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 filter_state(self, **kwargs):
 112         apply_bool = lambda q, b: b and q or ~q
 113         return self.filter(*[apply_bool(models.Q(state_string__contains="(%s)" % s), b) for s, b in kwargs.items()])
 114
 115     def children_count(self, child_type):
 116         return NodeMetaClass.types[child_type].objects.filter_state(deleted=False).filter(parent__in=self).count()
 117
 118
 119 class NodeManager(CachedManager):
 120     use_for_related_fields = True
 121
 122     def get_query_set(self):
 123         qs = NodeQuerySet(self.model)
 124
 125         if self.model is not Node:
 126             return qs.filter(node_type=self.model.get_type())
 127         else:
 128             return qs
 129
 130     def get_for_types(self, types, *args, **kwargs):
 131         kwargs['node_type__in'] = [t.get_type() for t in types]
 132         return self.get(*args, **kwargs)
 133
 134     def filter_state(self, **kwargs):
 135         return self.all().filter_state(**kwargs)
 136
 137
 138 class NodeStateDict(object):
 139     def __init__(self, node):
 140         self.__dict__['_node'] = node
 141
 142     def __getattr__(self, name):
 143         if self.__dict__.get(name, None):
 144             return self.__dict__[name]
 145
 146         try:
 147             node = self.__dict__['_node']
 148             action = NodeState.objects.get(node=node, state_type=name).action
 149             self.__dict__[name] = action
 150             return action
 151         except:
 152             return None
 153
 154     def __setattr__(self, name, value):
 155         current = self.__getattr__(name)
 156
 157         if value:
 158             if current:
 159                 current.action = value
 160                 current.save()
 161             else:
 162                 node = self.__dict__['_node']
 163                 state = NodeState(node=node, action=value, state_type=name)
 164                 state.save()
 165                 self.__dict__[name] = value
 166
 167                 if not "(%s)" % name in node.state_string:
 168                     node.state_string = "%s(%s)" % (node.state_string, name)
 169                     node.save()
 170         else:
 171             if current:
 172                 node = self.__dict__['_node']
 173                 node.state_string = "".join("(%s)" % s for s in re.findall('\w+', node.state_string) if s != name)
 174                 node.save()
 175                 current.node_state.delete()
 176                 del self.__dict__[name]
 177
 178
 179 class NodeStateQuery(object):
 180     def __init__(self, node):
 181         self.__dict__['_node'] = node
 182
 183     def __getattr__(self, name):
 184         node = self.__dict__['_node']
 185         return "(%s)" % name in node.state_string
 186
 187
 188 class Node(BaseModel, NodeContent):
 189     __metaclass__ = NodeMetaClass
 190
 191     node_type            = models.CharField(max_length=16, default='node')
 192     parent               = models.ForeignKey('Node', related_name='children', null=True)
 193     abs_parent           = models.ForeignKey('Node', related_name='all_children', null=True)
 194
 195     added_at             = models.DateTimeField(default=datetime.datetime.now)
 196     score                 = models.IntegerField(default=0)
 197
 198     state_string          = models.TextField(default='')
 199     last_edited           = models.ForeignKey('Action', null=True, unique=True, related_name="edited_node")
 200
 201     last_activity_by       = models.ForeignKey(User, null=True)
 202     last_activity_at       = models.DateTimeField(null=True, blank=True)
 203
 204     tags                 = models.ManyToManyField('Tag', related_name='%(class)ss')
 205     active_revision       = models.OneToOneField('NodeRevision', related_name='active', null=True)
 206
 207     extra = PickledObjectField()
 208     extra_ref = models.ForeignKey('Node', null=True)
 209     extra_count = models.IntegerField(default=0)
 210
 211     marked = models.BooleanField(default=False)
 212
 213     comment_count = DenormalizedField("children", node_type="comment", canceled=False)
 214     flag_count = DenormalizedField("flags")
 215
 216     friendly_name = _("post")
 217
 218     objects = NodeManager()
 219
 220     def __unicode__(self):
 221         return self.headline
 222
 223     @classmethod
 224     def _generate_cache_key(cls, key, group="node"):
 225         return super(Node, cls)._generate_cache_key(key, group)
 226
 227     @classmethod
 228     def get_type(cls):
 229         return cls.__name__.lower()
 230
 231     @property
 232     def leaf(self):
 233         leaf_cls = NodeMetaClass.types.get(self.node_type, None)
 234
 235         if leaf_cls is None:
 236             return self
 237
 238         leaf = leaf_cls()
 239         leaf.__dict__ = self.__dict__
 240         return leaf
 241
 242     @property
 243     def nstate(self):
 244         state = self.__dict__.get('_nstate', None)
 245
 246         if state is None:
 247             state = NodeStateDict(self)
 248             self._nstate = state
 249
 250         return state
 251
 252     @property
 253     def nis(self):
 254         nis = self.__dict__.get('_nis', None)
 255
 256         if nis is None:
 257             nis = NodeStateQuery(self)
 258             self._nis = nis
 259
 260         return nis
 261
 262     @property
 263     def deleted(self):
 264         return self.nis.deleted
 265
 266     @property
 267     def absolute_parent(self):
 268         if not self.abs_parent_id:
 269             return self
 270
 271         return self.abs_parent
 272
 273     @property
 274     def summary(self):
 275         return strip_tags(self.html)[:300]
 276
 277     @models.permalink
 278     def get_revisions_url(self):
 279         return ('revisions', (), {'id': self.id})
 280
 281     def update_last_activity(self, user, save=False, time=None):
 282         if not time:
 283             time = datetime.datetime.now()
 284
 285         self.last_activity_by = user
 286         self.last_activity_at = time
 287
 288         if self.parent:
 289             self.parent.update_last_activity(user, save=True, time=time)
 290
 291         if save:
 292             self.save()
 293
 294     def _create_revision(self, user, number, **kwargs):
 295         revision = NodeRevision(author=user, revision=number, node=self, **kwargs)
 296         revision.save()
 297         return revision
 298
 299     def create_revision(self, user, **kwargs):
 300         number = self.revisions.aggregate(last=models.Max('revision'))['last'] + 1
 301         revision = self._create_revision(user, number, **kwargs)
 302         self.activate_revision(user, revision)
 303         return revision
 304
 305     def activate_revision(self, user, revision):
 306         self.title = revision.title
 307         self.tagnames = revision.tagnames
 308         self.body = revision.body
 309
 310         self.active_revision = revision
 311         self.update_last_activity(user)
 312
 313         self.save()
 314
 315     def _list_changes_in_tags(self):
 316         dirty = self.get_dirty_fields()
 317
 318         if not 'tagnames' in dirty:
 319             return None
 320         else:
 321             if self._original_state['tagnames']:
 322                 old_tags = set(name for name in self._original_state['tagnames'].split(u' '))
 323             else:
 324                 old_tags = set()
 325             new_tags = set(name for name in self.tagnames.split(u' ') if name)
 326
 327             return dict(
 328                     current=list(new_tags),
 329                     added=list(new_tags - old_tags),
 330                     removed=list(old_tags - new_tags)
 331                     )
 332
 333     def _last_active_user(self):
 334         return self.last_edited and self.last_edited.by or self.author
 335
 336     def _process_changes_in_tags(self):
 337         tag_changes = self._list_changes_in_tags()
 338
 339         if tag_changes is not None:
 340             for name in tag_changes['added']:
 341                 try:
 342                     tag = Tag.objects.get(name=name)
 343                 except:
 344                     tag = Tag.objects.create(name=name, created_by=self._last_active_user())
 345
 346                 if not self.nis.deleted:
 347                     tag.add_to_usage_count(1)
 348                     tag.save()
 349
 350             if not self.nis.deleted:
 351                 for name in tag_changes['removed']:
 352                     try:
 353                         tag = Tag.objects.get(name=name)
 354                         tag.add_to_usage_count(-1)
 355                         tag.save()
 356                     except:
 357                         pass
 358
 359             return True
 360
 361         return False
 362
 363     def mark_deleted(self, action):
 364         self.nstate.deleted = action
 365         self.save()
 366
 367         if action:
 368             for tag in self.tags.all():
 369                 tag.add_to_usage_count(-1)
 370                 tag.save()
 371         else:
 372             for tag in Tag.objects.filter(name__in=self.tagname_list()):
 373                 tag.add_to_usage_count(1)
 374                 tag.save()
 375
 376     def save(self, *args, **kwargs):
 377         tags_changed = self._process_changes_in_tags()
 378
 379         if not self.id:
 380             self.node_type = self.get_type()
 381             super(BaseModel, self).save(*args, **kwargs)
 382             self.active_revision = self._create_revision(self.author, 1, title=self.title, tagnames=self.tagnames,
 383                                                          body=self.body)
 384             self.update_last_activity(self.author, time=self.added_at)
 385
 386         if self.parent_id and not self.abs_parent_id:
 387             self.abs_parent = self.parent.absolute_parent
 388
 389         super(Node, self).save(*args, **kwargs)
 390         if tags_changed: self.tags = list(Tag.objects.filter(name__in=self.tagname_list()))
 391
 392     class Meta:
 393         app_label = 'forum'
 394
 395
 396 class NodeRevision(BaseModel, NodeContent):
 397     node       = models.ForeignKey(Node, related_name='revisions')
 398     summary    = models.CharField(max_length=300)
 399     revision   = models.PositiveIntegerField()
 400     revised_at = models.DateTimeField(default=datetime.datetime.now)
 401
 402     class Meta:
 403         unique_together = ('node', 'revision')
 404         app_label = 'forum'
 405
 406
 407 class NodeState(models.Model):
 408     node       = models.ForeignKey(Node, related_name='states')
 409     state_type = models.CharField(max_length=16)
 410     action     = models.OneToOneField('Action', related_name="node_state")
 411
 412     class Meta:
 413         unique_together = ('node', 'state_type')
 414         app_label = 'forum'
 415
 416