5.0 KiB
Permissions
Authentication or identification by itself is not usually sufficient to gain access to information or code. For that, the entity requesting access must have authorization.
Together with authentication and throttling, permissions determine wheter a request should be granted or denied access.
Permission checks are always run at the very start of the view, before any other code is allowed to proceed. Permission checks will typically use the authentication information in the request.user
and request.auth
properties to determine if the incoming request should be permitted.
How permissions are determined
Permissions in REST framework are always defined as a list of permission classes.
Before running the main body of the view each permission in the list is checked.
If any permission check fails an exceptions.PermissionDenied
exception will be raised, and the main body of the view will not run.
Object level permissions
REST framework permissions also support object-level permissioning. Object level permissions are used to determine if a user should be allowed to act on a particular object, which will typically be a model instance.
Object level permissions are run by REST framework's generic views when .get_object()
is called. As with view level permissions, an exceptions.PermissionDenied
exception will be raised if the user is not allowed to act on the given object.
Setting the permission policy
The default permission policy may be set globally, using the DEFAULT_PERMISSIONS
setting. For example.
REST_FRAMEWORK = {
'DEFAULT_PERMISSIONS': (
'rest_framework.permissions.IsAuthenticated',
)
}
You can also set the authentication policy on a per-view basis, using the APIView
class based views.
class ExampleView(APIView):
permission_classes = (IsAuthenticated,)
def get(self, request, format=None):
content = {
'status': 'request was permitted'
}
return Response(content)
Or, if you're using the @api_view
decorator with function based views.
@api_view('GET')
@permission_classes(IsAuthenticated)
def example_view(request, format=None):
content = {
'status': 'request was permitted'
}
return Response(content)
API Reference
IsAuthenticated
The IsAuthenticated
permission class will deny permission to any unauthenticated user, and allow permission otherwise.
This permission is suitable if you want your API to only be accessible to registered users.
IsAdminUser
The IsAdminUser
permission class will deny permission to any user, unless user.is_staff
is True
in which case permission will be allowed.
This permission is suitable is you want your API to only be accessible to a subset of trusted administrators.
IsAuthenticatedOrReadOnly
The IsAuthenticatedOrReadOnly
will allow authenticated users to perform any request. Requests for unauthorised users will only be permitted if the request method is one of the "safe" methods; GET
, HEAD
or OPTIONS
.
This permission is suitable if you want to your API to allow read permissions to anonymous users, and only allow write permissions to authenticated users.
DjangoModelPermissions
This permission class ties into Django's standard django.contrib.auth
model permissions. When applied to a view that has a .model
property, authorization will only be granted if the user has the relevant model permissions assigned.
POST
requests require the user to have theadd
permission on the model.PUT
andPATCH
requests require the user to have thechange
permission on the model.DELETE
requests require the user to have thedelete
permission on the model.
The default behaviour can also be overridden to support custom model permissions. For example, you might want to include a view
model permission for GET
requests.
To use custom model permissions, override DjangoModelPermissions
and set the .perms_map
property. Refer to the source code for details.
The DjangoModelPermissions
class also supports object-level permissions. Third-party authorization backends such as django-guardian that provide object-level permissions should work just fine with DjangoModelPermissions
without any custom configuration required.
Custom permissions
To implement a custom permission, override BasePermission
and implement the .has_permission(self, request, view, obj=None)
method.
The method should return True
if the request should be granted access, and False
otherwise.