Django Rest compare user id 'sector' id with publication 'sector' id

Well, I found the solution in a different way, I made a filter on the objects by the sector id, and it looked like this:

ps: I also put an OR condition to search for the 'General' sector, which should appear for all users

from django.db.models import Q 

class PostListAPIView(ListAPIView):
queryset = Post.objects.all()
serializer_class = PostSerializer

def get_queryset(self):
    user_sector = None
    if self.request.user.is_authenticated():
        user_sector = self.request.user.sector.id
        queryset = Post.objects.filter(
                        Q(sector__id=user_sector) |
                        Q(sector__name='Geral')
                        ).distinct()   
        return queryset

There's more to a permission issue, so I understand. So when the publishing sector is different from the user sector you want to decline that request (and probably return an error message).

I would implement it as follows:

class PostDetailAPIView(RetrieveAPIView):
 queryset = Post.objects.all()
 serializer_class = PostSerializer
 permission_classes = (ClasseVerificacao)

Then you need to implement the " Verification Class "

# CLASSES PARA CONTROLE DE PERMISSIONS
class ClasseVerificacao(permissions.BasePermission):
  message = 'Permissão negada, seu setor não é o mesmo do objeto'

  def has_object_permission(self, request, view, obj):
    return self.request.user.sector == obj.sector

Notice that this part returns True when the user sector is equal to the sector of the object. When the function returns True it responds to the request, if the function returns False it responds to the request with the message you have chosen.

  

return self.request.user.sector == obj.sector

Well it's "complicated" to make the code exactly for your problem, there is an example that should help you. And remember to look at the documentation.