# Python 2.3 compatibility
try:
set
-except NameError:
+except NameError:
from sets import Set as set
from django.contrib.contenttypes import generic
def __init__(self, intermediary_table_model):
super(TagManager, self).__init__()
self.intermediary_table_model = intermediary_table_model
-
+
def update_tags(self, obj, tags):
"""
Update tags associated with an object.
current_tags = list(self.filter(items__content_type__pk=content_type.pk,
items__object_id=obj.pk))
updated_tags = self.model.get_tag_list(tags)
-
+
# Remove tags which no longer apply
tags_for_removal = [tag for tag in current_tags \
if tag not in updated_tags]
for tag in updated_tags:
if tag not in current_tags:
self.intermediary_table_model._default_manager.create(tag=tag, content_object=obj)
-
+
def remove_tag(self, obj, tag):
"""
Remove tag from an object.
ctype = ContentType.objects.get_for_model(obj)
return self.filter(items__content_type__pk=ctype.pk,
items__object_id=obj.pk)
-
- def _get_usage(self, model, counts=False, min_count=None, extra_joins=None, extra_criteria=None, params=None, extra=None, extra_tables=None):
+
+ def _get_usage(self, model, counts=False, min_count=None, extra_joins=None, extra_criteria=None, params=None, extra=None):
"""
Perform the custom SQL query for ``usage_for_model`` and
``usage_for_queryset``.
model_table = qn(model._meta.db_table)
model_pk = '%s.%s' % (model_table, qn(model._meta.pk.column))
tag_columns = self._get_tag_columns()
-
+
if extra is None: extra = {}
extra_where = ''
if 'where' in extra:
extra_where = 'AND ' + ' AND '.join(extra['where'])
-
+
query = """
SELECT DISTINCT %(tag_columns)s%(count_sql)s
FROM
%(tag)s
- INNER JOIN %(tagged_item)s AS %(tagged_item_alias)s
- ON %(tag)s.id = %(tagged_item_alias)s.tag_id
+ INNER JOIN %(tagged_item)s
+ ON %(tag)s.id = %(tagged_item)s.tag_id
INNER JOIN %(model)s
- ON %(tagged_item_alias)s.object_id = %(model_pk)s
+ ON %(tagged_item)s.object_id = %(model_pk)s
%%s
- WHERE %(tagged_item_alias)s.content_type_id = %(content_type_id)s
+ WHERE %(tagged_item)s.content_type_id = %(content_type_id)s
%%s
%(extra_where)s
- GROUP BY %(tag_columns)s, %(tag)s.id, %(tag)s.name%(extra_tables)s
+ GROUP BY %(tag_columns)s, %(tag)s.id, %(tag)s.name
%%s
ORDER BY %(tag)s.%(ordering)s ASC""" % {
'tag': qn(self.model._meta.db_table),
'tag_columns': tag_columns,
'count_sql': counts and (', COUNT(%s)' % model_pk) or '',
'tagged_item': qn(self.intermediary_table_model._meta.db_table),
- 'tagged_item_alias': qn('_newtagging_' + self.intermediary_table_model._meta.db_table),
'model': model_table,
'model_pk': model_pk,
'extra_where': extra_where,
- 'extra_tables': ''.join((', %s.id' % qn(table)) for table in extra_tables),
'content_type_id': ContentType.objects.get_for_model(model).pk,
}
extra_joins = ' '.join(queryset.query.get_from_clause()[0][1:])
where, params = queryset.query.where.as_sql()
- extra_tables = queryset.query.extra_tables
if where:
extra_criteria = 'AND %s' % where
else:
extra_criteria = ''
- return self._get_usage(queryset.model, counts, min_count, extra_joins, extra_criteria, params, extra, extra_tables=extra_tables)
+ return self._get_usage(queryset.model, counts, min_count, extra_joins, extra_criteria, params, extra)
def related_for_model(self, tags, model, counts=False, min_count=None, extra=None):
"""
tag_count = len(tags)
tagged_item_table = qn(self.intermediary_table_model._meta.db_table)
tag_columns = self._get_tag_columns()
-
+
if extra is None: extra = {}
extra_where = ''
if 'where' in extra:
extra_where = 'AND ' + ' AND '.join(extra['where'])
-
+
# Temporary table in this query is a hack to prevent MySQL from executing
# inner query as dependant query (which could result in severe performance loss)
query = """
def __init__(self, tag_model):
super(TaggedItemManager, self).__init__()
self.tag_model = tag_model
-
+
def get_by_model(self, queryset_or_model, tags):
"""
Create a ``QuerySet`` containing instances of the specified
def create_intermediary_table_model(model):
"""Create an intermediary table model for the specific tag model"""
name = model.__name__ + 'Relation'
-
+
class Meta:
db_table = '%s_relation' % model._meta.db_table
unique_together = (('tag', 'content_type', 'object_id'),)
return u'%s [%s]' % (self.content_type.get_object_for_this_type(pk=self.object_id), self.tag)
except ObjectDoesNotExist:
return u'<deleted> [%s]' % self.tag
-
- # Set up a dictionary to simulate declarations within a class
+
+ # Set up a dictionary to simulate declarations within a class
attrs = {
'__module__': model.__module__,
'Meta': Meta,
class TagBase(models.Model):
"""Abstract class to be inherited by model classes."""
__metaclass__ = TagMeta
-
+
class Meta:
abstract = True
-
+
@staticmethod
def get_tag_list(tag_list):
"""
Utility function for accepting tag input in a flexible manner.
-
+
You should probably override this method in your subclass.
"""
if isinstance(tag_list, TagBase):
fnp / wolnelektury.git / blobdiff