forum/models/node.py

   1 from base import *
   2 import re
   3 from tag import Tag
   4
   5 import markdown
   6 from django.utils.translation import ugettext as _
   7 from django.utils.safestring import mark_safe
   8 from django.utils.html import strip_tags
   9 from forum.utils.html import sanitize_html
  10 from utils import PickledObjectField
  11
  12 class NodeContent(models.Model):
  13     title      = models.CharField(max_length=300)
  14     tagnames   = models.CharField(max_length=125)
  15     author     = models.ForeignKey(User, related_name='%(class)ss')
  16     body       = models.TextField()
  17
  18     @property
  19     def user(self):
  20         return self.author
  21
  22     @property
  23     def html(self):
  24         return self.as_markdown()
  25
  26     @classmethod
  27     def _as_markdown(cls, content, *extensions):
  28         return mark_safe(sanitize_html(markdown.markdown(content, extensions=extensions)))
  29
  30     def as_markdown(self, *extensions):
  31         return self._as_markdown(self.body, *extensions)
  32
  33     @property
  34     def headline(self):
  35         return self.title
  36
  37     def tagname_list(self):
  38         if self.tagnames:
  39             t = [name.strip() for name in self.tagnames.split(u' ') if name]
  40             return [name.strip() for name in self.tagnames.split(u' ') if name]
  41         else:
  42             return []
  43
  44     def tagname_meta_generator(self):
  45         return u','.join([tag for tag in self.tagname_list()])
  46
  47     class Meta:
  48         abstract = True
  49         app_label = 'forum'
  50
  51 class NodeMetaClass(BaseMetaClass):
  52     types = {}
  53
  54     def __new__(cls, *args, **kwargs):
  55         new_cls = super(NodeMetaClass, cls).__new__(cls, *args, **kwargs)
  56
  57         if not new_cls._meta.abstract and new_cls.__name__ is not 'Node':
  58             NodeMetaClass.types[new_cls.get_type()] = new_cls
  59
  60         return new_cls
  61
  62     @classmethod
  63     def setup_relations(cls):
  64         for node_cls in NodeMetaClass.types.values():
  65             NodeMetaClass.setup_relation(node_cls)
  66
  67     @classmethod
  68     def setup_relation(cls, node_cls):
  69         name = node_cls.__name__.lower()
  70
  71         def children(self):
  72             return node_cls.objects.filter(parent=self)
  73
  74         def parent(self):
  75             p = self.__dict__.get('_%s_cache' % name, None)
  76
  77             if p is None and (self.parent is not None) and self.parent.node_type == name:
  78                 p = self.parent.leaf
  79                 self.__dict__['_%s_cache' % name] = p
  80
  81             return p
  82
  83         Node.add_to_class(name + 's', property(children))
  84         Node.add_to_class(name, property(parent))
  85
  86
  87 class NodeQuerySet(CachedQuerySet):
  88     def obj_from_datadict(self, datadict):
  89         cls = NodeMetaClass.types.get(datadict.get("node_type", ""), None)
  90         if cls:
  91             obj = cls()
  92             obj.__dict__.update(datadict)
  93             return obj
  94         else:
  95             return super(NodeQuerySet, self).obj_from_datadict(datadict)
  96
  97     def get(self, *args, **kwargs):
  98         node = super(NodeQuerySet, self).get(*args, **kwargs).leaf
  99
 100         if not isinstance(node, self.model):
 101             raise self.model.DoesNotExist()
 102
 103         return node
 104
 105     def filter_state(self, **kwargs):
 106         apply_bool = lambda q, b: b and q or ~q
 107         return self.filter(*[apply_bool(models.Q(state_string__contains="(%s)" % s), b) for s, b in kwargs.items()])
 108
 109
 110 class NodeManager(CachedManager):
 111     use_for_related_fields = True
 112
 113     def get_query_set(self):
 114         qs = NodeQuerySet(self.model)
 115
 116         if self.model is not Node:
 117             return qs.filter(node_type=self.model.get_type())
 118         else:
 119             return qs
 120
 121     def get_for_types(self, types, *args, **kwargs):
 122         kwargs['node_type__in'] = [t.get_type() for t in types]
 123         return self.get(*args, **kwargs)
 124
 125     def filter_state(self, **kwargs):
 126         return self.all().filter_state(**kwargs)
 127
 128
 129 class NodeStateDict(object):
 130     def __init__(self, node):
 131         self.__dict__['_node'] = node
 132
 133     def __getattr__(self, name):
 134         if self.__dict__.get(name, None):
 135             return self.__dict__[name]
 136
 137         try:
 138             node = self.__dict__['_node']
 139             action = NodeState.objects.get(node=node, state_type=name).action
 140             self.__dict__[name] = action
 141             return action
 142         except:
 143             return None
 144
 145     def __setattr__(self, name, value):
 146         current = self.__getattr__(name)
 147
 148         if value:
 149             if current:
 150                 current.action = value
 151                 current.save()
 152             else:
 153                 node = self.__dict__['_node']
 154                 state = NodeState(node=node, action=value, state_type=name)
 155                 state.save()
 156                 self.__dict__[name] = value
 157
 158                 if not "(%s)" % name in node.state_string:
 159                     node.state_string = "%s(%s)" % (node.state_string, name)
 160                     node.save()
 161         else:
 162             if current:
 163                 node = self.__dict__['_node']
 164                 node.state_string = "".join("(%s)" % s for s in re.findall('\w+', node.state_string) if s != name)
 165                 node.save()
 166                 current.node_state.delete()
 167                 del self.__dict__[name]
 168
 169
 170 class NodeStateQuery(object):
 171     def __init__(self, node):
 172         self.__dict__['_node'] = node
 173
 174     def __getattr__(self, name):
 175         node = self.__dict__['_node']
 176         return "(%s)" % name in node.state_string
 177
 178
 179 class Node(BaseModel, NodeContent):
 180     __metaclass__ = NodeMetaClass
 181
 182     node_type            = models.CharField(max_length=16, default='node')
 183     parent               = models.ForeignKey('Node', related_name='children', null=True)
 184     abs_parent           = models.ForeignKey('Node', related_name='all_children', null=True)
 185
 186     added_at             = models.DateTimeField(default=datetime.datetime.now)
 187     score                 = models.IntegerField(default=0)
 188
 189     state_string          = models.TextField(default='')
 190     last_edited           = models.ForeignKey('Action', null=True, unique=True, related_name="edited_node")
 191
 192     last_activity_by       = models.ForeignKey(User, null=True)
 193     last_activity_at       = models.DateTimeField(null=True, blank=True)
 194
 195     tags                 = models.ManyToManyField('Tag', related_name='%(class)ss')
 196     active_revision       = models.OneToOneField('NodeRevision', related_name='active', null=True)
 197
 198     extra = PickledObjectField()
 199     extra_ref = models.ForeignKey('Node', null=True)
 200     extra_count = models.IntegerField(default=0)
 201
 202     marked = models.BooleanField(default=False)
 203
 204     comment_count = DenormalizedField("children", node_type="comment", canceled=False)
 205     flag_count = DenormalizedField("flags")
 206
 207     friendly_name = _("post")
 208
 209     objects = NodeManager()
 210
 211     def __unicode__(self):
 212         return self.headline
 213
 214     @classmethod
 215     def _generate_cache_key(cls, key, group="node"):
 216         return super(Node, cls)._generate_cache_key(key, group)
 217
 218     @classmethod
 219     def get_type(cls):
 220         return cls.__name__.lower()
 221
 222     @property
 223     def leaf(self):
 224         leaf_cls = NodeMetaClass.types.get(self.node_type, None)
 225
 226         if leaf_cls is None:
 227             return self
 228
 229         leaf = leaf_cls()
 230         leaf.__dict__ = self.__dict__
 231         return leaf
 232
 233     @property
 234     def nstate(self):
 235         state = self.__dict__.get('_nstate', None)
 236
 237         if state is None:
 238             state = NodeStateDict(self)
 239             self._nstate = state
 240
 241         return state
 242
 243     @property
 244     def nis(self):
 245         nis = self.__dict__.get('_nis', None)
 246
 247         if nis is None:
 248             nis = NodeStateQuery(self)
 249             self._nis = nis
 250
 251         return nis
 252
 253     @property
 254     def deleted(self):
 255         return self.nis.deleted
 256
 257     @property
 258     def absolute_parent(self):
 259         if not self.abs_parent_id:
 260             return self
 261
 262         return self.abs_parent
 263
 264     @property
 265     def summary(self):
 266         return strip_tags(self.html)[:300]
 267
 268     @models.permalink
 269     def get_revisions_url(self):
 270         return ('revisions', (), {'id': self.id})
 271
 272     def update_last_activity(self, user, save=False):
 273         self.last_activity_by = user
 274         self.last_activity_at = datetime.datetime.now()
 275
 276         if self.parent:
 277             self.parent.update_last_activity(user, save=True)
 278
 279         if save:
 280             self.save()
 281
 282     def _create_revision(self, user, number, **kwargs):
 283         revision = NodeRevision(author=user, revision=number, node=self, **kwargs)
 284         revision.save()
 285         return revision
 286
 287     def create_revision(self, user, **kwargs):
 288         number = self.revisions.aggregate(last=models.Max('revision'))['last'] + 1
 289         revision = self._create_revision(user, number, **kwargs)
 290         self.activate_revision(user, revision)
 291         return revision
 292
 293     def activate_revision(self, user, revision):
 294         self.title = revision.title
 295         self.tagnames = revision.tagnames
 296         self.body = revision.body
 297
 298         self.active_revision = revision
 299         self.update_last_activity(user)
 300
 301         self.save()
 302
 303     def _list_changes_in_tags(self):
 304         dirty = self.get_dirty_fields()
 305
 306         if not 'tagnames' in dirty:
 307             return None
 308         else:
 309             if self._original_state['tagnames']:
 310                 old_tags = set(name for name in self._original_state['tagnames'].split(u' '))
 311             else:
 312                 old_tags = set()
 313             new_tags = set(name for name in self.tagnames.split(u' ') if name)
 314
 315             return dict(
 316                     current=list(new_tags),
 317                     added=list(new_tags - old_tags),
 318                     removed=list(old_tags - new_tags)
 319                     )
 320
 321     def _last_active_user(self):
 322         return self.last_edited and self.last_edited.by or self.author
 323
 324     def _process_changes_in_tags(self):
 325         tag_changes = self._list_changes_in_tags()
 326
 327         if tag_changes is not None:
 328             for name in tag_changes['added']:
 329                 try:
 330                     tag = Tag.objects.get(name=name)
 331                 except:
 332                     tag = Tag.objects.create(name=name, created_by=self._last_active_user())
 333
 334                 if not self.nis.deleted:
 335                     tag.add_to_usage_count(1)
 336                     tag.save()
 337
 338             if not self.nis.deleted:
 339                 for name in tag_changes['removed']:
 340                     try:
 341                         tag = Tag.objects.get(name=name)
 342                         tag.add_to_usage_count(-1)
 343                         tag.save()
 344                     except:
 345                         pass
 346
 347             return True
 348
 349         return False
 350
 351     def mark_deleted(self, action):
 352         self.nstate.deleted = action
 353         self.save()
 354
 355         if action:
 356             for tag in self.tags.all():
 357                 tag.add_to_usage_count(-1)
 358                 tag.save()
 359         else:
 360             for tag in Tag.objects.filter(name__in=self.tagname_list()):
 361                 tag.add_to_usage_count(1)
 362                 tag.save()
 363
 364     def save(self, *args, **kwargs):
 365         tags_changed = self._process_changes_in_tags()
 366
 367         if not self.id:
 368             self.node_type = self.get_type()
 369             super(BaseModel, self).save(*args, **kwargs)
 370             self.active_revision = self._create_revision(self.author, 1, title=self.title, tagnames=self.tagnames,
 371                                                          body=self.body)
 372             self.update_last_activity(self.author)
 373
 374         if self.parent_id and not self.abs_parent_id:
 375             self.abs_parent = self.parent.absolute_parent
 376
 377         super(Node, self).save(*args, **kwargs)
 378         if tags_changed: self.tags = list(Tag.objects.filter(name__in=self.tagname_list()))
 379
 380     class Meta:
 381         app_label = 'forum'
 382
 383
 384 class NodeRevision(BaseModel, NodeContent):
 385     node       = models.ForeignKey(Node, related_name='revisions')
 386     summary    = models.CharField(max_length=300)
 387     revision   = models.PositiveIntegerField()
 388     revised_at = models.DateTimeField(default=datetime.datetime.now)
 389
 390     class Meta:
 391         unique_together = ('node', 'revision')
 392         app_label = 'forum'
 393
 394
 395 class NodeState(models.Model):
 396     node       = models.ForeignKey(Node, related_name='states')
 397     state_type = models.CharField(max_length=16)
 398     action     = models.OneToOneField('Action', related_name="node_state")
 399
 400     class Meta:
 401         unique_together = ('node', 'state_type')
 402         app_label = 'forum'
 403
 404