Object level permissions

Really we'd like all code snippets to be visible to anyone, but also make sure that only the user that created a code snippet is able to update or delete it.

To do that we're going to need to create a custom permission.

In the snippets app, create a new file, permissions.py

from rest_framework import permissions
class IsOwnerOrReadOnly(permissions.BasePermission):
    """
    Custom permission to only allow owners of an object to edit it.
    """
    def has_object_permission(self, request, view, obj):
        # Read permissions are allowed to any request,
        # so we'll always allow GET, HEAD or OPTIONS requests.
        if request.method in permissions.SAFE_METHODS:
            return True
        # Write permissions are only allowed to the owner of the snippet.
        return obj.owner == request.user

Now we can add that custom permission to our snippet instance endpoint, by editing the permission_classes property on the SnippetDetail view class:

permission_classes = [permissions.IsAuthenticatedOrReadOnly,
                      IsOwnerOrReadOnly]

Make sure to also import the IsOwnerOrReadOnly class.

from snippets.permissions import IsOwnerOrReadOnly

Now, if you open a browser again, you find that the 'DELETE' and 'PUT' actions only appear on a snippet instance endpoint if you're logged in as the same user that created the code snippet.