Alias admin with 2-char prefixes

services/admin.py

@@ -1,6 +1,43 @@
 from django.contrib import admin
+from django.contrib.admin import SimpleListFilter
+from django.utils.translation import ugettext_lazy as _
 from services.models import Service, ServiceType, Alias
 
+
+# See
+# <http://docs.djangoproject.com/en/dev/ref/contrib/admin/#django.contrib.admin.ModelAdmin.list_filter>
+# for documentation
+class StartsWithListFilter(SimpleListFilter):
+    title = _('Starts with')
+
+    parameter_name = 'starts_with'
+
+    def lookups(self, request, model_admin):
+        def first_two(s):
+            s = unicode(s)
+            if len(s) < 2:
+                return s
+            else:
+                return s[:2]
+
+        prefixes = [first_two(alias.name)
+                    for alias in model_admin.model.objects.only('name')]
+
+        prefixes = sorted(set(prefixes))
+
+        return [(prefix, prefix) for prefix in prefixes]
+
+    def queryset(self, request, queryset):
+        if self.value():
+            return queryset.filter(name__istartswith=self.value())
+        else:
+            return queryset
+
+
+class AliasAdmin(admin.ModelAdmin):
+    list_filter = (StartsWithListFilter,)
+
+
 admin.site.register(Service)
 admin.site.register(ServiceType)
-admin.site.register(Alias)
+admin.site.register(Alias, AliasAdmin)

services/models.py

@@ -79,6 +79,7 @@ class Meta:
             ("manage_aliases", "Can manage aliases"),
         )
         ordering = ["name"]
+        verbose_name_plural = "aliases"
 
     def expire(self, time=None):
         if time == None: