Cache template snipped for shelve buttons

bookwyrm/views/reading.py

@@ -1,5 +1,7 @@
 """ the good stuff! the books! """
 from django.contrib.auth.decorators import login_required
+from django.core.cache import cache
+from django.core.cache.utils import make_template_fragment_key
 from django.db import transaction
 from django.http import HttpResponse, HttpResponseBadRequest, HttpResponseNotFound
 from django.shortcuts import get_object_or_404, redirect
@@ -44,6 +46,10 @@ class ReadingStatus(View):
         if not identifier:
             return HttpResponseBadRequest()
 
+        # invalidate the template cache
+        cache_key = make_template_fragment_key("shelve_button", [request.user.id, book_id])
+        cache.delete(cache_key)
+
         desired_shelf = get_object_or_404(
             models.Shelf, identifier=identifier, user=request.user
         )