keep book popularity in model

[wolnelektury.git] / src / catalogue / management / commands / update_popularity.py

diff --git a/src/catalogue/management/commands/update_popularity.py b/src/catalogue/management/commands/update_popularity.py
new file mode 100644 (file)
index 0000000..3a99056
--- /dev/null
+++ b/src/catalogue/management/commands/update_popularity.py
@@ -0,0 +1,24 @@
+# -*- coding: utf-8 -*-
+# This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
+# Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
+#
+from __future__ import print_function, unicode_literals
+
+from django.core.management.base import BaseCommand
+from django.db.models import Count
+
+from catalogue.models import Book, BookPopularity
+
+
+class Command(BaseCommand):
+    help = 'Update popularity counters.'
+
+    def handle(self, **options):
+        BookPopularity.objects.all().delete()
+        books_with_popularity = Book.objects.filter(tag_relations__tag__category='set').only('id').distinct()\
+            .annotate(pop=Count('tag_relations__tag__user', distinct=True))
+        for book in books_with_popularity:
+            BookPopularity.objects.create(book=book, count=book.pop)
+        books_without_popularity = Book.objects.exclude(tag_relations__tag__category='set')
+        for book in books_without_popularity:
+            BookPopularity.objects.create(book=book, count=0)