Add BoardMixin, update can_modify

* BoardMixin adds a cached property that gets the current viewed board -
  this assumes that there is a self.kwargs["url"] value available.
* can_modify now checks for some more permissions.

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

board/views.py

@@ -1,6 +1,7 @@
+import functools
 from typing import Any, Dict
 from django.conf import settings
-from django.contrib.auth import get_user_model, get_user
+from django.contrib.auth import get_user
 from django.contrib.auth.mixins import PermissionRequiredMixin
 from django.db.models import Q
 from django.http import Http404, HttpResponseRedirect
@@ -33,14 +34,15 @@ __all__ = (
 )
 
 
-User = get_user_model()
-
-
 def can_modify(user):
     if not user:
         return False
     # TODO add more permissions as required
-    return user.has_perm("board.set_sticky")
+    return (
+        user.has_perm("board.set_sticky")
+        or user.has_perm("board.set_bump")
+        or user.has_perm("board.set_lock")
+    )
 
 
 class BannedView(TemplateView):
@@ -60,7 +62,13 @@ class BannedView(TemplateView):
         return context
 
 
-class CreateView(edit.CreateView):
+class BoardMixin:
+    @functools.cached_property
+    def board(self) -> Board:
+        return get_object_or_404(Board, url=self.kwargs["url"])  # type: ignore
+
+
+class CreateView(BoardMixin, edit.CreateView):
     """
     Helper class that sets a few variables for posts and check against bans.
     This should not be used by itself.
@@ -76,9 +84,6 @@ class CreateView(edit.CreateView):
         return kwargs
 
     def dispatch(self, request, *args, **kwargs):
-        # Set the board on this object
-        self.board = get_object_or_404(Board, url=kwargs["url"])
-
         # Check for bans
         ip = get_client_ip(request)
         if request.method == "POST" and is_banned(ip, self.board):
@@ -87,7 +92,7 @@ class CreateView(edit.CreateView):
             return super(CreateView, self).dispatch(request, *args, **kwargs)
 
 
-class BoardView(TemplateView):
+class BoardView(BoardMixin, TemplateView):
     model = Board
     slug_field = "url"
     slug_url_kwarg = "url"
@@ -101,10 +106,6 @@ class BoardView(TemplateView):
             )
         return super(BoardView, self).get(request, *args, **kwargs)
 
-    def dispatch(self, request, *args, **kwargs):
-        self.board = get_object_or_404(Board, url=kwargs["url"])
-        return super(BoardView, self).dispatch(request, *args, **kwargs)
-
     def get_context_data(self, **kwargs):
         page = self.kwargs["page"]