sexy draggable marquee

[wolnelektury.git] / apps / newtagging / models.py

diff --git a/apps/newtagging/models.py b/apps/newtagging/models.py
index b70ab9a..ea2a41f 100644 (file)
--- a/apps/newtagging/models.py
+++ b/apps/newtagging/models.py
@@ -6,7 +6,7 @@ Models and managers for generic tagging.
 # Python 2.3 compatibility
 try:
     set
 # Python 2.3 compatibility
 try:
     set

-except NameError: 
+except NameError:

     from sets import Set as set
 
 from django.contrib.contenttypes import generic
     from sets import Set as set
 
 from django.contrib.contenttypes import generic


@@ -15,6 +15,7 @@ from django.db import connection, models
 from django.utils.translation import ugettext_lazy as _
 from django.db.models.base import ModelBase
 from django.core.exceptions import ObjectDoesNotExist
 from django.utils.translation import ugettext_lazy as _
 from django.db.models.base import ModelBase
 from django.core.exceptions import ObjectDoesNotExist

+from django.dispatch import Signal

 
 qn = connection.ops.quote_name
 
 
 qn = connection.ops.quote_name
 


@@ -24,6 +25,8 @@ except ImportError:
     parse_lookup = None
 
 
     parse_lookup = None
 
 

+tags_updated = Signal(providing_args=["affected_tags"])
+

 def get_queryset_and_model(queryset_or_model):
     """
     Given a ``QuerySet`` or a ``Model``, returns a two-tuple of
 def get_queryset_and_model(queryset_or_model):
     """
     Given a ``QuerySet`` or a ``Model``, returns a two-tuple of


@@ -45,7 +48,17 @@ class TagManager(models.Manager):
     def __init__(self, intermediary_table_model):
         super(TagManager, self).__init__()
         self.intermediary_table_model = intermediary_table_model
     def __init__(self, intermediary_table_model):
         super(TagManager, self).__init__()
         self.intermediary_table_model = intermediary_table_model

-    
+        models.signals.pre_delete.connect(self.target_deleted)
+
+    def target_deleted(self, instance, **kwargs):
+        """ clear tag relations before deleting an object """
+        try:
+            int(instance.pk)
+        except ValueError:
+            return
+
+        self.update_tags(instance, [])
+

     def update_tags(self, obj, tags):
         """
         Update tags associated with an object.
     def update_tags(self, obj, tags):
         """
         Update tags associated with an object.


@@ -54,7 +67,7 @@ class TagManager(models.Manager):
         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)
         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]
         # Remove tags which no longer apply
         tags_for_removal = [tag for tag in current_tags \
                             if tag not in updated_tags]


@@ -63,10 +76,14 @@ class TagManager(models.Manager):
                                                object_id=obj.pk,
                                                tag__in=tags_for_removal).delete()
         # Add new tags
                                                object_id=obj.pk,
                                                tag__in=tags_for_removal).delete()
         # Add new tags

-        for tag in updated_tags:
+        tags_to_add = [tag for tag in updated_tags
+                       if tag not in current_tags]
+        for tag in tags_to_add:

             if tag not in current_tags:
                 self.intermediary_table_model._default_manager.create(tag=tag, content_object=obj)
             if tag not in current_tags:
                 self.intermediary_table_model._default_manager.create(tag=tag, content_object=obj)

-    
+
+        tags_updated.send(sender=obj, affected_tags=tags_to_add + tags_for_removal)
+

     def remove_tag(self, obj, tag):
         """
         Remove tag from an object.
     def remove_tag(self, obj, tag):
         """
         Remove tag from an object.


@@ -83,8 +100,8 @@ class TagManager(models.Manager):
         ctype = ContentType.objects.get_for_model(obj)
         return self.filter(items__content_type__pk=ctype.pk,
                            items__object_id=obj.pk)
         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``.
         """
         Perform the custom SQL query for ``usage_for_model`` and
         ``usage_for_queryset``.


@@ -94,25 +111,25 @@ class TagManager(models.Manager):
         model_table = qn(model._meta.db_table)
         model_pk = '%s.%s' % (model_table, qn(model._meta.pk.column))
         tag_columns = self._get_tag_columns()
         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'])
         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
         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
             INNER JOIN %(model)s

-                ON %(tagged_item_alias)s.object_id = %(model_pk)s
+                ON %(tagged_item)s.object_id = %(model_pk)s

             %%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
             %%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),
         %%s
         ORDER BY %(tag)s.%(ordering)s ASC""" % {
             'tag': qn(self.model._meta.db_table),


@@ -120,11 +137,9 @@ class TagManager(models.Manager):
             'tag_columns': tag_columns,
             'count_sql': counts and (', COUNT(%s)' % model_pk) or '',
             'tagged_item': qn(self.intermediary_table_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,
             '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,
         }
 
             'content_type_id': ContentType.objects.get_for_model(model).pk,
         }
 


@@ -202,12 +217,11 @@ class TagManager(models.Manager):
 
         extra_joins = ' '.join(queryset.query.get_from_clause()[0][1:])
         where, params = queryset.query.where.as_sql()
 
         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 = ''
         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):
         """
 
     def related_for_model(self, tags, model, counts=False, min_count=None, extra=None):
         """


@@ -227,12 +241,12 @@ class TagManager(models.Manager):
         tag_count = len(tags)
         tagged_item_table = qn(self.intermediary_table_model._meta.db_table)
         tag_columns = self._get_tag_columns()
         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'])
         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 = """
         # 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 = """


@@ -304,7 +318,7 @@ class TaggedItemManager(models.Manager):
     def __init__(self, tag_model):
         super(TaggedItemManager, self).__init__()
         self.tag_model = tag_model
     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 get_by_model(self, queryset_or_model, tags):
         """
         Create a ``QuerySet`` containing instances of the specified


@@ -476,7 +490,7 @@ class TaggedItemManager(models.Manager):
 def create_intermediary_table_model(model):
     """Create an intermediary table model for the specific tag model"""
     name = model.__name__ + 'Relation'
 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'),)
     class Meta:
         db_table = '%s_relation' % model._meta.db_table
         unique_together = (('tag', 'content_type', 'object_id'),)


@@ -486,8 +500,8 @@ def create_intermediary_table_model(model):
             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
             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,
     attrs = {
         '__module__': model.__module__,
         'Meta': Meta,


@@ -516,15 +530,15 @@ class TagMeta(ModelBase):
 class TagBase(models.Model):
     """Abstract class to be inherited by model classes."""
     __metaclass__ = TagMeta
 class TagBase(models.Model):
     """Abstract class to be inherited by model classes."""
     __metaclass__ = TagMeta

-    
+

     class Meta:
         abstract = True
     class Meta:
         abstract = True

-    
+

     @staticmethod
     def get_tag_list(tag_list):
         """
         Utility function for accepting tag input in a flexible manner.
     @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):
         You should probably override this method in your subclass.
         """
         if isinstance(tag_list, TagBase):