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         return super(NodeQuerySet, self).get(*args, **kwargs).leaf
  99
 100     def filter_state(self, **kwargs):
 101         apply_bool = lambda q, b: b and q or ~q
 102         return self.filter(*[apply_bool(models.Q(state_string__contains="(%s)" % s), b) for s, b in kwargs.items()])
 103
 104
 105 class NodeManager(CachedManager):
 106     use_for_related_fields = True
 107
 108     def get_query_set(self):
 109         qs = NodeQuerySet(self.model)
 110
 111         if self.model is not Node:
 112             return qs.filter(node_type=self.model.get_type())
 113         else:
 114             return qs
 115
 116     def get_for_types(self, types, *args, **kwargs):
 117         kwargs['node_type__in'] = [t.get_type() for t in types]
 118         return self.get(*args, **kwargs)
 119
 120     def filter_state(self, **kwargs):
 121         return self.all().filter_state(**kwargs)
 122
 123
 124 class NodeStateDict(object):
 125     def __init__(self, node):
 126         self.__dict__['_node'] = node
 127
 128     def __getattr__(self, name):
 129         if self.__dict__.get(name, None):
 130             return self.__dict__[name]
 131
 132         try:
 133             node = self.__dict__['_node']
 134             action = NodeState.objects.get(node=node, state_type=name).action
 135             self.__dict__[name] = action
 136             return action
 137         except:
 138             return None
 139
 140     def __setattr__(self, name, value):
 141         current = self.__getattr__(name)
 142
 143         if value:
 144             if current:
 145                 current.action = value
 146                 current.save()
 147             else:
 148                 node = self.__dict__['_node']
 149                 state = NodeState(node=node, action=value, state_type=name)
 150                 state.save()
 151                 self.__dict__[name] = value
 152
 153                 if not "(%s)" % name in node.state_string:
 154                     node.state_string = "%s(%s)" % (node.state_string, name)
 155                     node.save()
 156         else:
 157             if current:
 158                 node = self.__dict__['_node']
 159                 node.state_string = "".join("(%s)" % s for s in re.findall('\w+', node.state_string) if s != name)
 160                 node.save()
 161                 current.node_state.delete()
 162                 del self.__dict__[name]
 163
 164
 165 class NodeStateQuery(object):
 166     def __init__(self, node):
 167         self.__dict__['_node'] = node
 168
 169     def __getattr__(self, name):
 170         node = self.__dict__['_node']
 171         return "(%s)" % name in node.state_string
 172
 173
 174 class Node(BaseModel, NodeContent):
 175     __metaclass__ = NodeMetaClass
 176
 177     node_type            = models.CharField(max_length=16, default='node')
 178     parent               = models.ForeignKey('Node', related_name='children', null=True)
 179     abs_parent           = models.ForeignKey('Node', related_name='all_children', null=True)
 180
 181     added_at             = models.DateTimeField(default=datetime.datetime.now)
 182     score                 = models.IntegerField(default=0)
 183
 184     state_string          = models.TextField(default='')
 185     last_edited           = models.ForeignKey('Action', null=True, unique=True, related_name="edited_node")
 186
 187     last_activity_by       = models.ForeignKey(User, null=True)
 188     last_activity_at       = models.DateTimeField(null=True, blank=True)
 189
 190     tags                 = models.ManyToManyField('Tag', related_name='%(class)ss')
 191     active_revision       = models.OneToOneField('NodeRevision', related_name='active', null=True)
 192
 193     extra = PickledObjectField()
 194     extra_ref = models.ForeignKey('Node', null=True)
 195     extra_count = models.IntegerField(default=0)
 196
 197     marked = models.BooleanField(default=False)
 198
 199     comment_count = DenormalizedField("children", node_type="comment", canceled=False)
 200     flag_count = DenormalizedField("flags")
 201
 202     friendly_name = _("post")
 203
 204     objects = NodeManager()
 205
 206     def __unicode__(self):
 207         return self.headline
 208
 209     @classmethod
 210     def _generate_cache_key(cls, key, group="node"):
 211         return super(Node, cls)._generate_cache_key(key, group)
 212
 213     @classmethod
 214     def get_type(cls):
 215         return cls.__name__.lower()
 216
 217     @property
 218     def leaf(self):
 219         leaf_cls = NodeMetaClass.types.get(self.node_type, None)
 220
 221         if leaf_cls is None:
 222             return self
 223
 224         leaf = leaf_cls()
 225         leaf.__dict__ = self.__dict__
 226         return leaf
 227
 228     @property
 229     def nstate(self):
 230         state = self.__dict__.get('_nstate', None)
 231
 232         if state is None:
 233             state = NodeStateDict(self)
 234             self._nstate = state
 235
 236         return state
 237
 238     @property
 239     def nis(self):
 240         nis = self.__dict__.get('_nis', None)
 241
 242         if nis is None:
 243             nis = NodeStateQuery(self)
 244             self._nis = nis
 245
 246         return nis
 247
 248     @property
 249     def deleted(self):
 250         return self.nis.deleted
 251
 252     @property
 253     def absolute_parent(self):
 254         if not self.abs_parent_id:
 255             return self
 256
 257         return self.abs_parent
 258
 259     @property
 260     def summary(self):
 261         return strip_tags(self.html)[:300]
 262
 263     @models.permalink
 264     def get_revisions_url(self):
 265         return ('revisions', (), {'id': self.id})
 266
 267     def update_last_activity(self, user, save=False):
 268         self.last_activity_by = user
 269         self.last_activity_at = datetime.datetime.now()
 270
 271         if self.parent:
 272             self.parent.update_last_activity(user, save=True)
 273
 274         if save:
 275             self.save()
 276
 277     def _create_revision(self, user, number, **kwargs):
 278         revision = NodeRevision(author=user, revision=number, node=self, **kwargs)
 279         revision.save()
 280         return revision
 281
 282     def create_revision(self, user, **kwargs):
 283         number = self.revisions.aggregate(last=models.Max('revision'))['last'] + 1
 284         revision = self._create_revision(user, number, **kwargs)
 285         self.activate_revision(user, revision)
 286         return revision
 287
 288     def activate_revision(self, user, revision):
 289         self.title = revision.title
 290         self.tagnames = revision.tagnames
 291         self.body = revision.body
 292
 293         self.active_revision = revision
 294         self.update_last_activity(user)
 295
 296         self.save()
 297
 298     def _list_changes_in_tags(self):
 299         dirty = self.get_dirty_fields()
 300
 301         if not 'tagnames' in dirty:
 302             return None
 303         else:
 304             if self._original_state['tagnames']:
 305                 old_tags = set(name for name in self._original_state['tagnames'].split(u' '))
 306             else:
 307                 old_tags = set()
 308             new_tags = set(name for name in self.tagnames.split(u' ') if name)
 309
 310             return dict(
 311                     current=list(new_tags),
 312                     added=list(new_tags - old_tags),
 313                     removed=list(old_tags - new_tags)
 314                     )
 315
 316     def _last_active_user(self):
 317         return self.last_edited and self.last_edited.by or self.author
 318
 319     def _process_changes_in_tags(self):
 320         tag_changes = self._list_changes_in_tags()
 321
 322         if tag_changes is not None:
 323             for name in tag_changes['added']:
 324                 try:
 325                     tag = Tag.objects.get(name=name)
 326                 except:
 327                     tag = Tag.objects.create(name=name, created_by=self._last_active_user())
 328
 329                 if not self.nis.deleted:
 330                     tag.add_to_usage_count(1)
 331                     tag.save()
 332
 333             if not self.nis.deleted:
 334                 for name in tag_changes['removed']:
 335                     try:
 336                         tag = Tag.objects.get(name=name)
 337                         tag.add_to_usage_count(-1)
 338                         tag.save()
 339                     except:
 340                         pass
 341
 342             return True
 343
 344         return False
 345
 346     def mark_deleted(self, action):
 347         self.nstate.deleted = action
 348         self.save()
 349
 350         if action:
 351             for tag in self.tags.all():
 352                 tag.add_to_usage_count(-1)
 353                 tag.save()
 354         else:
 355             for tag in Tag.objects.filter(name__in=self.tagname_list()):
 356                 tag.add_to_usage_count(1)
 357                 tag.save()
 358
 359     def save(self, *args, **kwargs):
 360         tags_changed = self._process_changes_in_tags()
 361
 362         if not self.id:
 363             self.node_type = self.get_type()
 364             super(BaseModel, self).save(*args, **kwargs)
 365             self.active_revision = self._create_revision(self.author, 1, title=self.title, tagnames=self.tagnames,
 366                                                          body=self.body)
 367             self.update_last_activity(self.author)
 368
 369         if self.parent_id and not self.abs_parent_id:
 370             self.abs_parent = self.parent.absolute_parent
 371
 372         super(Node, self).save(*args, **kwargs)
 373         if tags_changed: self.tags = list(Tag.objects.filter(name__in=self.tagname_list()))
 374
 375     class Meta:
 376         app_label = 'forum'
 377
 378
 379 class NodeRevision(BaseModel, NodeContent):
 380     node       = models.ForeignKey(Node, related_name='revisions')
 381     summary    = models.CharField(max_length=300)
 382     revision   = models.PositiveIntegerField()
 383     revised_at = models.DateTimeField(default=datetime.datetime.now)
 384
 385     class Meta:
 386         unique_together = ('node', 'revision')
 387         app_label = 'forum'
 388
 389
 390 class NodeState(models.Model):
 391     node       = models.ForeignKey(Node, related_name='states')
 392     state_type = models.CharField(max_length=16)
 393     action     = models.OneToOneField('Action', related_name="node_state")
 394
 395     class Meta:
 396         unique_together = ('node', 'state_type')
 397         app_label = 'forum'
 398
 399