Add document methods to attach and remove tags

Signed-off-by: Roberto Rosario <Roberto.Rosario@mayan-edms.com>

mayan/apps/tags/methods.py

@@ -1,21 +1,48 @@
 from __future__ import unicode_literals
 
 from django.apps import apps
+from django.db import transaction
 from django.utils.translation import ugettext_lazy as _
 
+from .events import event_tag_attach, event_tag_remove
 from .permissions import permission_tag_view
 
 
-def method_get_tags(self, permission, user):
+def method_document_tags_attach(self, queryset, _user=None):
+    """
+    Attach a document to a tag and commit the corresponding event.
+    """
+    with transaction.atomic():
+        for tag in queryset:
+            self.tags.add(tag)
+            event_tag_attach.commit(
+                action_object=tag, actor=_user, target=self
+            )
+
+
+def method_document_get_tags(self, permission, user):
     AccessControlList = apps.get_model(
         app_label='acls', model_name='AccessControlList'
     )
     DocumentTag = apps.get_model(app_label='tags', model_name='DocumentTag')
+
     return AccessControlList.objects.restrict_queryset(
         permission=permission,
         queryset=DocumentTag.objects.filter(documents=self), user=user
     )
 
 
-method_get_tags.help_text = _('Return a the tags attached to the document.')
-method_get_tags.short_description = _('get_tags()')
+method_document_get_tags.help_text = _('Return a the tags attached to the document.')
+method_document_get_tags.short_description = _('get_tags()')
+
+
+def method_document_tags_remove(self, queryset, _user=None):
+    """
+    Remove a document from a tag and commit the corresponding event.
+    """
+    with transaction.atomic():
+        for tag in queryset:
+            self.tags.remove(tag)
+            event_tag_remove.commit(
+                action_object=tag, actor=_user, target=self
+            )