plone.app.discussion/plone/app/discussion/conversation.py

330 lines
9.8 KiB
Python

"""The conversation and replies adapters
The conversation is responsible for storing all comments. It provides a
dict-like API for accessing comments, where keys are integers and values
are IComment objects. It also provides features for finding comments quickly.
The two IReplies adapters - one for the IConversation and one for IComment -
manipulate the same data structures, but provide an API for finding and
manipulating the comments directly in reply to a particular comment or at the
top level of the conversation.
"""
import time
from persistent import Persistent
from zope.interface import implements, implementer
from zope.component import adapts, adapter
from zope.annotation.interfaces import IAnnotations, IAnnotatable
from zope.event import notify
from Acquisition import aq_base
from Acquisition import Explicit
from OFS.Traversable import Traversable
from OFS.event import ObjectWillBeAddedEvent
from OFS.event import ObjectWillBeRemovedEvent
from zope.app.container.contained import ContainerModifiedEvent
from zope.app.container.contained import ObjectAddedEvent
from zope.app.container.contained import ObjectRemovedEvent
from BTrees.OIBTree import OIBTree
try:
# These exist in new versions, but not in the one that comes with Zope 2.10.
from BTrees.LOBTree import LOBTree
from BTrees.LLBTree import LLSet
except ImportError:
from BTrees.OOBTree import OOBTree as LOBTree
from BTrees.OOBTree import OOSet as LLSet
from plone.app.discussion.interfaces import IConversation, IReplies
from plone.app.discussion.comment import Comment
ANNOTATION_KEY = 'plone.app.discussion:conversation'
class Conversation(Traversable, Persistent, Explicit):
"""A conversation is a container for all comments on a content object.
It manages internal data structures for comment threading and efficient
comment lookup.
"""
implements(IConversation)
def __init__(self, id="++comment++"):
self.id = id
# username -> count of comments; key is removed when count reaches 0
self._commentators = OIBTree()
# id -> comment - find comment by id
self._comments = LOBTree()
# id -> IISet (children) - find all children for a given comment. 0 signifies root.
self._children = LOBTree()
def getId(self):
"""Get the id of
"""
return self.id
@property
def enabled(self):
# TODO - check __parent__'s settings + global settings
return True
@property
def total_comments(self):
return len(self._comments)
@property
def last_comment_date(self):
try:
return self._comments[self._comments.maxKey()].creation_date
except (ValueError, KeyError, AttributeError,):
return None
@property
def commentators(self):
return self._commentators.keys()
def getComments(self, start=0, size=None):
"""Get unthreaded comments
"""
# TODO - batching
return self._comments.values()
def getThreads(self, start=0, size=None, root=None, depth=None):
"""Get threaded comments
"""
# TODO - build threads
return self._comments.values()
def addComment(self, comment):
"""Add a new comment. The parent id should have been set already. The
comment id may be modified to find a free key. The id used will be
returned.
"""
# Make sure we don't have a wrapped object
comment = aq_base(comment)
id = long(time.time() * 1e6)
while id in self._comments:
id += 1
comment.comment_id = id
notify(ObjectWillBeAddedEvent(comment, self, id))
self._comments[id] = comment
comment.__parent__ = self
# Record unique users who've commented (for logged in users only)
commentator = comment.author_username
if commentator:
if not commentator in self._commentators:
self._commentators[commentator] = 0
self._commentators[commentator] += 1
reply_to = comment.in_reply_to
if not reply_to:
# top level comments are in reply to the faux id 0
comment.in_reply_to = reply_to = 0
if not reply_to in self._children:
self._children[reply_to] = LLSet()
self._children[reply_to].insert(id)
# Notify that the object is added. The object must here be
# acquisition wrapped or the indexing will fail.
notify(ObjectAddedEvent(comment.__of__(self), self, id))
notify(ContainerModifiedEvent(self))
return id
# Dict API
def __len__(self):
return len(self._comments)
def __contains__(self, key):
return long(key) in self._comments
def __getitem__(self, key):
"""Get an item by its long key
"""
return self._comments[long(key)].__of__(self)
def __delitem__(self, key):
"""Delete an item by its long key
"""
key = long(key)
comment = self[key].__of__(self)
commentator = comment.author_username
notify(ObjectWillBeRemovedEvent(comment, self, key))
self._comments.remove(key)
notify(ObjectRemovedEvent(comment, self, key))
if commentator and commentator in self._commentators:
if self._commentators[commentator] <= 1:
del self._commentators[commentator]
else:
self._commentators[commentator] -= 1
notify(ContainerModifiedEvent(self))
def __iter__(self):
return iter(self._comments)
def get(self, key, default=None):
comment = self._comments.get(long(key), default)
if comment is default:
return default
return comment.__of__(self)
def keys(self):
return self._comments.keys()
def items(self):
return [(i[0], i[1].__of__(self),) for i in self._comments.items()]
def values(self):
return [v.__of__(self) for v in self._comments.values()]
def iterkeys(self):
return self._comments.iterkeys()
def itervalues(self):
for v in self._comments.itervalues():
yield v.__of__(self)
def iteritems(self):
for k, v in self._comments.iteritems():
yield (k, v.__of__(self),)
@implementer(IConversation)
@adapter(IAnnotatable)
def conversationAdapterFactory(content):
"""Adapter factory to fetch a conversation from annotations
"""
annotions = IAnnotations(content)
if not ANNOTATION_KEY in annotions:
conversation = Conversation()
annotions[ANNOTATION_KEY] = conversation
conversation = annotions[ANNOTATION_KEY]
return conversation
class ConversationReplies(object):
"""An IReplies adapter for conversations.
This makes it easy to work with top-level comments.
"""
implements(IReplies)
adapts(Conversation) # relies on implementation details
def __init__(self, context):
self.conversation = context
self.children = self.conversation._children.get(0, LLSet())
def addComment(self, comment):
comment.in_reply_to = None
return self.conversation.addComment(comment)
# Dict API
def __len__(self):
return len(self.children)
def __contains__(self, key):
return long(key) in self.children
# TODO: Should __getitem__, get, __iter__, values(), items() and iter* return aq-wrapped comments?
def __getitem__(self, key):
"""Get an item by its long key
"""
key = long(key)
if key not in self.children:
raise KeyError(key)
return self.conversation[key]
def __delitem__(self, key):
"""Delete an item by its long key
"""
key = long(key)
if key not in self.children:
raise KeyError(key)
del self.conversation[key]
def __iter__(self):
return iter(self.children)
def get(self, key, default=None):
key = long(key)
if key not in self.children:
return default
return self.conversation.get(key)
def keys(self):
return self.children
def items(self):
return [(k, self.conversation[k]) for k in self.children]
def values(self):
return [self.conversation[k] for k in self.children]
def iterkeys(self):
return iter(self.children)
def itervalues(self):
for key in self.children:
yield self.conversation[key]
def iteritems(self):
for key in self.children:
yield (key, self.conversation[key],)
class CommentReplies(ConversationReplies):
"""An IReplies adapter for comments.
This makes it easy to work with replies to specific comments.
"""
implements(IReplies)
# depends on implementation details of conversation
# most likely, anyone writing a different type of Conversation will also
# have a different type of Comment
adapts(Comment)
def __init__(self, context):
self.comment = context
self.conversation = self.comment.__parent__
if self.conversation is None or not hasattr(self.conversation, '_children'):
raise TypeError("This adapter doesn't know what to do with the parent conversation")
self.comment_id = self.comment.comment_id
self.children = self.conversation._children.get(self.comment_id, LLSet())
def addComment(self, comment):
comment.in_reply_to = self.comment_id
return self.conversation.addComment(comment)
# Dict API is inherited, written in terms of self.conversation and self.children