Django Channels permissions

Question

Is there any supported way in Django Channels framework to write custom permission to connect to specific consumers?

something like DRF:

class MyConsumer(generics.APIView):
    permission_classes = [IsAuthenticated, MyCustomPermission]
    authentication_classes = [TokenAuthentication]

Answer 1

For anyone looking for a solution, I've come up with this solution:

1. Create a Permissions class with a check_permissions method.

    from channels.exceptions import DenyConnection

    class Permissions(object):
        permission_classes = []
    
        def check_permissions(self):
            try:
                for permission in self.permission_classes:
                    if permission(scope=self.scope).validate() != None:
                        raise DenyConnection
            except PermissionError:
                raise DenyConnection

2. Create a BasePermission class.

class BasePermission(object):
    def __init__(self, scope, *args, **kwargs) -> None:
        self.scope = scope

    def has_permission(self, *args, **kwargs) -> bool:
        return True

    def validate(self, *args, **kwargs):
        try:
            if not self.has_permission(*args, **kwargs):
                return PermissionError
        except Exception:
            return RuntimeError
        return None

3. Then override has_perm with your custom permission.

class NotAnonymousUser(BasePermission):

    def has_permission(self, *args, **kwargs) -> bool:
        try:
            return not isinstance(self.scope["user"],AnonymousUser)
        except Exception:
            return False

4. Finally inherit the Permissions class and call the check_permissions method.

class MyConsumer(Permissions, JsonWebsocketConsumer):
    permission_classes = [NotAnonymousUser]

    def connect(self):
        self.check_permissions()
                   .
                   .