[repo] Add a publish/subscribe mechanism for inter-instance communication using zmq
Each repo can have a publishing and any number of subscribing sockets
whose addresses are specified in the instance's configuration. An
application or cube can subscribe to some 'topics', and give a callback
that gets called when a message matching that topic is received.
As a proof of concept, this introduces a hook to clean up the caches
associated with the repository when an entity is deleted.
A subscription is added using Repository::zmq::add_subscription;
the callback receives a list representing the received multi-part
message as argument (the first element of the message is its topic).
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"""bookmark related hooks"""
__docformat__ = "restructuredtext en"
from cubicweb.server import hook
class AutoDeleteBookmarkOp(hook.Operation):
bookmark = None # make pylint happy
def precommit_event(self):
if not self.session.deleted_in_transaction(self.bookmark.eid):
if not self.bookmark.bookmarked_by:
self.bookmark.cw_delete()
class DelBookmarkedByHook(hook.Hook):
"""ensure user logins are stripped"""
__regid__ = 'autodelbookmark'
__select__ = hook.Hook.__select__ & hook.match_rtype('bookmarked_by',)
category = 'bookmark'
events = ('after_delete_relation',)
def __call__(self):
AutoDeleteBookmarkOp(self._cw,
bookmark=self._cw.entity_from_eid(self.eidfrom))