os-brick/os_brick/executor.py
Gorka Eguileor 32ab0d1670 iSCSI multipath: improve logging on connect
The new iSCSI multipath code uses multithreading to do the connections,
but since the context is a thread local variable it will not be present
in those threads so we will not see the request id or other information
from the context in those thread's log entries.

This is a small inconvenience when looking at the logs if we try to
filter by the request id,.

To resolve this we introduce a new Thread class that inherits the
context from the calling thread, this way any log entries will have the
right context and present expected information.

Change-Id: I27624a59738809d30531c0c4f37308f897dd9654
2017-06-26 20:31:59 +02:00

85 lines
2.9 KiB
Python

# (c) Copyright 2013 Hewlett-Packard Development Company, L.P.
#
# 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.
"""Generic exec utility that allows us to set the
execute and root_helper attributes for putils.
Some projects need their own execute wrapper
and root_helper settings, so this provides that hook.
"""
import threading
from oslo_concurrency import processutils as putils
from oslo_context import context as context_utils
from oslo_utils import encodeutils
from os_brick.privileged import rootwrap as priv_rootwrap
class Executor(object):
def __init__(self, root_helper, execute=None,
*args, **kwargs):
if execute is None:
execute = priv_rootwrap.execute
self.set_execute(execute)
self.set_root_helper(root_helper)
@staticmethod
def safe_decode(string):
return string and encodeutils.safe_decode(string, errors='ignore')
@classmethod
def make_putils_error_safe(cls, exc):
"""Converts ProcessExecutionError string attributes to unicode."""
for field in ('stderr', 'stdout', 'cmd', 'description'):
value = getattr(exc, field, None)
if value:
setattr(exc, field, cls.safe_decode(value))
def _execute(self, *args, **kwargs):
try:
result = self.__execute(*args, **kwargs)
if result:
result = (self.safe_decode(result[0]),
self.safe_decode(result[1]))
return result
except putils.ProcessExecutionError as e:
self.make_putils_error_safe(e)
raise
def set_execute(self, execute):
self.__execute = execute
def set_root_helper(self, helper):
self._root_helper = helper
class Thread(threading.Thread):
"""Thread class that inherits the parent's context.
This is useful when you are spawning a thread and want LOG entries to
display the right context information, such as the request.
"""
def __init__(self, *args, **kwargs):
# Store the caller's context as a private variable shared among threads
self.__context__ = context_utils.get_current()
super(Thread, self).__init__(*args, **kwargs)
def run(self):
# Store the context in the current thread's request store
if self.__context__:
self.__context__.update_store()
super(Thread, self).run()