# copyright 2019 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact https://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 <https://www.gnu.org/licenses/>.
from logging import getLogger
logger = getLogger("cubicweb")
SUBSCRIBERS = {
"controller": [],
"rql": [],
"sql": [],
"vreg": [],
"registry_decisions": [],
}
def debug_channel_has_subscribers(channel):
return len(SUBSCRIBERS.get(channel, [])) > 0
[docs]def subscribe_to_debug_channel(channel, subscriber):
"""
Allow to subscribe a callable to one of the debug channels.
The channel must be one of: %s
And the callable need to accept one argument.
It will raise Exception if the channel doesn't exist.
""" % SUBSCRIBERS.keys()
if channel not in SUBSCRIBERS.keys():
raise Exception("debug channel '%s' doesn't exist" % channel)
SUBSCRIBERS[channel].append(subscriber)
[docs]def unsubscribe_to_debug_channel(channel, subscriber):
"""
Unsubscribe a callable from a channel. It will raise Exception if the
channel doesn't exist nor
"""
if channel not in SUBSCRIBERS.keys():
raise Exception("debug channel '%s' doesn't exist" % channel)
if subscriber not in SUBSCRIBERS[channel]:
raise Exception(
f"subscriber '{subscriber}' is not in debug channel '{channel}'"
)
SUBSCRIBERS[channel].remove(subscriber)
def emit_to_debug_channel(channel, message):
"""
Send a message to a specified debug channel that will call all its
subscribers.
It will raise Exception if the channel doesn't exist.
"""
if channel not in SUBSCRIBERS.keys():
raise Exception("debug channel '%s' doesn't exist" % channel)
for subscriber in SUBSCRIBERS[channel]:
try:
subscriber(message)
except Exception:
logger.error(
"Failed to send debug message '%s' to subscriber '%s'",
message,
subscriber,
exc_info=True,
)
