+
−"""some hooks and views to handle notification on entity's changes
+
−
+
−:organization: Logilab
+
−:copyright: 2001-2009 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.
+
−:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
+
−:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses
+
−"""
+
−__docformat__ = "restructuredtext en"
+
−_ = unicode
+
−
+
−from base64 import b64encode, b64decode
+
−from itertools import repeat
+
−from time import time
+
−try:
+
−    from socket import gethostname
+
−except ImportError:
+
−    def gethostname(): # gae
+
−        return 'XXX'
+
−
+
−from logilab.common.textutils import normalize_text
+
−from logilab.common.deprecation import class_renamed
+
−
+
−from cubicweb import RegistryException
+
−from cubicweb.selectors import implements, yes
+
−from cubicweb.view import EntityView, Component
+
−from cubicweb.common.mail import format_mail
+
−
+
−from cubicweb.server.pool import PreCommitOperation
+
−from cubicweb.server.hookhelper import SendMailOp
+
−from cubicweb.server.hooksmanager import Hook
+
−
+
−
+
−class RecipientsFinder(Component):
+
−    """this component is responsible to find recipients of a notification
+
−
+
−    by default user's with their email set are notified if any, else the default
+
−    email addresses specified in the configuration are used
+
−    """
+
−    id = 'recipients_finder'
+
−    __select__ = yes()
+
−    user_rql = ('Any X,E,A WHERE X is CWUser, X in_state S, S name "activated",'
+
−                'X primary_email E, E address A')
+
−
+
−    def recipients(self):
+
−        mode = self.config['default-recipients-mode']
+
−        if mode == 'users':
+
−            # use unsafe execute else we may don't have the right to see users
+
−            # to notify...
+
−            execute = self.req.unsafe_execute
+
−            dests = [(u.get_email(), u.property_value('ui.language'))
+
−                     for u in execute(self.user_rql, build_descr=True, propagate=True).entities()]
+
−        elif mode == 'default-dest-addrs':
+
−            lang = self.vreg.property_value('ui.language')
+
−            dests = zip(self.config['default-dest-addrs'], repeat(lang))
+
−        else: # mode == 'none'
+
−            dests = []
+
−        return dests
+
−
+
−
+
−# hooks #######################################################################
+
−
+
−class RenderAndSendNotificationView(PreCommitOperation):
+
−    """delay rendering of notification view until precommit"""
+
−    def precommit_event(self):
+
−        if self.view.rset[0][0] in self.session.query_data('pendingeids', ()):
+
−            return # entity added and deleted in the same transaction
+
−        self.view.render_and_send(**getattr(self, 'viewargs', {}))
+
−
+
−class StatusChangeHook(Hook):
+
−    """notify when a workflowable entity has its state modified"""
+
−    events = ('after_add_entity',)
+
−    accepts = ('TrInfo',)
+
−
+
−    def call(self, session, entity):
+
−        if not entity.from_state: # not a transition
+
−            return
+
−        rset = entity.related('wf_info_for')
+
−        try:
+
−            view = session.vreg.select('views', 'notif_status_change',
+
−                                            session, rset, row=0)
+
−        except RegistryException:
+
−            return
+
−        comment = entity.printable_value('comment', format='text/plain')
+
−        if comment:
+
−            comment = normalize_text(comment, 80,
+
−                                     rest=entity.comment_format=='text/rest')
+
−        RenderAndSendNotificationView(session, view=view, viewargs={
+
−            'comment': comment, 'previous_state': entity.previous_state.name,
+
−            'current_state': entity.new_state.name})
+
−
+
−
+
−class RelationChangeHook(Hook):
+
−    events = ('before_add_relation', 'after_add_relation',
+
−              'before_delete_relation', 'after_delete_relation')
+
−    accepts = ('Any',)
+
−    def call(self, session, fromeid, rtype, toeid):
+
−        """if a notification view is defined for the event, send notification
+
−        email defined by the view
+
−        """
+
−        rset = session.eid_rset(fromeid)
+
−        vid = 'notif_%s_%s' % (self.event,  rtype)
+
−        try:
+
−            view = session.vreg.select('views', vid, session, rset, row=0)
+
−        except RegistryException:
+
−            return
+
−        RenderAndSendNotificationView(session, view=view)
+
−
+
−
+
−class EntityChangeHook(Hook):
+
−    events = ('after_add_entity',
+
−              'after_update_entity')
+
−    accepts = ('Any',)
+
−    def call(self, session, entity):
+
−        """if a notification view is defined for the event, send notification
+
−        email defined by the view
+
−        """
+
−        rset = entity.as_rset()
+
−        vid = 'notif_%s' % self.event
+
−        try:
+
−            view = session.vreg.select('views', vid, session, rset, row=0)
+
−        except RegistryException:
+
−            return
+
−        RenderAndSendNotificationView(session, view=view)
+
−
+
−
+
−# abstract or deactivated notification views and mixin ########################
+
−
+
−class NotificationView(EntityView):
+
−    """abstract view implementing the email API
+
−
+
−    all you have to do by default is :
+
−    * set id and accepts attributes to match desired events and entity types
+
−    * set a content attribute to define the content of the email (unless you
+
−      override call)
+
−    """
+
−    msgid_timestamp = True
+
−
+
−    def recipients(self):
+
−        finder = self.vreg.select('components', 'recipients_finder', self.req,
+
−                                  rset=self.rset)
+
−        return finder.recipients()
+
−
+
−    def subject(self):
+
−        entity = self.entity(0, 0)
+
−        subject = self.req._(self.message)
+
−        etype = entity.dc_type()
+
−        eid = entity.eid
+
−        login = self.user_login()
+
−        return self.req._('%(subject)s %(etype)s #%(eid)s (%(login)s)') % locals()
+
−
+
−    def user_login(self):
+
−        # req is actually a session (we are on the server side), and we have to
+
−        # prevent nested internal session
+
−        return self.req.actual_session().user.login
+
−
+
−    def context(self, **kwargs):
+
−        entity = self.entity(0, 0)
+
−        for key, val in kwargs.iteritems():
+
−            if val and isinstance(val, unicode) and val.strip():
+
−               kwargs[key] = self.req._(val)
+
−        kwargs.update({'user': self.user_login(),
+
−                       'eid': entity.eid,
+
−                       'etype': entity.dc_type(),
+
−                       'url': entity.absolute_url(),
+
−                       'title': entity.dc_long_title(),})
+
−        return kwargs
+
−
+
−    def cell_call(self, row, col=0, **kwargs):
+
−        self.w(self.req._(self.content) % self.context(**kwargs))
+
−
+
−    def construct_message_id(self, eid):
+
−        return construct_message_id(self.config.appid, eid, self.msgid_timestamp)
+
−
+
−    def render_and_send(self, **kwargs):
+
−        """generate and send an email message for this view"""
+
−        self._kwargs = kwargs
+
−        recipients = self.recipients()
+
−        if not recipients:
+
−            self.info('skipping %s notification, no recipients', self.id)
+
−            return
+
−        if not isinstance(recipients[0], tuple):
+
−            from warnings import warn
+
−            warn('recipients should now return a list of 2-uple (email, language)',
+
−                 DeprecationWarning, stacklevel=1)
+
−            lang = self.vreg.property_value('ui.language')
+
−            recipients = zip(recipients, repeat(lang))
+
−        entity = self.entity(0, 0)
+
−        # if the view is using timestamp in message ids, no way to reference
+
−        # previous email
+
−        if not self.msgid_timestamp:
+
−            refs = [self.construct_message_id(eid)
+
−                    for eid in entity.notification_references(self)]
+
−        else:
+
−            refs = ()
+
−        msgid = self.construct_message_id(entity.eid)
+
−        userdata = self.req.user_data()
+
−        origlang = self.req.lang
+
−        for emailaddr, lang in recipients:
+
−            self.req.set_language(lang)
+
−            # since the same view (eg self) may be called multiple time and we
+
−            # need a fresh stream at each iteration, reset it explicitly
+
−            self.w = None
+
−            # XXX call render before subject to set .row/.col attributes on the
+
−            #     view
+
−            content = self.render(row=0, col=0, **kwargs)
+
−            subject = self.subject()
+
−            msg = format_mail(userdata, [emailaddr], content, subject,
+
−                              config=self.config, msgid=msgid, references=refs)
+
−            self.send([emailaddr], msg)
+
−        # restore language
+
−        self.req.set_language(origlang)
+
−
+
−    def send(self, recipients, msg):
+
−        SendMailOp(self.req, recipients=recipients, msg=msg)
+
−
+
−
+
−def construct_message_id(appid, eid, withtimestamp=True):
+
−    if withtimestamp:
+
−        addrpart = 'eid=%s&timestamp=%.10f' % (eid, time())
+
−    else:
+
−        addrpart = 'eid=%s' % eid
+
−    # we don't want any equal sign nor trailing newlines
+
−    leftpart = b64encode(addrpart, '.-').rstrip().rstrip('=')
+
−    return '<%s@%s.%s>' % (leftpart, appid, gethostname())
+
−
+
−
+
−def parse_message_id(msgid, appid):
+
−    if msgid[0] == '<':
+
−        msgid = msgid[1:]
+
−    if msgid[-1] == '>':
+
−        msgid = msgid[:-1]
+
−    try:
+
−        values, qualif = msgid.split('@')
+
−        padding = len(values) % 4
+
−        values = b64decode(str(values + '='*padding), '.-')
+
−        values = dict(v.split('=') for v in values.split('&'))
+
−        fromappid, host = qualif.split('.', 1)
+
−    except:
+
−        return None
+
−    if appid != fromappid or host != gethostname():
+
−        return None
+
−    return values
+
−
+
−
+
−class StatusChangeMixIn(object):
+
−    id = 'notif_status_change'
+
−    msgid_timestamp = True
+
−    message = _('status changed')
+
−    content = _("""
+
−%(user)s changed status from <%(previous_state)s> to <%(current_state)s> for entity
+
−'%(title)s'
+
−
+
−%(comment)s
+
−
+
−url: %(url)s
+
−""")
+
−
+
−
+
−###############################################################################
+
−# Actual notification views.                                                  #
+
−#                                                                             #
+
−# disable them at the recipients_finder level if you don't want them          #
+
−###############################################################################
+
−
+
−# XXX should be based on dc_title/dc_description, no?
+
−
+
−class ContentAddedView(NotificationView):
+
−    __abstract__ = True
+
−    id = 'notif_after_add_entity'
+
−    msgid_timestamp = False
+
−    message = _('new')
+
−    content = """
+
−%(title)s
+
−
+
−%(content)s
+
−
+
−url: %(url)s
+
−"""
+
−
+
−    def context(self, **kwargs):
+
−        entity = self.entity(0, 0)
+
−        content = entity.printable_value(self.content_attr, format='text/plain')
+
−        if content:
+
−            contentformat = getattr(entity, self.content_attr + '_format', 'text/rest')
+
−            content = normalize_text(content, 80, rest=contentformat=='text/rest')
+
−        return super(ContentAddedView, self).context(content=content, **kwargs)
+
−
+
−    def subject(self):
+
−        entity = self.entity(0, 0)
+
−        return  u'%s #%s (%s)' % (self.req.__('New %s' % entity.e_schema),
+
−                                  entity.eid, self.user_login())
+
−
+
−NormalizedTextView = class_renamed('NormalizedTextView', ContentAddedView)