Source code for djangochannelsrestframework.permissions

from typing import Dict, Any

from channels.consumer import AsyncConsumer


class OperationHolderMixin:
    def __and__(self, other):
        return OperandHolder(AND, self, other)

    def __or__(self, other):
        return OperandHolder(OR, self, other)

    def __rand__(self, other):
        return OperandHolder(AND, other, self)

    def __ror__(self, other):
        return OperandHolder(OR, other, self)

    def __invert__(self):
        return SingleOperandHolder(NOT, self)


class SingleOperandHolder(OperationHolderMixin):
    def __init__(self, operator_class, op1_class):
        self.operator_class = operator_class
        self.op1_class = op1_class

    def __call__(self, *args, **kwargs):
        op1 = self.op1_class(*args, **kwargs)
        return self.operator_class(op1)


class OperandHolder(OperationHolderMixin):
    def __init__(self, operator_class, op1_class, op2_class):
        self.operator_class = operator_class
        self.op1_class = op1_class
        self.op2_class = op2_class

    def __call__(self, *args, **kwargs):
        op1 = self.op1_class(*args, **kwargs)
        op2 = self.op2_class(*args, **kwargs)
        return self.operator_class(op1, op2)


class AND:
    def __init__(self, op1: "BasePermission", op2: "BasePermission"):
        self.op1 = op1
        self.op2 = op2

    def has_permission(
        self, scope: Dict[str, Any], consumer: AsyncConsumer, action: str, **kwargs
    ):
        return self.op1.has_permission(
            scope, consumer, action, **kwargs
        ) and self.op2.has_permission(scope, consumer, action, **kwargs)


class OR:
    def __init__(self, op1: "BasePermission", op2: "BasePermission"):
        self.op1 = op1
        self.op2 = op2

    def has_permission(
        self, scope: Dict[str, Any], consumer: AsyncConsumer, action: str, **kwargs
    ):
        return self.op1.has_permission(
            scope, consumer, action, **kwargs
        ) or self.op2.has_permission(scope, consumer, action, **kwargs)


class NOT:
    def __init__(self, op1: "BasePermission"):
        self.op1 = op1

    def has_permission(
        self, scope: Dict[str, Any], consumer: AsyncConsumer, action: str, **kwargs
    ):
        return not self.op1.has_permission(scope, consumer, action, **kwargs)


class BasePermissionMetaclass(OperationHolderMixin, type):
    pass


class BasePermission(metaclass=BasePermissionMetaclass):
    """Base permission class

    Notes:
        You should extend this class and override the `has_permission` method to create your own permission class.

    Methods:
        async has_permission (scope, consumer, action, **kwargs)
    """

    async def has_permission(
        self, scope: Dict[str, Any], consumer: AsyncConsumer, action: str, **kwargs
    ) -> bool:
        pass


class AllowAny(BasePermission):
    """Allow any permission class"""

    async def has_permission(
        self, scope: Dict[str, Any], consumer: AsyncConsumer, action: str, **kwargs
    ) -> bool:
        return True


class IsAuthenticated(BasePermission):
    """Allow authenticated only class"""

    async def has_permission(
        self, scope: Dict[str, Any], consumer: AsyncConsumer, action: str, **kwargs
    ) -> bool:
        user = scope.get("user")
        if not user:
            return False
        return user.pk and user.is_authenticated