hooks/notification.py
author Sylvain Thénault <sylvain.thenault@logilab.fr>
Tue, 21 Jun 2011 10:57:25 +0200
changeset 7543 570522300e22
parent 7068 90ddf608fe2b
child 7815 2a164a9cf81c
permissions -rw-r--r--
[ms, entity metas] add 'actual source' to entities table / base entity metadata cache. Closes #1767090 this is needed since for entities from 'copy based sources' such as datafeed, we want entity.cw_metainformation() to return as 'source' the datafeed source, not the system source (ie the source where the entity is actually stored). For both performance and bootstraping reasons, we should store this information in the `entities` table and in the _type_source cache.

# copyright 2003-2011 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
"""some hooks to handle notification on entity's changes"""

__docformat__ = "restructuredtext en"

from logilab.common.textutils import normalize_text

from cubicweb import RegistryNotFound
from cubicweb.selectors import is_instance
from cubicweb.server import hook
from cubicweb.sobjects.supervising import SupervisionMailOp

class RenderAndSendNotificationView(hook.Operation):
    """delay rendering of notification view until precommit"""
    def precommit_event(self):
        view = self.view
        if view.cw_rset is not None and not view.cw_rset:
            return # entity added and deleted in the same transaction (cache effect)
        if view.cw_rset and self.session.deleted_in_transaction(view.cw_rset[view.cw_row or 0][view.cw_col or 0]):
            return # entity added and deleted in the same transaction
        self.view.render_and_send(**getattr(self, 'viewargs', {}))


class NotificationHook(hook.Hook):
    __abstract__ = True
    category = 'notification'

    def select_view(self, vid, rset, row=0, col=0):
        try:
            return self._cw.vreg['views'].select_or_none(vid, self._cw, rset=rset,
                                                         row=row, col=col)
        except RegistryNotFound: # can happen in some config
                                 # (e.g. repo only config with no
                                 # notification views registered by
                                 # the instance's cubes)
            return None


class StatusChangeHook(NotificationHook):
    """notify when a workflowable entity has its state modified"""
    __regid__ = 'notifystatuschange'
    __select__ = NotificationHook.__select__ & is_instance('TrInfo')
    events = ('after_add_entity',)

    def __call__(self):
        entity = self.entity
        if not entity.from_state: # not a transition
            return
        rset = entity.related('wf_info_for')
        view = self.select_view('notif_status_change', rset=rset, row=0)
        if view is None:
            return
        comment = entity.printable_value('comment', format='text/plain')
        # XXX don't try to wrap rest until we've a proper transformation (see
        # #103822)
        if comment and entity.comment_format != 'text/rest':
            comment = normalize_text(comment, 80)
        RenderAndSendNotificationView(self._cw, view=view, viewargs={
            'comment': comment, 'previous_state': entity.previous_state.name,
            'current_state': entity.new_state.name})

class RelationChangeHook(NotificationHook):
    __regid__ = 'notifyrelationchange'
    events = ('before_add_relation', 'after_add_relation',
              'before_delete_relation', 'after_delete_relation')

    def __call__(self):
        """if a notification view is defined for the event, send notification
        email defined by the view
        """
        rset = self._cw.eid_rset(self.eidfrom)
        view = self.select_view('notif_%s_%s' % (self.event,  self.rtype),
                                rset=rset, row=0)
        if view is None:
            return
        RenderAndSendNotificationView(self._cw, view=view)


class EntityChangeHook(NotificationHook):
    """if a notification view is defined for the event, send notification
    email defined by the view
    """
    __regid__ = 'notifyentitychange'
    events = ('after_add_entity', 'after_update_entity')

    def __call__(self):
        rset = self.entity.as_rset()
        view = self.select_view('notif_%s' % self.event, rset=rset, row=0)
        if view is None:
            return
        RenderAndSendNotificationView(self._cw, view=view)


class EntityUpdatedNotificationOp(hook.SingleLastOperation):

    def precommit_event(self):
        session = self.session
        for eid in session.transaction_data['changes']:
            view = session.vreg['views'].select('notif_entity_updated', session,
                                                rset=session.eid_rset(eid),
                                                row=0)
            RenderAndSendNotificationView(session, view=view)


class EntityUpdateHook(NotificationHook):
    __regid__ = 'notifentityupdated'
    __abstract__ = True # do not register by default
    __select__ = NotificationHook.__select__ & hook.from_dbapi_query()
    events = ('before_update_entity',)
    skip_attrs = set()

    def __call__(self):
        session = self._cw
        if session.added_in_transaction(self.entity.eid):
            return # entity is being created
        # then compute changes
        attrs = [k for k in self.entity.cw_edited
                 if not k in self.skip_attrs]
        if not attrs:
            return
        changes = session.transaction_data.setdefault('changes', {})
        thisentitychanges = changes.setdefault(self.entity.eid, set())
        rqlsel, rqlrestr = [], ['X eid %(x)s']
        for i, attr in enumerate(attrs):
            var = chr(65+i)
            rqlsel.append(var)
            rqlrestr.append('X %s %s' % (attr, var))
        rql = 'Any %s WHERE %s' % (','.join(rqlsel), ','.join(rqlrestr))
        rset = session.execute(rql, {'x': self.entity.eid})
        for i, attr in enumerate(attrs):
            oldvalue = rset[0][i]
            newvalue = self.entity.cw_edited[attr]
            if oldvalue != newvalue:
                thisentitychanges.add((attr, oldvalue, newvalue))
        if thisentitychanges:
            EntityUpdatedNotificationOp(session)


# supervising ##################################################################

class SomethingChangedHook(NotificationHook):
    __regid__ = 'supervising'
    __select__ = NotificationHook.__select__ & hook.from_dbapi_query()
    events = ('before_add_relation', 'before_delete_relation',
              'after_add_entity', 'before_update_entity')

    def __call__(self):
        dest = self._cw.vreg.config['supervising-addrs']
        if not dest: # no supervisors, don't do this for nothing...
            return
        if self._call():
            SupervisionMailOp(self._cw)

    def _call(self):
        event = self.event.split('_', 1)[1]
        if event == 'update_entity':
            if self._cw.added_in_transaction(self.entity.eid):
                return False
            if self.entity.e_schema == 'CWUser':
                if not (frozenset(self.entity.cw_edited)
                        - frozenset(('eid', 'modification_date',
                                     'last_login_time'))):
                    # don't record last_login_time update which are done
                    # automatically at login time
                    return False
        self._cw.transaction_data.setdefault('pendingchanges', []).append(
            (event, self))
        return True


class EntityDeleteHook(SomethingChangedHook):
    __regid__ = 'supervisingentitydel'
    events = ('before_delete_entity',)

    def _call(self):
        try:
            title = self.entity.dc_title()
        except:
            # may raise an error during deletion process, for instance due to
            # missing required relation
            title = '#%s' % self.entity.eid
        self._cw.transaction_data.setdefault('pendingchanges', []).append(
            ('delete_entity', (self.entity.eid, self.entity.__regid__, title)))
        return True