plone.app.discussion/plone/app/discussion/comment.py

# -*- coding: utf-8 -*-
"""The default comment class and factory.
"""

import logging

from datetime import datetime

from smtplib import SMTPException

from zope.annotation.interfaces import IAnnotatable

from zope.component.factory import Factory
from zope.component import queryUtility

from zope.i18n import translate
from zope.i18nmessageid import Message
from zope.interface import implements

from Acquisition import aq_parent, aq_base, Implicit

from OFS.owner import Owned

from persistent import Persistent

from Products.CMFCore.DynamicType import DynamicType
from Products.CMFCore.utils import getToolByName

from Products.CMFPlone.utils import safe_unicode

from OFS.Traversable import Traversable

from plone.registry.interfaces import IRegistry

from plone.app.discussion import PloneAppDiscussionMessageFactory as _
from plone.app.discussion.interfaces import IComment
from plone.app.discussion.interfaces import IConversation
from plone.app.discussion.interfaces import IDiscussionSettings

from Products.CMFCore.CMFCatalogAware import CatalogAware
from Products.CMFCore.CMFCatalogAware import WorkflowAware

from OFS.role import RoleManager


COMMENT_TITLE = _(
    u"comment_title",
    default=u"${creator} on ${content}")

MAIL_NOTIFICATION_MESSAGE = _(
    u"mail_notification_message",
    default=u"A comment on '${title}' "
             "has been posted here: ${link}\n\n"
             "---\n"
             "${text}\n"
             "---\n")

MAIL_NOTIFICATION_MESSAGE_MODERATOR = _(
    u"mail_notification_message_moderator",
    default=u"A comment on '${title}' "
             "has been posted here: ${link}\n\n"
             "---\n"
             "${text}\n"
             "---\n\n"
             "Approve comment:\n${link_approve}\n\n"
             "Delete comment:\n${link_delete}\n")

logger = logging.getLogger("plone.app.discussion")


class Comment(CatalogAware, WorkflowAware, DynamicType, Traversable,
              RoleManager, Owned, Implicit, Persistent):
    """A comment.
    
    This object attempts to be as lightweight as possible. We implement a
    number of standard methods instead of subclassing, to have total control
    over what goes into the object.
    """
    
    implements(IComment)
    
    meta_type = portal_type = 'Discussion Item'
    # This needs to be kept in sync with types/Discussion_Item.xml title
    fti_title = 'Comment'
    
    __parent__ = None
    
    comment_id = None # long
    in_reply_to = None # long
    
    title = u""
    
    mime_type = None
    text = u""
    
    creator = None
    creation_date = None
    modification_date = None
    
    author_username = None
    
    author_name = None
    author_email = None
    
    user_notification = None
    
    # Note: we want to use zope.component.createObject() to instantiate
    # comments as far as possible. comment_id and __parent__ are set via
    # IConversation.addComment().
    
    def __init__(self):
        self.creation_date = self.modification_date = datetime.utcnow()
    
    @property
    def __name__(self):
        return self.comment_id and unicode(self.comment_id) or None
    
    @property
    def id(self):
        return self.comment_id and str(self.comment_id) or None
    
    def getId(self):
        """The id of the comment, as a string.
        """
        return self.id
    
    def getText(self, targetMimetype=None):
        """The body text of a comment.
        """
        transforms = getToolByName(self, 'portal_transforms')
        
        if targetMimetype is None:
            targetMimetype = 'text/x-html-safe'
        
        sourceMimetype = getattr(self, 'mime_type', None)
        if sourceMimetype is None:
            registry = queryUtility(IRegistry)
            settings = registry.forInterface(IDiscussionSettings, check=False)
            sourceMimetype = settings.text_transform
        text = self.text
        if isinstance(text, unicode):
            text = text.encode('utf8')
        return transforms.convertTo(targetMimetype,
                                    text,
                                    context=self,
                                    mimetype=sourceMimetype).getData()
    
    def Title(self):
        """The title of the comment.
        """
        
        if self.title:
            return self.title
        
        if not self.creator:
            creator = translate(Message(_(u"label_anonymous",
                                          default=u"Anonymous")))
        else:
            creator = self.creator
            creator = creator
        
        # Fetch the content object (the parent of the comment is the
        # conversation, the parent of the conversation is the content object).
        content = aq_base(self.__parent__.__parent__)
        title = translate(
            Message(COMMENT_TITLE,
                    mapping={'creator': creator,
                             'content': safe_unicode(content.Title())}))
        return title
    
    def Creator(self):
        """The name of the person who wrote the comment.
        """
        return self.creator
    
    def Type(self):
        """The Discussion Item content type.
        """
        return self.fti_title
    
    # CMF's event handlers assume any IDynamicType has these :(
    
    def opaqueItems(self): # pragma: no cover
        return []
    
    def opaqueIds(self): # pragma: no cover
        return []
    
    def opaqueValues(self): # pragma: no cover
        return []

CommentFactory = Factory(Comment)


def notify_workflow(obj, event):
    """Tell the workflow tool when a comment is added
    """
    tool = getToolByName(obj, 'portal_workflow', None)
    if tool is not None:
        tool.notifyCreated(obj)


def notify_content_object(obj, event):
    """Tell the content object when a comment is added
    """
    content_obj = aq_parent(aq_parent(obj))
    content_obj.reindexObject(idxs=('total_comments',
                                    'last_comment_date',
                                    'commentators',))


def notify_content_object_deleted(obj, event):
    """Remove all comments of a content object when the content object has been
       deleted.
    """
    if IAnnotatable.providedBy(obj):
        conversation = IConversation(obj)
        while conversation:
            del conversation[conversation.keys()[0]]


def notify_content_object_moved(obj, event):
    """Update all comments of a content object that has been moved.
    """
    if event.oldParent is None or event.newParent is None \
       or event.oldName is None or event.newName is None \
       or event.oldParent == event.newParent:
        return
    # Remove comments at the old location from catalog
    catalog = getToolByName(obj, 'portal_catalog')
    for brain in catalog.searchResults(portal_type = 'Discussion Item'):
        catalog.uncatalog_object(brain.getPath())
    # Reindex comment at the new location
    conversation = IConversation(obj)
    for comment in conversation.getComments():
        comment.__parent__.__parent__.__parent__ = event.newParent
        catalog.reindexObject(aq_base(comment))
    

def notify_user(obj, event):
    """Tell users when a comment has been added.
       
       This method composes and sends emails to all users that have added a
       comment to this conversation and enabled user notification.
       
       This requires the user_notification setting to be enabled in the
       discussion control panel.
    """
    
    # Check if user notification is enabled
    registry = queryUtility(IRegistry)
    settings = registry.forInterface(IDiscussionSettings, check=False)
    if not settings.user_notification_enabled:
        return
    
    # Get informations that are necessary to send an email
    mail_host = getToolByName(obj, 'MailHost')
    portal_url = getToolByName(obj, 'portal_url')
    portal = portal_url.getPortalObject()
    sender = portal.getProperty('email_from_address')

    # Check if a sender address is available
    if not sender:
        return

    # Compose and send emails to all users that have add a comment to this
    # conversation and enabled user_notification.
    conversation = aq_parent(obj)
    content_object = aq_parent(conversation)

    # Avoid sending multiple notification emails to the same person
    # when he has commented multiple times.
    emails = set()
    for comment in conversation.getComments():
        if (obj != comment and
            comment.user_notification and comment.author_email):
            emails.add(comment.author_email)
    
    if not emails:
        return
    
    subject = translate(_(u"A comment has been posted."),
                        context=obj.REQUEST)
    message = translate(Message(
            MAIL_NOTIFICATION_MESSAGE,
            mapping={'title': safe_unicode(content_object.title),
                     'link': content_object.absolute_url() + 
                             '/view#' + obj.id,
                     'text': obj.text}),
            context=obj.REQUEST)
    for email in emails:
        # Send email
        try:
            mail_host.send(message,
                           email,
                           sender,
                           subject,
                           charset='utf-8')
        except SMTPException:
            logger.error('SMTP exception while trying to send an ' +
                         'email from %s to %s',
                         sender,
                         email)


def notify_moderator(obj, event):
    """Tell the moderator when a comment needs attention.
       
       This method sends an email to the moderator if comment moderation a new 
       comment has been added that needs to be approved.
       
       The moderator_notification setting has to be enabled in the discussion
       control panel.
       
       Configure the moderator e-mail address in the discussion control panel.
       If no moderator is configured but moderator notifications are turned on,
       the site admin email (from the mail control panel) will be used.
    """
    # Check if moderator notification is enabled
    registry = queryUtility(IRegistry)
    settings = registry.forInterface(IDiscussionSettings, check=False)
    if not settings.moderator_notification_enabled:
        return
    
    # Get informations that are necessary to send an email
    mail_host = getToolByName(obj, 'MailHost')
    portal_url = getToolByName(obj, 'portal_url')
    portal = portal_url.getPortalObject()
    sender = portal.getProperty('email_from_address')
    
    if settings.moderator_email:
        mto = settings.moderator_email
    else:
        mto = sender
    
    # Check if a sender address is available
    if not sender:
        return
    
    conversation = aq_parent(obj)
    content_object = aq_parent(conversation)
    
    # Compose email
    subject = translate(_(u"A comment has been posted."), context=obj.REQUEST)
    message = translate(Message(MAIL_NOTIFICATION_MESSAGE_MODERATOR,
        mapping={
            'title': safe_unicode(content_object.title),
            'link': content_object.absolute_url() + '/view#' + obj.id,
            'text': obj.text,
            'link_approve': obj.absolute_url() + '/@@moderate-publish-comment',
            'link_delete': obj.absolute_url() + '/@@moderate-delete-comment',
            }),
        context=obj.REQUEST)
    
    # Send email
    try:
        mail_host.send(message, mto, sender, subject, charset='utf-8')
    except SMTPException, e:
        logger.error('SMTP exception (%s) while trying to send an ' +
                     'email notification to the comment moderator ' +
                     '(from %s to %s, message: %s)',
                     e,
                     sender,
                     mto,
                     message)