src/catalogue/management/commands/update_popularity.py

   1 # -*- coding: utf-8 -*-
   2 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
   3 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
   4 #
   5 from __future__ import print_function, unicode_literals
   6
   7 from django.core.management.base import BaseCommand
   8 from django.db.models import Count
   9
  10 from catalogue.models import Book, BookPopularity
  11
  12
  13 class Command(BaseCommand):
  14     help = 'Update popularity counters.'
  15
  16     def handle(self, **options):
  17         BookPopularity.objects.all().delete()
  18         books_with_popularity = Book.objects.filter(tag_relations__tag__category='set').only('id').distinct()\
  19             .annotate(pop=Count('tag_relations__tag__user', distinct=True))
  20         for book in books_with_popularity:
  21             BookPopularity.objects.create(book=book, count=book.pop)
  22         books_without_popularity = Book.objects.exclude(tag_relations__tag__category='set')
  23         for book in books_without_popularity:
  24             BookPopularity.objects.create(book=book, count=0)