diff -r 000000000000 -r b97547f5f1fa sobjects/notification.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sobjects/notification.py	Wed Nov 05 15:52:50 2008 +0100
@@ -0,0 +1,305 @@
+"""some hooks and views to handle notification on entity's changes
+
+:organization: Logilab
+:copyright: 2001-2008 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
+"""
+__docformat__ = "restructuredtext en"
+
+from base64 import b64encode, b64decode
+from itertools import repeat
+from time import time
+try:
+    from socket import gethostname
+except ImportError:
+    def gethostname():
+        return 'XXX'
+
+from logilab.common.textutils import normalize_text
+
+from cubicweb import RegistryException
+from cubicweb.common.view import EntityView
+from cubicweb.common.appobject import Component
+from cubicweb.common.registerers import accepts_registerer
+from cubicweb.common.selectors import accept_selector
+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
+
+_ = unicode
+
+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'
+    __registerer__ = accepts_registerer
+    __selectors__ = (accept_selector,)
+    accepts = ('Any',)
+    user_rql = ('Any X,E,A WHERE X is EUser, 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_view('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_view(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_view(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)
+    """
+    accepts = ()
+    id = None
+    msgid_timestamp = True
+    
+    def recipients(self):
+        finder = self.vreg.select_component('recipients_finder',
+                                            req=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 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%s notification which has no recipients',
+                      self.id, self.accepts)
+            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
+            # call dispatch before subject to set .row/.col attributes on the view :/
+            content = self.dispatch(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
+""")
+
+
+class ContentAddedMixIn(object):
+    """define emailcontent view for entity types for which you want to be notified
+    """
+    id = 'notif_after_add_entity' 
+    msgid_timestamp = False
+    message = _('new')
+    content = """
+%(title)s
+
+%(content)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 NormalizedTextView(ContentAddedMixIn, NotificationView):
+    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(NormalizedTextView, 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())
+
+
+class CardAddedView(NormalizedTextView):
+    """get notified from new cards"""
+    accepts = ('Card',)
+    content_attr = 'synopsis'
+    
+