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 forum.utils.userlinking import auto_user_link
  11 from forum.settings import SUMMARY_LENGTH
  12 from utils import PickledObjectField
  13
  14 class NodeContent(models.Model):
  15     title      = models.CharField(max_length=300)
  16     tagnames   = models.CharField(max_length=125)
  17     author     = models.ForeignKey(User, related_name='%(class)ss')
  18     body       = models.TextField()
  19
  20     @property
  21     def user(self):
  22         return self.author
  23
  24     @property
  25     def html(self):
  26         return self.body
  27
  28     def rendered(self, content):
  29         return auto_user_link(self, self._as_markdown(content, *['auto_linker']))
  30
  31     @classmethod
  32     def _as_markdown(cls, content, *extensions):
  33         try:
  34             return mark_safe(sanitize_html(markdown.markdown(content, extensions=extensions)))
  35         except Exception, e:
  36             import traceback
  37             logging.error("Caught exception %s in markdown parser rendering %s %s:\s %s" % (
  38                 str(e), cls.__name__, str(e), traceback.format_exc()))
  39             return ''
  40
  41     def as_markdown(self, *extensions):
  42         return self._as_markdown(self.body, *extensions)
  43
  44     @property
  45     def headline(self):
  46         title = self.title
  47
  48         # Replaces multiple spaces with single ones.
  49         title = re.sub(' +',' ', title)
  50
  51         return title
  52
  53     def tagname_list(self):
  54         if self.tagnames:
  55             return [name.strip() for name in self.tagnames.split(u' ') if name]
  56         else:
  57             return []
  58
  59     def tagname_meta_generator(self):
  60         return u','.join([tag for tag in self.tagname_list()])
  61
  62     class Meta:
  63         abstract = True
  64         app_label = 'forum'
  65
  66 class NodeMetaClass(BaseMetaClass):
  67     types = {}
  68
  69     def __new__(cls, *args, **kwargs):
  70         new_cls = super(NodeMetaClass, cls).__new__(cls, *args, **kwargs)
  71
  72         if not new_cls._meta.abstract and new_cls.__name__ is not 'Node':
  73             NodeMetaClass.types[new_cls.get_type()] = new_cls
  74
  75         return new_cls
  76
  77     @classmethod
  78     def setup_relations(cls):
  79         for node_cls in NodeMetaClass.types.values():
  80             NodeMetaClass.setup_relation(node_cls)
  81
  82     @classmethod
  83     def setup_relation(cls, node_cls):
  84         name = node_cls.__name__.lower()
  85
  86         def children(self):
  87             return node_cls.objects.filter(parent=self)
  88
  89         def parent(self):
  90             if (self.parent is not None) and self.parent.node_type == name:
  91                 return self.parent.leaf
  92
  93             return None
  94
  95         Node.add_to_class(name + 's', property(children))
  96         Node.add_to_class(name, property(parent))
  97
  98
  99 class NodeQuerySet(CachedQuerySet):
 100     def obj_from_datadict(self, datadict):
 101         cls = NodeMetaClass.types.get(datadict.get("node_type", ""), None)
 102         if cls:
 103             obj = cls()
 104             obj.__dict__.update(datadict)
 105             return obj
 106         else:
 107             return super(NodeQuerySet, self).obj_from_datadict(datadict)
 108
 109     def get(self, *args, **kwargs):
 110         node = super(NodeQuerySet, self).get(*args, **kwargs).leaf
 111
 112         if not isinstance(node, self.model):
 113             raise self.model.DoesNotExist()
 114
 115         return node
 116
 117     def any_state(self, *args):
 118         filter = None
 119
 120         for s in args:
 121             s_filter = models.Q(state_string__contains="(%s)" % s)
 122             filter = filter and (filter | s_filter) or s_filter
 123
 124         if filter:
 125             return self.filter(filter)
 126         else:
 127             return self
 128
 129     def all_states(self, *args):
 130         filter = None
 131
 132         for s in args:
 133             s_filter = models.Q(state_string__contains="(%s)" % s)
 134             filter = filter and (filter & s_filter) or s_filter
 135
 136         if filter:
 137             return self.filter(filter)
 138         else:
 139             return self
 140
 141     def filter_state(self, **kwargs):
 142         apply_bool = lambda q, b: b and q or ~q
 143         return self.filter(*[apply_bool(models.Q(state_string__contains="(%s)" % s), b) for s, b in kwargs.items()])
 144
 145     def children_count(self, child_type):
 146         return NodeMetaClass.types[child_type].objects.filter_state(deleted=False).filter(parent__in=self).count()
 147
 148
 149 class NodeManager(CachedManager):
 150     use_for_related_fields = True
 151
 152     def get_query_set(self):
 153         qs = NodeQuerySet(self.model)
 154
 155         # If the node is an answer, question or comment we filter the Node model by type
 156         if self.model is not Node:
 157             qs = qs.filter(node_type=self.model.get_type())
 158
 159         return qs
 160
 161     def get_for_types(self, types, *args, **kwargs):
 162         kwargs['node_type__in'] = [t.get_type() for t in types]
 163         return self.get(*args, **kwargs)
 164
 165     def filter_state(self, **kwargs):
 166         return self.all().filter_state(**kwargs)
 167
 168
 169 class NodeStateDict(object):
 170     def __init__(self, node):
 171         self.__dict__['_node'] = node
 172
 173     def __getattr__(self, name):
 174         if self.__dict__.get(name, None):
 175             return self.__dict__[name]
 176
 177         try:
 178             node = self.__dict__['_node']
 179             action = NodeState.objects.get(node=node, state_type=name).action
 180             self.__dict__[name] = action
 181             return action
 182         except:
 183             return None
 184
 185     def __setattr__(self, name, value):
 186         current = self.__getattr__(name)
 187
 188         if value:
 189             if current:
 190                 current.action = value
 191                 current.save()
 192             else:
 193                 node = self.__dict__['_node']
 194                 state = NodeState(node=node, action=value, state_type=name)
 195                 state.save()
 196                 self.__dict__[name] = value
 197
 198                 if not "(%s)" % name in node.state_string:
 199                     node.state_string = "%s(%s)" % (node.state_string, name)
 200                     node.save()
 201         else:
 202             if current:
 203                 node = self.__dict__['_node']
 204                 node.state_string = "".join("(%s)" % s for s in re.findall('\w+', node.state_string) if s != name)
 205                 node.save()
 206                 current.node_state.delete()
 207                 del self.__dict__[name]
 208
 209
 210 class NodeStateQuery(object):
 211     def __init__(self, node):
 212         self.__dict__['_node'] = node
 213
 214     def __getattr__(self, name):
 215         node = self.__dict__['_node']
 216         return "(%s)" % name in node.state_string
 217
 218
 219 class Node(BaseModel, NodeContent):
 220     __metaclass__ = NodeMetaClass
 221
 222     node_type            = models.CharField(max_length=16, default='node')
 223     parent               = models.ForeignKey('Node', related_name='children', null=True)
 224     abs_parent           = models.ForeignKey('Node', related_name='all_children', null=True)
 225
 226     added_at             = models.DateTimeField(default=datetime.datetime.now)
 227     score                 = models.IntegerField(default=0)
 228
 229     state_string          = models.TextField(default='')
 230     last_edited           = models.ForeignKey('Action', null=True, unique=True, related_name="edited_node")
 231
 232     last_activity_by       = models.ForeignKey(User, null=True)
 233     last_activity_at       = models.DateTimeField(null=True, blank=True)
 234
 235     tags                 = models.ManyToManyField('Tag', related_name='%(class)ss')
 236     active_revision       = models.OneToOneField('NodeRevision', related_name='active', null=True)
 237
 238     extra = PickledObjectField()
 239     extra_ref = models.ForeignKey('Node', null=True)
 240     extra_count = models.IntegerField(default=0)
 241
 242     marked = models.BooleanField(default=False)
 243
 244     comment_count = DenormalizedField("children", node_type="comment", canceled=False)
 245     flag_count = DenormalizedField("flags")
 246
 247     friendly_name = _("post")
 248
 249     objects = NodeManager()
 250
 251     def __unicode__(self):
 252         return self.headline
 253
 254     @classmethod
 255     def _generate_cache_key(cls, key, group="node"):
 256         return super(Node, cls)._generate_cache_key(key, group)
 257
 258     @classmethod
 259     def get_type(cls):
 260         return cls.__name__.lower()
 261
 262     @property
 263     def leaf(self):
 264         leaf_cls = NodeMetaClass.types.get(self.node_type, None)
 265
 266         if leaf_cls is None:
 267             return self
 268
 269         leaf = leaf_cls()
 270         leaf.__dict__ = self.__dict__
 271         return leaf
 272
 273     @property
 274     def nstate(self):
 275         state = self.__dict__.get('_nstate', None)
 276
 277         if state is None:
 278             state = NodeStateDict(self)
 279             self._nstate = state
 280
 281         return state
 282
 283     @property
 284     def nis(self):
 285         nis = self.__dict__.get('_nis', None)
 286
 287         if nis is None:
 288             nis = NodeStateQuery(self)
 289             self._nis = nis
 290
 291         return nis
 292
 293     @property
 294     def last_activity(self):
 295         try:
 296             return self.actions.order_by('-action_date')[0].action_date
 297         except:
 298             return self.last_seen
 299
 300     @property
 301     def state_list(self):
 302         return [s.state_type for s in self.states.all()]
 303
 304     @property
 305     def deleted(self):
 306         return self.nis.deleted
 307
 308     @property
 309     def absolute_parent(self):
 310         if not self.abs_parent_id:
 311             return self
 312
 313         return self.abs_parent
 314
 315     @property
 316     def summary(self):
 317         content = strip_tags(self.html)[:SUMMARY_LENGTH]
 318
 319         # Remove multiple spaces.
 320         content = re.sub(' +',' ', content)
 321
 322         # Remove line breaks. We don't need them at all.
 323         content = content.replace("\n", '')
 324
 325         return content
 326
 327     @models.permalink
 328     def get_revisions_url(self):
 329         return ('revisions', (), {'id': self.id})
 330
 331     def update_last_activity(self, user, save=False, time=None):
 332         if not time:
 333             time = datetime.datetime.now()
 334
 335         self.last_activity_by = user
 336         self.last_activity_at = time
 337
 338         if self.parent:
 339             self.parent.update_last_activity(user, save=True, time=time)
 340
 341         if save:
 342             self.save()
 343
 344     def _create_revision(self, user, number, **kwargs):
 345         revision = NodeRevision(author=user, revision=number, node=self, **kwargs)
 346         revision.save()
 347         return revision
 348
 349     def create_revision(self, user, **kwargs):
 350         number = self.revisions.aggregate(last=models.Max('revision'))['last'] + 1
 351         revision = self._create_revision(user, number, **kwargs)
 352         self.activate_revision(user, revision)
 353         return revision
 354
 355     def activate_revision(self, user, revision):
 356         self.title = revision.title
 357         self.tagnames = revision.tagnames
 358
 359         self.body = self.rendered(revision.body)
 360
 361         self.active_revision = revision
 362         self.update_last_activity(user)
 363
 364         self.save()
 365
 366     def get_active_users(self, active_users = None):
 367         if not active_users:
 368             active_users = set()
 369
 370         active_users.add(self.author)
 371
 372         for node in self.children.all():
 373             if not node.nis.deleted:
 374                 node.get_active_users(active_users)
 375
 376         return active_users
 377
 378     def _list_changes_in_tags(self):
 379         dirty = self.get_dirty_fields()
 380
 381         if not 'tagnames' in dirty:
 382             return None
 383         else:
 384             if self._original_state['tagnames']:
 385                 old_tags = set(self._original_state['tagnames'].split())
 386             else:
 387                 old_tags = set()
 388             new_tags = set(self.tagnames.split())
 389
 390             return dict(
 391                     current=list(new_tags),
 392                     added=list(new_tags - old_tags),
 393                     removed=list(old_tags - new_tags)
 394                     )
 395
 396     def _last_active_user(self):
 397         return self.last_edited and self.last_edited.by or self.author
 398
 399     def _process_changes_in_tags(self):
 400         tag_changes = self._list_changes_in_tags()
 401
 402         if tag_changes is not None:
 403             for name in tag_changes['added']:
 404                 try:
 405                     tag = Tag.objects.get(name=name)
 406                 except Tag.DoesNotExist:
 407                     tag = Tag.objects.create(name=name, created_by=self._last_active_user())
 408
 409                 if not self.nis.deleted:
 410                     tag.add_to_usage_count(1)
 411                     tag.save()
 412
 413             if not self.nis.deleted:
 414                 for name in tag_changes['removed']:
 415                     try:
 416                         tag = Tag.objects.get(name=name)
 417                         tag.add_to_usage_count(-1)
 418                         tag.save()
 419                     except:
 420                         pass
 421
 422             return True
 423
 424         return False
 425
 426     def mark_deleted(self, action):
 427         self.nstate.deleted = action
 428         self.save()
 429
 430         if action:
 431             for tag in self.tags.all():
 432                 tag.add_to_usage_count(-1)
 433                 tag.save()
 434         else:
 435             for tag in Tag.objects.filter(name__in=self.tagname_list()):
 436                 tag.add_to_usage_count(1)
 437                 tag.save()
 438
 439     def delete(self, *args, **kwargs):
 440         for tag in self.tags.all():
 441             tag.add_to_usage_count(-1)
 442             tag.save()
 443
 444         self.active_revision = None
 445         self.save()
 446
 447         for n in self.children.all():
 448             n.delete()
 449
 450         for a in self.actions.all():
 451             a.cancel()
 452
 453         super(Node, self).delete(*args, **kwargs)
 454
 455     def save(self, *args, **kwargs):
 456         if not self.id:
 457             self.node_type = self.get_type()
 458             super(BaseModel, self).save(*args, **kwargs)
 459             self.active_revision = self._create_revision(self.author, 1, title=self.title, tagnames=self.tagnames,
 460                                                          body=self.body)
 461             self.activate_revision(self.author, self.active_revision)
 462             self.update_last_activity(self.author, time=self.added_at)
 463
 464         if self.parent_id and not self.abs_parent_id:
 465             self.abs_parent = self.parent.absolute_parent
 466
 467         tags_changed = self._process_changes_in_tags()
 468
 469         super(Node, self).save(*args, **kwargs)
 470         if tags_changed:
 471             self.tags = list(Tag.objects.filter(name__in=self.tagname_list()))
 472
 473     class Meta:
 474         app_label = 'forum'
 475
 476
 477 class NodeRevision(BaseModel, NodeContent):
 478     node       = models.ForeignKey(Node, related_name='revisions')
 479     summary    = models.CharField(max_length=300)
 480     revision   = models.PositiveIntegerField()
 481     revised_at = models.DateTimeField(default=datetime.datetime.now)
 482
 483     class Meta:
 484         unique_together = ('node', 'revision')
 485         app_label = 'forum'
 486
 487
 488 class NodeState(models.Model):
 489     node       = models.ForeignKey(Node, related_name='states')
 490     state_type = models.CharField(max_length=16)
 491     action     = models.OneToOneField('Action', related_name="node_state")
 492
 493     class Meta:
 494         unique_together = ('node', 'state_type')
 495         app_label = 'forum'
 496
 497