def _register(watch_states, notifier, cb):
registered = []
try:
for s in watch_states:
if not notifier.is_registered(s, cb):
notifier.register(s, cb)
registered.append((s, cb))
except ValueError:
with excutils.save_and_reraise_exception():
for (s, cb) in registered:
notifier.deregister(s, cb)
def _bulk_register(watch_states, notifier, cb, details_filter=None):
"""Bulk registers a callback associated with many states."""
registered = []
try:
for state in watch_states:
if not notifier.is_registered(state, cb,
details_filter=details_filter):
notifier.register(state, cb,
details_filter=details_filter)
registered.append((state, cb))
except ValueError:
with excutils.save_and_reraise_exception():
_bulk_deregister(notifier, registered,
details_filter=details_filter)
else:
return registered
def _bulk_register(watch_states, notifier, cb, details_filter=None):
"""Bulk registers a callback associated with many states."""
registered = []
try:
for state in watch_states:
if not notifier.is_registered(state, cb,
details_filter=details_filter):
notifier.register(state, cb,
details_filter=details_filter)
registered.append((state, cb))
except ValueError:
with excutils.save_and_reraise_exception():
_bulk_deregister(notifier, registered,
details_filter=details_filter)
else:
return registered