]> git.openstreetmap.org Git - osqa.git/blobdiff - forum/models/node.py
make RSS items decoratable, add an option to block email notifications per node,...
[osqa.git] / forum / models / node.py
index d2b70b6eeb099e6f207f18ca1f016c15fd79d585..387f8870b8525df3aca59e1b7319f0ff10b36ee9 100644 (file)
-from base import *\r
-from tag import Tag\r
-\r
-import markdown\r
-from django.utils.translation import ugettext as _\r
-from django.utils.safestring import mark_safe\r
-from django.utils.html import strip_tags\r
-from forum.utils.html import sanitize_html\r
-\r
-class NodeContent(models.Model):\r
-    title      = models.CharField(max_length=300)\r
-    tagnames   = models.CharField(max_length=125)\r
-    author     = models.ForeignKey(User, related_name='%(class)ss')\r
-    body       = models.TextField()\r
-\r
-    @property\r
-    def user(self):\r
-        return self.author\r
-\r
-    @property\r
-    def html(self):\r
-        return self.as_markdown()\r
-\r
-    def as_markdown(self, *extensions):\r
-        return mark_safe(sanitize_html(markdown.markdown(self.body, extensions=extensions)))\r
-\r
-    @property\r
-    def headline(self):\r
-        return self.title\r
-\r
-    def tagname_list(self):\r
-        if self.tagnames:\r
-            return [name for name in self.tagnames.split(u' ')]\r
-        else:\r
-            return []\r
-\r
-    def tagname_meta_generator(self):\r
-        return u','.join([unicode(tag) for tag in self.tagname_list()])\r
-\r
-    class Meta:\r
-        abstract = True\r
-        app_label = 'forum'\r
-\r
-class NodeMetaClass(BaseMetaClass):\r
-    types = {}\r
-\r
-    def __new__(cls, *args, **kwargs):\r
-        new_cls = super(NodeMetaClass, cls).__new__(cls, *args, **kwargs)\r
-\r
-        if not new_cls._meta.abstract and new_cls.__name__ is not 'Node':\r
-            NodeMetaClass.types[new_cls.get_type()] = new_cls\r
-\r
-        return new_cls\r
-\r
-    @classmethod\r
-    def setup_relations(cls):\r
-        for node_cls in NodeMetaClass.types.values():\r
-            NodeMetaClass.setup_relation(node_cls)        \r
-\r
-    @classmethod\r
-    def setup_relation(cls, node_cls):\r
-        name = node_cls.__name__.lower()\r
-\r
-        def children(self):\r
-            return node_cls.objects.filter(parent=self)\r
-\r
-        def parent(self):\r
-            p = self.__dict__.get('_%s_cache' % name, None)\r
-\r
-            if p is None and (self.parent is not None) and self.parent.node_type == name:\r
-                p = self.parent.leaf\r
-                self.__dict__['_%s_cache' % name] = p\r
-\r
-            return p\r
-\r
-        Node.add_to_class(name + 's', property(children))\r
-        Node.add_to_class(name, property(parent))\r
-\r
-\r
-class NodeManager(CachedManager):\r
-    use_for_related_fields = True\r
-\r
-    def get_query_set(self):\r
-        qs = super(NodeManager, self).get_query_set()\r
-\r
-        if self.model is not Node:\r
-            return qs.filter(node_type=self.model.get_type())\r
-        else:\r
-            return qs\r
-\r
-    def get(self, *args, **kwargs):\r
-        node = super(NodeManager, self).get(*args, **kwargs)\r
-        cls = NodeMetaClass.types.get(node.node_type, None)\r
-\r
-        if cls and node.__class__ is not cls:\r
-            return node.leaf\r
-        return node\r
-\r
-    def get_for_types(self, types, *args, **kwargs):\r
-        kwargs['node_type__in'] = [t.get_type() for t in types]\r
-        return self.get(*args, **kwargs)\r
-\r
-\r
-class Node(BaseModel, NodeContent):\r
-    __metaclass__ = NodeMetaClass\r
-\r
-    node_type            = models.CharField(max_length=16, default='node')\r
-    parent               = models.ForeignKey('Node', related_name='children', null=True)\r
-    abs_parent           = models.ForeignKey('Node', related_name='all_children', null=True)\r
-\r
-    added_at             = models.DateTimeField(default=datetime.datetime.now)\r
-    score                 = models.IntegerField(default=0)\r
-\r
-    deleted               = models.ForeignKey('Action', null=True, unique=True, related_name="deleted_node")\r
-    in_moderation         = models.ForeignKey('Action', null=True, unique=True, related_name="moderated_node")\r
-    last_edited           = models.ForeignKey('Action', null=True, unique=True, related_name="edited_node")\r
-\r
-    last_activity_by       = models.ForeignKey(User, null=True)\r
-    last_activity_at       = models.DateTimeField(null=True, blank=True)\r
-\r
-    tags                 = models.ManyToManyField('Tag', related_name='%(class)ss')\r
-    active_revision       = models.OneToOneField('NodeRevision', related_name='active', null=True)\r
-\r
-    extra_ref = models.ForeignKey('Node', null=True)\r
-    extra_count = models.IntegerField(default=0)\r
-    extra_action = models.ForeignKey('Action', null=True, related_name="extra_node")\r
-    \r
-    marked = models.BooleanField(default=False)\r
-    wiki = models.BooleanField(default=False)\r
-\r
-    comment_count = DenormalizedField("children", node_type="comment", canceled=False)\r
-    flag_count = DenormalizedField("flags")\r
-\r
-    friendly_name = _("post")\r
-\r
-    objects = NodeManager()\r
-\r
-    @classmethod\r
-    def cache_key(cls, pk):\r
-        return '%s.node:%s' % (settings.APP_URL, pk)\r
-\r
-    @classmethod\r
-    def get_type(cls):\r
-        return cls.__name__.lower()\r
-\r
-    @property\r
-    def leaf(self):\r
-        leaf_cls = NodeMetaClass.types.get(self.node_type, None)\r
-\r
-        if leaf_cls is None:\r
-            return self\r
-\r
-        leaf = leaf_cls()\r
-        leaf.__dict__ = self.__dict__\r
-        return leaf\r
-\r
-    @property    \r
-    def absolute_parent(self):\r
-        if not self.abs_parent_id:\r
-            return self.leaf\r
-\r
-        return self.abs_parent.leaf\r
-\r
-    @property\r
-    def summary(self):\r
-        return strip_tags(self.html)[:300]\r
-\r
-    @models.permalink\r
-    def get_revisions_url(self):\r
-        return ('revisions', (), {'id': self.id})\r
-\r
-    def update_last_activity(self, user, save=False):\r
-        self.last_activity_by = user\r
-        self.last_activity_at = datetime.datetime.now()\r
-\r
-        if self.parent:\r
-            self.parent.update_last_activity(user, save=True)\r
-\r
-        if save:\r
-            self.save()\r
-\r
-    def _create_revision(self, user, number, **kwargs):\r
-        revision = NodeRevision(author=user, revision=number, node=self, **kwargs)\r
-        revision.save()\r
-        return revision\r
-\r
-    def create_revision(self, user, **kwargs):\r
-        number = self.revisions.aggregate(last=models.Max('revision'))['last'] + 1\r
-        revision = self._create_revision(user, number, **kwargs)\r
-        self.activate_revision(user, revision)\r
-        return revision\r
-\r
-    def activate_revision(self, user, revision):\r
-        self.title = revision.title\r
-        self.tagnames = revision.tagnames\r
-        self.body = revision.body\r
-\r
-        self.active_revision = revision\r
-        self.update_last_activity(user)\r
-\r
-        self.save()\r
-\r
-    def get_tag_list_if_changed(self):\r
-        dirty = self.get_dirty_fields()\r
-        active_user = self.last_edited and self.last_edited.by or self.author\r
-\r
-        if 'tagnames' in dirty:\r
-            new_tags = self.tagname_list()\r
-            old_tags = dirty['tagnames']\r
-\r
-            if old_tags is None or not old_tags:\r
-                old_tags = []\r
-            else:\r
-                old_tags = [name for name in dirty['tagnames'].split(u' ')]\r
-\r
-            tag_list = []\r
-\r
-            for name in new_tags:\r
-                try:\r
-                    tag = Tag.objects.get(name=name)\r
-                except:\r
-                    tag = Tag.objects.create(name=name, created_by=active_user or self.author)\r
-\r
-                tag_list.append(tag)\r
-\r
-                if not name in old_tags:\r
-                    tag.used_count = tag.used_count + 1\r
-                    if tag.deleted:\r
-                        tag.unmark_deleted()\r
-                    tag.save()\r
-\r
-            for name in [n for n in old_tags if not n in new_tags]:\r
-                tag = Tag.objects.get(name=name)\r
-                tag.used_count = tag.used_count - 1\r
-                if tag.used_count == 0:\r
-                    tag.mark_deleted(active_user)\r
-                tag.save()\r
-\r
-            return tag_list\r
-\r
-        return None\r
-\r
-    def save(self, *args, **kwargs):\r
-        if not self.id:\r
-            self.node_type = self.get_type()\r
-            super(BaseModel, self).save(*args, **kwargs)\r
-            self.active_revision = self._create_revision(self.author, 1, title=self.title, tagnames=self.tagnames, body=self.body)\r
-            self.update_last_activity(self.author)\r
-\r
-        if self.parent_id and not self.abs_parent_id:\r
-            self.abs_parent = self.parent.absolute_parent\r
-        \r
-        tags = self.get_tag_list_if_changed()\r
-        super(Node, self).save(*args, **kwargs)\r
-        if tags is not None: self.tags = tags\r
-\r
-    @staticmethod\r
-    def isSpam(comment, data):\r
-        return False\r
-        #if not settings.WORDPRESS_API_KEY:\r
-        #    return False\r
-        #\r
-        #api = Akismet(settings.WORDPRESS_API_KEY, settings.APP_URL)\r
-        #return api.comment_check(comment, data)\r
-\r
-    class Meta:\r
-        app_label = 'forum'\r
-\r
-\r
-class NodeRevision(BaseModel, NodeContent):\r
-    node       = models.ForeignKey(Node, related_name='revisions')\r
-    summary    = models.CharField(max_length=300)\r
-    revision   = models.PositiveIntegerField()\r
-    revised_at = models.DateTimeField(default=datetime.datetime.now)\r
-\r
-    class Meta:\r
-        unique_together = ('node', 'revision')\r
-        app_label = 'forum'\r
-\r
-\r
+# -*- coding: utf-8 -*-
+
+from base import *
+import re
+from tag import Tag
+
+import markdown
+from django.utils.encoding import smart_unicode
+from django.utils.translation import ugettext as _
+from django.utils.safestring import mark_safe
+from django.utils.html import strip_tags
+from forum.utils.html import sanitize_html
+from forum.utils.userlinking import auto_user_link
+from forum.settings import SUMMARY_LENGTH
+from utils import PickledObjectField
+
+class NodeContent(models.Model):
+    title      = models.CharField(max_length=300)
+    tagnames   = models.CharField(max_length=125)
+    author     = models.ForeignKey(User, related_name='%(class)ss')
+    body       = models.TextField()
+
+    @property
+    def user(self):
+        return self.author
+
+    @property
+    def html(self):
+        return self.body
+
+    def rendered(self, content):
+        return auto_user_link(self, self._as_markdown(content, *['auto_linker']))
+
+    @classmethod
+    def _as_markdown(cls, content, *extensions):
+        try:
+            return mark_safe(sanitize_html(markdown.markdown(content, extensions=extensions)))
+        except Exception, e:
+            import traceback
+            logging.error("Caught exception %s in markdown parser rendering %s %s:\s %s" % (
+                str(e), cls.__name__, str(e), traceback.format_exc()))
+            return ''
+
+    def as_markdown(self, *extensions):
+        return self._as_markdown(smart_unicode(self.body), *extensions)
+
+    @property
+    def headline(self):
+        title = self.title
+
+        # Replaces multiple spaces with single ones.
+        title = re.sub(' +',' ', title)
+
+        return title
+
+    def tagname_list(self):
+        if self.tagnames:
+            return [name.strip() for name in self.tagnames.split() if name]
+        else:
+            return []
+
+    def tagname_meta_generator(self):
+        return u','.join([tag for tag in self.tagname_list()])
+
+    class Meta:
+        abstract = True
+        app_label = 'forum'
+
+class NodeMetaClass(BaseMetaClass):
+    types = {}
+
+    def __new__(cls, *args, **kwargs):
+        new_cls = super(NodeMetaClass, cls).__new__(cls, *args, **kwargs)
+
+        if not new_cls._meta.abstract and new_cls.__name__ is not 'Node':
+            NodeMetaClass.types[new_cls.get_type()] = new_cls
+
+        return new_cls
+
+    @classmethod
+    def setup_relations(cls):
+        for node_cls in NodeMetaClass.types.values():
+            NodeMetaClass.setup_relation(node_cls)
+
+    @classmethod
+    def setup_relation(cls, node_cls):
+        name = node_cls.__name__.lower()
+
+        def children(self):
+            return node_cls.objects.filter(parent=self)
+
+        def parent(self):
+            if (self.parent is not None) and self.parent.node_type == name:
+                return self.parent.leaf
+
+            return None
+
+        Node.add_to_class(name + 's', property(children))
+        Node.add_to_class(name, property(parent))
+
+
+class NodeQuerySet(CachedQuerySet):
+    def obj_from_datadict(self, datadict):
+        cls = NodeMetaClass.types.get(datadict.get("node_type", ""), None)
+        if cls:
+            obj = cls()
+            obj.__dict__.update(datadict)
+            return obj
+        else:
+            return super(NodeQuerySet, self).obj_from_datadict(datadict)
+
+    def get(self, *args, **kwargs):
+        node = super(NodeQuerySet, self).get(*args, **kwargs).leaf
+
+        if not isinstance(node, self.model):
+            raise self.model.DoesNotExist()
+
+        return node
+
+    def any_state(self, *args):
+        filter = None
+
+        for s in args:
+            s_filter = models.Q(state_string__contains="(%s)" % s)
+            filter = filter and (filter | s_filter) or s_filter
+
+        if filter:
+            return self.filter(filter)
+        else:
+            return self
+
+    def all_states(self, *args):
+        filter = None
+
+        for s in args:
+            s_filter = models.Q(state_string__contains="(%s)" % s)
+            filter = filter and (filter & s_filter) or s_filter
+
+        if filter:
+            return self.filter(filter)
+        else:
+            return self
+
+    def filter_state(self, **kwargs):
+        apply_bool = lambda q, b: b and q or ~q
+        return self.filter(*[apply_bool(models.Q(state_string__contains="(%s)" % s), b) for s, b in kwargs.items()])
+
+    def children_count(self, child_type):
+        return NodeMetaClass.types[child_type].objects.filter_state(deleted=False).filter(parent__in=self).count()
+
+
+class NodeManager(CachedManager):
+    use_for_related_fields = True
+
+    def get_query_set(self):
+        qs = NodeQuerySet(self.model)
+
+        # If the node is an answer, question or comment we filter the Node model by type
+        if self.model is not Node:
+            qs = qs.filter(node_type=self.model.get_type())
+
+        return qs
+
+    def get_for_types(self, types, *args, **kwargs):
+        kwargs['node_type__in'] = [t.get_type() for t in types]
+        return self.get(*args, **kwargs)
+
+    def filter_state(self, **kwargs):
+        return self.all().filter_state(**kwargs)
+
+
+class NodeStateDict(object):
+    def __init__(self, node):
+        self.__dict__['_node'] = node
+
+    def __getattr__(self, name):
+        if self.__dict__.get(name, None):
+            return self.__dict__[name]
+
+        try:
+            node = self.__dict__['_node']
+            action = NodeState.objects.get(node=node, state_type=name).action
+            self.__dict__[name] = action
+            return action
+        except:
+            return None
+
+    def __setattr__(self, name, value):
+        current = self.__getattr__(name)
+
+        if value:
+            if current:
+                current.action = value
+                current.save()
+            else:
+                node = self.__dict__['_node']
+                state = NodeState(node=node, action=value, state_type=name)
+                state.save()
+                self.__dict__[name] = value
+
+                if not "(%s)" % name in node.state_string:
+                    node.state_string = "%s(%s)" % (node.state_string, name)
+                    node.save()
+        else:
+            if current:
+                node = self.__dict__['_node']
+                node.state_string = "".join("(%s)" % s for s in re.findall('\w+', node.state_string) if s != name)
+                node.save()
+                current.node_state.delete()
+                del self.__dict__[name]
+
+
+class NodeStateQuery(object):
+    def __init__(self, node):
+        self.__dict__['_node'] = node
+
+    def __getattr__(self, name):
+        node = self.__dict__['_node']
+        return "(%s)" % name in node.state_string
+
+
+class Node(BaseModel, NodeContent):
+    __metaclass__ = NodeMetaClass
+
+    node_type            = models.CharField(max_length=16, default='node')
+    parent               = models.ForeignKey('Node', related_name='children', null=True)
+    abs_parent           = models.ForeignKey('Node', related_name='all_children', null=True)
+
+    added_at             = models.DateTimeField(default=datetime.datetime.now)
+    score                 = models.IntegerField(default=0)
+
+    state_string          = models.TextField(default='')
+    last_edited           = models.ForeignKey('Action', null=True, unique=True, related_name="edited_node")
+
+    last_activity_by       = models.ForeignKey(User, null=True)
+    last_activity_at       = models.DateTimeField(null=True, blank=True)
+
+    tags                 = models.ManyToManyField('Tag', related_name='%(class)ss')
+    active_revision       = models.OneToOneField('NodeRevision', related_name='active', null=True)
+
+    extra = PickledObjectField()
+    extra_ref = models.ForeignKey('Node', null=True)
+    extra_count = models.IntegerField(default=0)
+
+    marked = models.BooleanField(default=False)
+
+    comment_count = DenormalizedField("children", node_type="comment", canceled=False)
+    flag_count = DenormalizedField("actions", action_type="flag", canceled=False)
+
+    friendly_name = _("post")
+
+    objects = NodeManager()
+
+    def __unicode__(self):
+        return self.headline
+
+    @classmethod
+    def _generate_cache_key(cls, key, group="node"):
+        return super(Node, cls)._generate_cache_key(key, group)
+        
+    @classmethod
+    def get_type(cls):
+        return cls.__name__.lower()
+
+    @property
+    def leaf(self):
+        leaf_cls = NodeMetaClass.types.get(self.node_type, None)
+
+        if leaf_cls is None:
+            return self
+
+        leaf = leaf_cls()
+        leaf.__dict__ = self.__dict__
+        return leaf
+
+    @property
+    def nstate(self):
+        state = self.__dict__.get('_nstate', None)
+
+        if state is None:
+            state = NodeStateDict(self)
+            self._nstate = state
+
+        return state
+
+    @property
+    def nis(self):
+        nis = self.__dict__.get('_nis', None)
+
+        if nis is None:
+            nis = NodeStateQuery(self)
+            self._nis = nis
+
+        return nis
+
+    @property
+    def last_activity(self):
+        try:
+            return self.actions.order_by('-action_date')[0].action_date
+        except:
+            return self.last_seen
+
+    @property
+    def state_list(self):
+        return [s.state_type for s in self.states.all()]
+
+    @property
+    def deleted(self):
+        return self.nis.deleted
+
+    @property
+    def absolute_parent(self):
+        if not self.abs_parent_id:
+            return self
+
+        return self.abs_parent
+
+    @property
+    def summary(self):
+        content = strip_tags(self.html)
+
+        # Remove multiple spaces.
+        content = re.sub(' +',' ', content)
+
+        # Replace line breaks with a space, we don't need them at all.
+        content = content.replace("\n", ' ')
+
+        # Truncate and all an ellipsis if length greater than summary length.
+        content = (content[:SUMMARY_LENGTH] + '...') if len(content) > SUMMARY_LENGTH else content
+
+        return content
+
+    # Can be used to block subscription notifications for a specific node from a module
+    def _is_notifiable(self):
+        return True
+
+    @property
+    def is_notifiable(self):
+        return self._is_notifiable()
+
+    @models.permalink
+    def get_revisions_url(self):
+        return ('revisions', (), {'id': self.id})
+
+    def update_last_activity(self, user, save=False, time=None):
+        if not time:
+            time = datetime.datetime.now()
+
+        self.last_activity_by = user
+        self.last_activity_at = time
+
+        if self.parent:
+            self.parent.update_last_activity(user, save=True, time=time)
+
+        if save:
+            self.save()
+
+    def _create_revision(self, user, number, **kwargs):
+        revision = NodeRevision(author=user, revision=number, node=self, **kwargs)
+        revision.save()
+        return revision
+
+    def create_revision(self, user, **kwargs):
+        number = self.revisions.aggregate(last=models.Max('revision'))['last'] + 1
+        revision = self._create_revision(user, number, **kwargs)
+        self.activate_revision(user, revision)
+        return revision
+
+    def activate_revision(self, user, revision):
+        self.title = revision.title
+        self.tagnames = revision.tagnames
+
+        self.body = self.rendered(revision.body)
+
+        self.active_revision = revision
+
+        # Try getting the previous revision
+        try:
+            prev_revision = NodeRevision.objects.get(node=self, revision=revision.revision-1)
+
+            update_activity = True
+
+            # Do not update the activity if only the tags are changed
+            if prev_revision.title == revision.title and prev_revision.body == revision.body \
+            and prev_revision.tagnames != revision.tagnames and not settings.UPDATE_LATEST_ACTIVITY_ON_TAG_EDIT:
+                update_activity = False
+        except NodeRevision.DoesNotExist:
+            update_activity = True
+        finally:
+            if update_activity:
+                self.update_last_activity(user)
+
+        self.save()
+
+    def get_active_users(self, active_users = None):
+        if not active_users:
+            active_users = set()
+
+        active_users.add(self.author)
+
+        for node in self.children.all():
+            if not node.nis.deleted:
+                node.get_active_users(active_users)
+
+        return active_users
+
+    def get_last_edited(self):
+        if not self.last_edited:
+            try:
+                le = self.actions.exclude(action_type__in=('voteup', 'votedown', 'flag'), canceled=True).order_by('-action_date')[0]
+                self.last_edited = le
+                self.save()
+            except:
+                pass
+
+        return self.last_edited
+
+
+    def _list_changes_in_tags(self):
+        dirty = self.get_dirty_fields()
+
+        if not 'tagnames' in dirty:
+            return None
+        else:
+            if self._original_state['tagnames']:
+                old_tags = set(self._original_state['tagnames'].split())
+            else:
+                old_tags = set()
+            new_tags = set(self.tagnames.split())
+
+            return dict(
+                    current=list(new_tags),
+                    added=list(new_tags - old_tags),
+                    removed=list(old_tags - new_tags)
+                    )
+
+    def _last_active_user(self):
+        return self.last_edited and self.last_edited.by or self.author
+
+    def _process_changes_in_tags(self):
+        tag_changes = self._list_changes_in_tags()
+
+        if tag_changes is not None:
+            for name in tag_changes['added']:
+                try:
+                    tag = Tag.objects.get(name=name)
+                except Tag.DoesNotExist:
+                    tag = Tag.objects.create(name=name, created_by=self._last_active_user())
+
+                if not self.nis.deleted:
+                    tag.add_to_usage_count(1)
+                    tag.save()
+
+            if not self.nis.deleted:
+                for name in tag_changes['removed']:
+                    try:
+                        tag = Tag.objects.get(name=name)
+                        tag.add_to_usage_count(-1)
+                        tag.save()
+                    except:
+                        pass
+
+            return True
+
+        return False
+
+    def mark_deleted(self, action):
+        self.nstate.deleted = action
+        self.save()
+
+        if action:
+            for tag in self.tags.all():
+                tag.add_to_usage_count(-1)
+                tag.save()
+        else:
+            for tag in Tag.objects.filter(name__in=self.tagname_list()):
+                tag.add_to_usage_count(1)
+                tag.save()
+
+    def delete(self, *args, **kwargs):
+        for tag in self.tags.all():
+            tag.add_to_usage_count(-1)
+            tag.save()
+
+        self.active_revision = None
+        self.save()
+
+        for n in self.children.all():
+            n.delete()
+
+        for a in self.actions.all():
+            a.cancel()
+
+        super(Node, self).delete(*args, **kwargs)
+
+    def save(self, *args, **kwargs):
+        if not self.id:
+            self.node_type = self.get_type()
+            super(BaseModel, self).save(*args, **kwargs)
+            self.active_revision = self._create_revision(self.author, 1, title=self.title, tagnames=self.tagnames,
+                                                         body=self.body)
+            self.activate_revision(self.author, self.active_revision)
+            self.update_last_activity(self.author, time=self.added_at)
+
+        if self.parent_id and not self.abs_parent_id:
+            self.abs_parent = self.parent.absolute_parent
+        
+        tags_changed = self._process_changes_in_tags()
+        
+        super(Node, self).save(*args, **kwargs)
+        if tags_changed:
+            if self.tagnames.strip():
+                self.tags = list(Tag.objects.filter(name__in=self.tagname_list()))
+            else:
+                self.tags = []
+
+    class Meta:
+        app_label = 'forum'
+
+
+class NodeRevision(BaseModel, NodeContent):
+    node       = models.ForeignKey(Node, related_name='revisions')
+    summary    = models.CharField(max_length=300)
+    revision   = models.PositiveIntegerField()
+    revised_at = models.DateTimeField(default=datetime.datetime.now)
+
+    class Meta:
+        unique_together = ('node', 'revision')
+        app_label = 'forum'
+
+
+class NodeState(models.Model):
+    node       = models.ForeignKey(Node, related_name='states')
+    state_type = models.CharField(max_length=16)
+    action     = models.OneToOneField('Action', related_name="node_state")
+
+    class Meta:
+        unique_together = ('node', 'state_type')
+        app_label = 'forum'
+
+