Source code for keystone.openstack.common.eventlet_backdoor

# Copyright (c) 2012 OpenStack Foundation.
# Administrator of the National Aeronautics and Space Administration.
# All Rights Reserved.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

from __future__ import print_function

import errno
import gc
import os
import pprint
import socket
import sys
import traceback

import eventlet
import eventlet.backdoor
import greenlet
from oslo.config import cfg

from keystone.openstack.common.gettextutils import _  # noqa
from keystone.openstack.common import log as logging

help_for_backdoor_port = (
    "Acceptable values are 0, <port>, and <start>:<end>, where 0 results "
    "in listening on a random tcp port number; <port> results in listening "
    "on the specified port number (and not enabling backdoor if that port "
    "is in use); and <start>:<end> results in listening on the smallest "
    "unused port number within the specified range of port numbers.  The "
    "chosen port is displayed in the service's log file.")
eventlet_backdoor_opts = [
    cfg.StrOpt('backdoor_port',
               default=None,
               help="Enable eventlet backdoor.  %s" % help_for_backdoor_port)
]

CONF = cfg.CONF
CONF.register_opts(eventlet_backdoor_opts)
LOG = logging.getLogger(__name__)


[docs]class EventletBackdoorConfigValueError(Exception): def __init__(self, port_range, help_msg, ex): msg = ('Invalid backdoor_port configuration %(range)s: %(ex)s. ' '%(help)s' % {'range': port_range, 'ex': ex, 'help': help_msg}) super(EventletBackdoorConfigValueError, self).__init__(msg) self.port_range = port_range
def _dont_use_this(): print("Don't use this, just disconnect instead") def _find_objects(t): return filter(lambda o: isinstance(o, t), gc.get_objects()) def _print_greenthreads(): for i, gt in enumerate(_find_objects(greenlet.greenlet)): print(i, gt) traceback.print_stack(gt.gr_frame) print() def _print_nativethreads(): for threadId, stack in sys._current_frames().items(): print(threadId) traceback.print_stack(stack) print() def _parse_port_range(port_range): if ':' not in port_range: start, end = port_range, port_range else: start, end = port_range.split(':', 1) try: start, end = int(start), int(end) if end < start: raise ValueError return start, end except ValueError as ex: raise EventletBackdoorConfigValueError(port_range, ex, help_for_backdoor_port) def _listen(host, start_port, end_port, listen_func): try_port = start_port while True: try: return listen_func((host, try_port)) except socket.error as exc: if (exc.errno != errno.EADDRINUSE or try_port >= end_port): raise try_port += 1
[docs]def initialize_if_enabled(): backdoor_locals = { 'exit': _dont_use_this, # So we don't exit the entire process 'quit': _dont_use_this, # So we don't exit the entire process 'fo': _find_objects, 'pgt': _print_greenthreads, 'pnt': _print_nativethreads, } if CONF.backdoor_port is None: return None start_port, end_port = _parse_port_range(str(CONF.backdoor_port)) # NOTE(johannes): The standard sys.displayhook will print the value of # the last expression and set it to __builtin__._, which overwrites # the __builtin__._ that gettext sets. Let's switch to using pprint # since it won't interact poorly with gettext, and it's easier to # read the output too. def displayhook(val): if val is not None: pprint.pprint(val) sys.displayhook = displayhook sock = _listen('localhost', start_port, end_port, eventlet.listen) # In the case of backdoor port being zero, a port number is assigned by # listen(). In any case, pull the port number out here. port = sock.getsockname()[1] LOG.info(_('Eventlet backdoor listening on %(port)s for process %(pid)d') % {'port': port, 'pid': os.getpid()}) eventlet.spawn_n(eventlet.backdoor.backdoor_server, sock, locals=backdoor_locals) return port