """

    @total_ordering
    class __proxy__(Promise):
        """
        Encapsulate a function call and act as a proxy for methods that are
        called on the result of that function. The function is not evaluated
        until one of the methods on the result is called.
        """
        __prepared = False

        def __init__(self, args, kw):
            self.__args = args
            self.__kw = kw
            if not self.__prepared:
                self.__prepare_class__()
            self.__class__.__prepared = True

        def __reduce__(self):
            return (
                _lazy_proxy_unpickle,
                (func, self.__args, self.__kw) + resultclasses
            )

        def __repr__(self):
            return repr(self.__cast())

        @classmethod
        def __prepare_class__(cls):
            for resultclass in resultclasses:
                for type_ in resultclass.mro():
                    for method_name in type_.__dict__:
                        # All __promise__ return the same wrapper method, they
                        # look up the correct implementation when called.
                        if hasattr(cls, method_name):
                            continue
                        meth = cls.__promise__(method_name)
                        setattr(cls, method_name, meth)
            cls._delegate_bytes = bytes in resultclasses
            cls._delegate_text = str in resultclasses
            assert not (cls._delegate_bytes and cls._delegate_text), (
                "Cannot call lazy() with both bytes and text return types.")
            if cls._delegate_text:
                cls.__str__ = cls.__text_cast
            elif cls._delegate_bytes:
                cls.__bytes__ = cls.__bytes_cast

        @classmethod
        def __promise__(cls, method_name):
            # Builds a wrapper around some magic method
            def __wrapper__(self, *args, **kw):
                # Automatically triggers the evaluation of a lazy value and
                # applies the given magic method of the result type.
                res = func(*self.__args, **self.__kw)
                return getattr(res, method_name)(*args, **kw)
            return __wrapper__

        def __text_cast(self):
            return func(*self.__args, **self.__kw)

        def __bytes_cast(self):
            return bytes(func(*self.__args, **self.__kw))

        def __bytes_cast_encoded(self):
            return func(*self.__args, **self.__kw).encode()

        def __cast(self):
            if self._delegate_bytes:
                return self.__bytes_cast()
            elif self._delegate_text:
                return self.__text_cast()
            else:
                return func(*self.__args, **self.__kw)

        def __str__(self):
            # object defines __str__(), so __prepare_class__() won't overload
            # a __str__() method from the proxied class.
            return str(self.__cast())

        def __eq__(self, other):
            if isinstance(other, Promise):
                other = other.__cast()
            return self.__cast() == other

        def __lt__(self, other):
            if isinstance(other, Promise):
                other = other.__cast()
            return self.__cast() < other

        def __hash__(self):
            return hash(self.__cast())

        def __mod__(self, rhs):
            if self._delegate_text:
                return str(self) % rhs
            return self.__cast() % rhs

        def __deepcopy__(self, memo):
            # Instances of this class are effectively immutable. It's just a
            # collection of functions. So we don't need to do anything
            # complicated for copying.
            memo[id(self)] = self
            return self

    @wraps(func)
    def __wrapper__(*args, **kw):
        # Creates the proxy object, instead of the actual value.
        return __proxy__(args, kw)

    return __wrapper__

class RegexValidator

@deconstructible
class RegexValidator:
    regex = ''
    message = _('Enter a valid value.')
    code = 'invalid'
    inverse_match = False
    flags = 0

    def __init__(self, regex=None, message=None, code=None, inverse_match=None, flags=None):
        if regex is not None:
            self.regex = regex
        if message is not None:
            self.message = message
        if code is not None:
            self.code = code
        if inverse_match is not None:
            self.inverse_match = inverse_match
        if flags is not None:
            self.flags = flags
        if self.flags and not isinstance(self.regex, str):
            raise TypeError("If the flags are set, regex must be a regular expression string.")

        self.regex = _lazy_re_compile(self.regex, self.flags)

    def __call__(self, value):
        """
        Validate that the input contains (or does *not* contain, if
        inverse_match is True) a match for the regular expression.
        """
        regex_matches = self.regex.search(str(value))
        invalid_input = regex_matches if self.inverse_match else not regex_matches
        if invalid_input:
            raise ValidationError(self.message, code=self.code)

    def __eq__(self, other):
        return (
            isinstance(other, RegexValidator) and
            self.regex.pattern == other.regex.pattern and
            self.regex.flags == other.regex.flags and
            (self.message == other.message) and
            (self.code == other.code) and
            (self.inverse_match == other.inverse_match)
        )

_lazy_re_compile(regex, flags=0)

def _lazy_re_compile(regex, flags=0):
    """Lazily compile a regex with flags."""
    def _compile():
        # Compile the regex if it was not passed pre-compiled.
        if isinstance(regex, (str, bytes)):
            return re.compile(regex, flags)
        else:
            assert not flags, (
                'flags must be empty if regex is passed pre-compiled'
            )
            return regex
    return SimpleLazyObject(_compile)