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
 175 class Node(BaseModel, NodeContent):
 176     __metaclass__ = NodeMetaClass
 177
 178     node_type            = models.CharField(max_length=16, default='node')
 179     parent               = models.ForeignKey('Node', related_name='children', null=True)
 180     abs_parent           = models.ForeignKey('Node', related_name='all_children', null=True)
 181
 182     added_at             = models.DateTimeField(default=datetime.datetime.now)
 183     score                 = models.IntegerField(default=0)
 184
 185     state_string          = models.TextField(default='')
 186     last_edited           = models.ForeignKey('Action', null=True, unique=True, related_name="edited_node")
 187
 188     last_activity_by       = models.ForeignKey(User, null=True)
 189     last_activity_at       = models.DateTimeField(null=True, blank=True)
 190
 191     tags                 = models.ManyToManyField('Tag', related_name='%(class)ss')
 192     active_revision       = models.OneToOneField('NodeRevision', related_name='active', null=True)
 193
 194     extra = PickledObjectField()
 195     extra_ref = models.ForeignKey('Node', null=True)
 196     extra_count = models.IntegerField(default=0)
 197
 198     marked = models.BooleanField(default=False)
 199
 200     comment_count = DenormalizedField("children", node_type="comment", canceled=False)
 201     flag_count = DenormalizedField("flags")
 202
 203     friendly_name = _("post")
 204
 205     objects = NodeManager()
 206
 207     def __unicode__(self):
 208         return self.headline
 209
 210     @classmethod
 211     def _generate_cache_key(cls, key, group="node"):
 212         return super(Node, cls)._generate_cache_key(key, group)
 213
 214     @classmethod
 215     def get_type(cls):
 216         return cls.__name__.lower()
 217
 218     @property
 219     def leaf(self):
 220         leaf_cls = NodeMetaClass.types.get(self.node_type, None)
 221
 222         if leaf_cls is None:
 223             return self
 224
 225         leaf = leaf_cls()
 226         leaf.__dict__ = self.__dict__
 227         return leaf
 228
 229     @property
 230     def nstate(self):
 231         state = self.__dict__.get('_nstate', None)
 232
 233         if state is None:
 234             state = NodeStateDict(self)
 235             self._nstate = state
 236
 237         return state
 238
 239     @property
 240     def nis(self):
 241         nis = self.__dict__.get('_nis', None)
 242
 243         if nis is None:
 244             nis = NodeStateQuery(self)
 245             self._nis = nis
 246
 247         return nis
 248
 249     @property
 250     def deleted(self):
 251         return self.nis.deleted
 252
 253     @property
 254     def absolute_parent(self):
 255         if not self.abs_parent_id:
 256             return self
 257
 258         return self.abs_parent
 259
 260     @property
 261     def summary(self):
 262         return strip_tags(self.html)[:300]
 263
 264     @models.permalink
 265     def get_revisions_url(self):
 266         return ('revisions', (), {'id': self.id})
 267
 268     def update_last_activity(self, user, save=False):
 269         self.last_activity_by = user
 270         self.last_activity_at = datetime.datetime.now()
 271
 272         if self.parent:
 273             self.parent.update_last_activity(user, save=True)
 274
 275         if save:
 276             self.save()
 277
 278     def _create_revision(self, user, number, **kwargs):
 279         revision = NodeRevision(author=user, revision=number, node=self, **kwargs)
 280         revision.save()
 281         return revision
 282
 283     def create_revision(self, user, **kwargs):
 284         number = self.revisions.aggregate(last=models.Max('revision'))['last'] + 1
 285         revision = self._create_revision(user, number, **kwargs)
 286         self.activate_revision(user, revision)
 287         return revision
 288
 289     def activate_revision(self, user, revision):
 290         self.title = revision.title
 291         self.tagnames = revision.tagnames
 292         self.body = revision.body
 293
 294         self.active_revision = revision
 295         self.update_last_activity(user)
 296
 297         self.save()
 298
 299     def _list_changes_in_tags(self):
 300         dirty = self.get_dirty_fields()
 301
 302         if not 'tagnames' in dirty:
 303             return None
 304         else:
 305             if self._original_state['tagnames']:
 306                 old_tags = set(name for name in self._original_state['tagnames'].split(u' '))
 307             else:
 308                 old_tags = set()
 309             new_tags = set(name for name in self.tagnames.split(u' ') if name)
 310
 311             return dict(
 312                 current=list(new_tags),
 313                 added=list(new_tags - old_tags),
 314                 removed=list(old_tags - new_tags)
 315             )
 316
 317     def _last_active_user(self):
 318         return self.last_edited and self.last_edited.by or self.author
 319
 320     def _process_changes_in_tags(self):
 321         tag_changes = self._list_changes_in_tags()
 322
 323         if tag_changes is not None:
 324             for name in tag_changes['added']:
 325                 try:
 326                     tag = Tag.objects.get(name=name)
 327                 except:
 328                     tag = Tag.objects.create(name=name, created_by=self._last_active_user())
 329
 330                 if not self.nis.deleted:
 331                     tag.used_count = models.F('used_count') + 1
 332                     tag.save()
 333
 334             if not self.nis.deleted:
 335                 for name in tag_changes['removed']:
 336                     try:
 337                         tag = Tag.objects.get(name=name)
 338                         tag.used_count = models.F('used_count') - 1
 339                         tag.save()
 340                     except:
 341                         pass
 342
 343             return True
 344
 345         return False
 346
 347     def mark_deleted(self, action):
 348         self.nstate.deleted = action
 349         self.save()
 350
 351         if action:
 352             for tag in self.tags.all():
 353                 tag.used_count = models.F('used_count') - 1
 354                 tag.save()
 355         else:
 356             for tag in Tag.objects.filter(name__in=self.tagname_list()):
 357                 tag.used_count = models.F('used_count') + 1
 358                 tag.save()
 359
 360     def save(self, *args, **kwargs):
 361         tags_changed = self._process_changes_in_tags()
 362
 363         if not self.id:
 364             self.node_type = self.get_type()
 365             super(BaseModel, self).save(*args, **kwargs)
 366             self.active_revision = self._create_revision(self.author, 1, title=self.title, tagnames=self.tagnames, 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