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         try:
  29             return mark_safe(sanitize_html(markdown.markdown(content, extensions=extensions)))
  30         except Exception, e:
  31             import traceback
  32             logging.error("Caught exception %s in markdown parser rendering %s %s:\s %s" % (
  33                 str(e), cls.__name__, str(e), traceback.format_exc()))
  34             return ''
  35
  36     def as_markdown(self, *extensions):
  37         return self._as_markdown(self.body, *extensions)
  38
  39     @property
  40     def headline(self):
  41         return self.title
  42
  43     def tagname_list(self):
  44         if self.tagnames:
  45             t = [name.strip() for name in self.tagnames.split(u' ') if name]
  46             return [name.strip() for name in self.tagnames.split(u' ') if name]
  47         else:
  48             return []
  49
  50     def tagname_meta_generator(self):
  51         return u','.join([tag for tag in self.tagname_list()])
  52
  53     class Meta:
  54         abstract = True
  55         app_label = 'forum'
  56
  57 class NodeMetaClass(BaseMetaClass):
  58     types = {}
  59
  60     def __new__(cls, *args, **kwargs):
  61         new_cls = super(NodeMetaClass, cls).__new__(cls, *args, **kwargs)
  62
  63         if not new_cls._meta.abstract and new_cls.__name__ is not 'Node':
  64             NodeMetaClass.types[new_cls.get_type()] = new_cls
  65
  66         return new_cls
  67
  68     @classmethod
  69     def setup_relations(cls):
  70         for node_cls in NodeMetaClass.types.values():
  71             NodeMetaClass.setup_relation(node_cls)
  72
  73     @classmethod
  74     def setup_relation(cls, node_cls):
  75         name = node_cls.__name__.lower()
  76
  77         def children(self):
  78             return node_cls.objects.filter(parent=self)
  79
  80         def parent(self):
  81             p = self.__dict__.get('_%s_cache' % name, None)
  82
  83             if p is None and (self.parent is not None) and self.parent.node_type == name:
  84                 p = self.parent.leaf
  85                 self.__dict__['_%s_cache' % name] = p
  86
  87             return p
  88
  89         Node.add_to_class(name + 's', property(children))
  90         Node.add_to_class(name, property(parent))
  91
  92
  93 class NodeQuerySet(CachedQuerySet):
  94     def obj_from_datadict(self, datadict):
  95         cls = NodeMetaClass.types.get(datadict.get("node_type", ""), None)
  96         if cls:
  97             obj = cls()
  98             obj.__dict__.update(datadict)
  99             return obj
 100         else:
 101             return super(NodeQuerySet, self).obj_from_datadict(datadict)
 102
 103     def get(self, *args, **kwargs):
 104         node = super(NodeQuerySet, self).get(*args, **kwargs).leaf
 105
 106         if not isinstance(node, self.model):
 107             raise self.model.DoesNotExist()
 108
 109         return node
 110
 111     def any_state(self, *args):
 112         filter = None
 113
 114         for s in args:
 115             s_filter = models.Q(state_string__contains="(%s)" % s)
 116             filter = filter and (filter | s_filter) or s_filter
 117
 118         if filter:
 119             return self.filter(filter)
 120         else:
 121             return self
 122
 123     def all_states(self, *args):
 124         filter = None
 125
 126         for s in args:
 127             s_filter = models.Q(state_string__contains="(%s)" % s)
 128             filter = filter and (filter & s_filter) or s_filter
 129
 130         if filter:
 131             return self.filter(filter)
 132         else:
 133             return self
 134
 135     def filter_state(self, **kwargs):
 136         apply_bool = lambda q, b: b and q or ~q
 137         return self.filter(*[apply_bool(models.Q(state_string__contains="(%s)" % s), b) for s, b in kwargs.items()])
 138
 139     def children_count(self, child_type):
 140         return NodeMetaClass.types[child_type].objects.filter_state(deleted=False).filter(parent__in=self).count()
 141
 142
 143 class NodeManager(CachedManager):
 144     use_for_related_fields = True
 145
 146     def get_query_set(self):
 147         qs = NodeQuerySet(self.model)
 148
 149         if self.model is not Node:
 150             return qs.filter(node_type=self.model.get_type())
 151         else:
 152             return qs
 153
 154     def get_for_types(self, types, *args, **kwargs):
 155         kwargs['node_type__in'] = [t.get_type() for t in types]
 156         return self.get(*args, **kwargs)
 157
 158     def filter_state(self, **kwargs):
 159         return self.all().filter_state(**kwargs)
 160
 161
 162 class NodeStateDict(object):
 163     def __init__(self, node):
 164         self.__dict__['_node'] = node
 165
 166     def __getattr__(self, name):
 167         if self.__dict__.get(name, None):
 168             return self.__dict__[name]
 169
 170         try:
 171             node = self.__dict__['_node']
 172             action = NodeState.objects.get(node=node, state_type=name).action
 173             self.__dict__[name] = action
 174             return action
 175         except:
 176             return None
 177
 178     def __setattr__(self, name, value):
 179         current = self.__getattr__(name)
 180
 181         if value:
 182             if current:
 183                 current.action = value
 184                 current.save()
 185             else:
 186                 node = self.__dict__['_node']
 187                 state = NodeState(node=node, action=value, state_type=name)
 188                 state.save()
 189                 self.__dict__[name] = value
 190
 191                 if not "(%s)" % name in node.state_string:
 192                     node.state_string = "%s(%s)" % (node.state_string, name)
 193                     node.save()
 194         else:
 195             if current:
 196                 node = self.__dict__['_node']
 197                 node.state_string = "".join("(%s)" % s for s in re.findall('\w+', node.state_string) if s != name)
 198                 node.save()
 199                 current.node_state.delete()
 200                 del self.__dict__[name]
 201
 202
 203 class NodeStateQuery(object):
 204     def __init__(self, node):
 205         self.__dict__['_node'] = node
 206
 207     def __getattr__(self, name):
 208         node = self.__dict__['_node']
 209         return "(%s)" % name in node.state_string
 210
 211
 212 class Node(BaseModel, NodeContent):
 213     __metaclass__ = NodeMetaClass
 214
 215     node_type            = models.CharField(max_length=16, default='node')
 216     parent               = models.ForeignKey('Node', related_name='children', null=True)
 217     abs_parent           = models.ForeignKey('Node', related_name='all_children', null=True)
 218
 219     added_at             = models.DateTimeField(default=datetime.datetime.now)
 220     score                 = models.IntegerField(default=0)
 221
 222     state_string          = models.TextField(default='')
 223     last_edited           = models.ForeignKey('Action', null=True, unique=True, related_name="edited_node")
 224
 225     last_activity_by       = models.ForeignKey(User, null=True)
 226     last_activity_at       = models.DateTimeField(null=True, blank=True)
 227
 228     tags                 = models.ManyToManyField('Tag', related_name='%(class)ss')
 229     active_revision       = models.OneToOneField('NodeRevision', related_name='active', null=True)
 230
 231     extra = PickledObjectField()
 232     extra_ref = models.ForeignKey('Node', null=True)
 233     extra_count = models.IntegerField(default=0)
 234
 235     marked = models.BooleanField(default=False)
 236
 237     comment_count = DenormalizedField("children", node_type="comment", canceled=False)
 238     flag_count = DenormalizedField("flags")
 239
 240     friendly_name = _("post")
 241
 242     objects = NodeManager()
 243
 244     def __unicode__(self):
 245         return self.headline
 246
 247     @classmethod
 248     def _generate_cache_key(cls, key, group="node"):
 249         return super(Node, cls)._generate_cache_key(key, group)
 250
 251     @classmethod
 252     def get_type(cls):
 253         return cls.__name__.lower()
 254
 255     @property
 256     def leaf(self):
 257         leaf_cls = NodeMetaClass.types.get(self.node_type, None)
 258
 259         if leaf_cls is None:
 260             return self
 261
 262         leaf = leaf_cls()
 263         leaf.__dict__ = self.__dict__
 264         return leaf
 265
 266     @property
 267     def nstate(self):
 268         state = self.__dict__.get('_nstate', None)
 269
 270         if state is None:
 271             state = NodeStateDict(self)
 272             self._nstate = state
 273
 274         return state
 275
 276     @property
 277     def nis(self):
 278         nis = self.__dict__.get('_nis', None)
 279
 280         if nis is None:
 281             nis = NodeStateQuery(self)
 282             self._nis = nis
 283
 284         return nis
 285
 286     @property
 287     def state_list(self):
 288         return [s.state_type for s in self.states.all()]
 289
 290     @property
 291     def deleted(self):
 292         return self.nis.deleted
 293
 294     @property
 295     def absolute_parent(self):
 296         if not self.abs_parent_id:
 297             return self
 298
 299         return self.abs_parent
 300
 301     @property
 302     def summary(self):
 303         return strip_tags(self.html)[:300]
 304
 305     @models.permalink
 306     def get_revisions_url(self):
 307         return ('revisions', (), {'id': self.id})
 308
 309     def update_last_activity(self, user, save=False, time=None):
 310         if not time:
 311             time = datetime.datetime.now()
 312
 313         self.last_activity_by = user
 314         self.last_activity_at = time
 315
 316         if self.parent:
 317             self.parent.update_last_activity(user, save=True, time=time)
 318
 319         if save:
 320             self.save()
 321
 322     def _create_revision(self, user, number, **kwargs):
 323         revision = NodeRevision(author=user, revision=number, node=self, **kwargs)
 324         revision.save()
 325         return revision
 326
 327     def create_revision(self, user, **kwargs):
 328         number = self.revisions.aggregate(last=models.Max('revision'))['last'] + 1
 329         revision = self._create_revision(user, number, **kwargs)
 330         self.activate_revision(user, revision)
 331         return revision
 332
 333     def activate_revision(self, user, revision):
 334         self.title = revision.title
 335         self.tagnames = revision.tagnames
 336         self.body = revision.body
 337
 338         self.active_revision = revision
 339         self.update_last_activity(user)
 340
 341         self.save()
 342
 343     def _list_changes_in_tags(self):
 344         dirty = self.get_dirty_fields()
 345
 346         if not 'tagnames' in dirty:
 347             return None
 348         else:
 349             if self._original_state['tagnames']:
 350                 old_tags = set(name for name in self._original_state['tagnames'].split(u' '))
 351             else:
 352                 old_tags = set()
 353             new_tags = set(name for name in self.tagnames.split(u' ') if name)
 354
 355             return dict(
 356                     current=list(new_tags),
 357                     added=list(new_tags - old_tags),
 358                     removed=list(old_tags - new_tags)
 359                     )
 360
 361     def _last_active_user(self):
 362         return self.last_edited and self.last_edited.by or self.author
 363
 364     def _process_changes_in_tags(self):
 365         tag_changes = self._list_changes_in_tags()
 366
 367         if tag_changes is not None:
 368             for name in tag_changes['added']:
 369                 try:
 370                     tag = Tag.objects.get(name=name)
 371                 except:
 372                     tag = Tag.objects.create(name=name, created_by=self._last_active_user())
 373
 374                 if not self.nis.deleted:
 375                     tag.add_to_usage_count(1)
 376                     tag.save()
 377
 378             if not self.nis.deleted:
 379                 for name in tag_changes['removed']:
 380                     try:
 381                         tag = Tag.objects.get(name=name)
 382                         tag.add_to_usage_count(-1)
 383                         tag.save()
 384                     except:
 385                         pass
 386
 387             return True
 388
 389         return False
 390
 391     def mark_deleted(self, action):
 392         self.nstate.deleted = action
 393         self.save()
 394
 395         if action:
 396             for tag in self.tags.all():
 397                 tag.add_to_usage_count(-1)
 398                 tag.save()
 399         else:
 400             for tag in Tag.objects.filter(name__in=self.tagname_list()):
 401                 tag.add_to_usage_count(1)
 402                 tag.save()
 403
 404     def delete(self, *args, **kwargs):
 405         self.active_revision = None
 406         self.save()
 407
 408         for n in self.children.all():
 409             n.delete()
 410
 411         for a in self.actions.all():
 412             a.cancel()
 413
 414         super(Node, self).delete(*args, **kwargs)
 415
 416     def save(self, *args, **kwargs):
 417         tags_changed = self._process_changes_in_tags()
 418
 419         if not self.id:
 420             self.node_type = self.get_type()
 421             super(BaseModel, self).save(*args, **kwargs)
 422             self.active_revision = self._create_revision(self.author, 1, title=self.title, tagnames=self.tagnames,
 423                                                          body=self.body)
 424             self.update_last_activity(self.author, time=self.added_at)
 425
 426         if self.parent_id and not self.abs_parent_id:
 427             self.abs_parent = self.parent.absolute_parent
 428
 429         super(Node, self).save(*args, **kwargs)
 430         if tags_changed: self.tags = list(Tag.objects.filter(name__in=self.tagname_list()))
 431
 432     class Meta:
 433         app_label = 'forum'
 434
 435
 436 class NodeRevision(BaseModel, NodeContent):
 437     node       = models.ForeignKey(Node, related_name='revisions')
 438     summary    = models.CharField(max_length=300)
 439     revision   = models.PositiveIntegerField()
 440     revised_at = models.DateTimeField(default=datetime.datetime.now)
 441
 442     class Meta:
 443         unique_together = ('node', 'revision')
 444         app_label = 'forum'
 445
 446
 447 class NodeState(models.Model):
 448     node       = models.ForeignKey(Node, related_name='states')
 449     state_type = models.CharField(max_length=16)
 450     action     = models.OneToOneField('Action', related_name="node_state")
 451
 452     class Meta:
 453         unique_together = ('node', 'state_type')
 454         app_label = 'forum'
 455
 456