Merge branch 'reflow'

[wolnelektury.git] / apps / catalogue / helpers.py

diff --git a/apps/catalogue/helpers.py b/apps/catalogue/helpers.py
deleted file mode 100644 (file)
index 7ca2cbd..0000000
--- a/apps/catalogue/helpers.py
+++ /dev/null
@@ -1,58 +0,0 @@
-# -*- 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 django.contrib.contenttypes.models import ContentType
-from django.db.models import Count
-from .models import Tag, Book
-
-
-BOOK_CATEGORIES = ('author', 'epoch', 'genre', 'kind')
-
-
-def get_top_level_related_tags(tags=None, categories=BOOK_CATEGORIES):
-    """
-    Finds tags related to given tags through books, and counts their usage.
-
-    Takes ancestry into account: if a tag is applied to a book, its
-    usage on the book's descendants is ignored.
-
-    This is tested for PostgreSQL 9.1+, and might not work elsewhere.
-    It particular, it uses raw SQL using WITH clause, which is
-    supported in SQLite from v. 3.8.3, and is missing in MySQL.
-    http://bugs.mysql.com/bug.php?id=16244
-
-    """
-    # First, find all tag relations of relevant books.
-    bct = ContentType.objects.get_for_model(Book)
-    relations = Tag.intermediary_table_model.objects.filter(
-        content_type=bct)
-    if tags is not None:
-        tagged_books = Book.tagged.with_all(tags).only('pk')
-        relations = relations.filter(
-            object_id__in=tagged_books).exclude(
-            tag_id__in=[tag.pk for tag in tags])
-
-    rel_sql, rel_params = relations.query.sql_with_params()
-
-    # Exclude those relations between a book and a tag,
-    # for which there is a relation between the book's ancestor
-    # and the tag and 
-
-    return Tag.objects.raw('''
-        WITH AllTagged AS (''' + rel_sql + ''')
-        SELECT catalogue_tag.*, COUNT(catalogue_tag.id) AS count
-        FROM catalogue_tag, AllTagged
-        WHERE catalogue_tag.id=AllTagged.tag_id
-            AND catalogue_tag.category IN %s
-            AND NOT EXISTS (
-                SELECT AncestorTagged.id
-                FROM catalogue_book_ancestor Ancestor,
-                    AllTagged AncestorTagged
-                WHERE Ancestor.from_book_id=AllTagged.object_id
-                    AND AncestorTagged.content_type_id=%s
-                    AND AncestorTagged.object_id=Ancestor.to_book_id
-                    AND AncestorTagged.tag_id=AllTagged.tag_id
-            )
-        GROUP BY catalogue_tag.id
-        ORDER BY sort_key''', rel_params + (categories, bct.pk))