Disable imports in the UI and view

bookwyrm/templates/import/import.html

@@ -8,6 +8,7 @@
 <div class="block">
     <h1 class="title">{% trans "Import Books" %}</h1>
 
+    {% if site.imports_enabled %}
         {% if recent_avg_hours or recent_avg_minutes %}
         <div class="notification">
             <p>
@@ -85,6 +86,16 @@
             </div>
             <button class="button is-primary" type="submit">{% trans "Import" %}</button>
         </form>
+    {% else %}
+    <div class="box notification has-text-centered is-warning m-6 content">
+        <p class="mt-5">
+            <span class="icon icon-warning is-size-2" aria-hidden="true"></span>
+        </p>
+        <p class="mb-5">
+            {% trans "Imports are temporarily disabled; thank you for your patience." %}
+        </p>
+    </div>
+    {% endif %}
 </div>
 
 <div class="content block">

bookwyrm/views/imports/import_data.py

@@ -4,6 +4,7 @@ import datetime
 
 from django.contrib.auth.decorators import login_required
 from django.db.models import Avg, ExpressionWrapper, F, fields
+from django.core.exceptions import PermissionDenied
 from django.core.paginator import Paginator
 from django.http import HttpResponseBadRequest
 from django.shortcuts import redirect
@@ -54,6 +55,10 @@ class Import(View):
 
     def post(self, request):
         """ingest a goodreads csv"""
+        site = models.Site.objects.get()
+        if not site.imports_enabled:
+            raise PermissionDenied()
+
         form = forms.ImportForm(request.POST, request.FILES)
         if not form.is_valid():
             return HttpResponseBadRequest()