# documentação Django 4.0.8.dev20220803071047

# Código fonte para django.contrib.postgres.validators

    from django.core.exceptions import ValidationError
    from django.core.validators import (
        MaxLengthValidator,
        MaxValueValidator,
        MinLengthValidator,
        MinValueValidator,
    )
    from django.utils.deconstruct import deconstructible
    from django.utils.translation import gettext_lazy as _
    from django.utils.translation import ngettext_lazy

    class ArrayMaxLengthValidator(MaxLengthValidator):
        message = ngettext_lazy(
            "List contains %(show_value)d item, it should contain no more than "
            "%(limit_value)d.",
            "List contains %(show_value)d items, it should contain no more than "
            "%(limit_value)d.",
            "limit_value",
        )

    class ArrayMinLengthValidator(MinLengthValidator):
        message = ngettext_lazy(
            "List contains %(show_value)d item, it should contain no fewer than "
            "%(limit_value)d.",
            "List contains %(show_value)d items, it should contain no fewer than "
            "%(limit_value)d.",
            "limit_value",
        )

    @deconstructible
    class KeysValidator:
        """A validator designed for HStore to require/restrict keys."""

        messages = {
            "missing_keys": _("Some keys were missing: %(keys)s"),
            "extra_keys": _("Some unknown keys were provided: %(keys)s"),
        }
        strict = False

        def __init__(self, keys, strict=False, messages=None):
            self.keys = set(keys)
            self.strict = strict
            if messages is not None:
                self.messages = {**self.messages, **messages}

        def __call__(self, value):
            keys = set(value)
            missing_keys = self.keys - keys
            if missing_keys:
                raise ValidationError(
                    self.messages["missing_keys"],
                    code="missing_keys",
                    params={"keys": ", ".join(missing_keys)},
                )
            if self.strict:
                extra_keys = keys - self.keys
                if extra_keys:
                    raise ValidationError(
                        self.messages["extra_keys"],
                        code="extra_keys",
                        params={"keys": ", ".join(extra_keys)},
                    )

        def __eq__(self, other):
            return (
                isinstance(other, self.__class__)
                and self.keys == other.keys
                and self.messages == other.messages
                and self.strict == other.strict
            )

    class RangeMaxValueValidator(MaxValueValidator):
        def compare(self, a, b):
            return a.upper is None or a.upper > b

        message = _(
            "Ensure that this range is completely less than or equal to %(limit_value)s."
        )

    class RangeMinValueValidator(MinValueValidator):
        def compare(self, a, b):
            return a.lower is None or a.lower < b

        message = _(
            "Ensure that this range is completely greater than or equal to %(limit_value)s."
        )