def ssh_execute(ssh, cmd, process_input=None,
addl_env=None, check_exit_code=True):
sanitized_cmd = strutils.mask_password(cmd)
LOG.debug(_('Running cmd (SSH): %s'), sanitized_cmd)
if addl_env:
raise InvalidArgumentError(_('Environment not supported over SSH'))
if process_input:
# This is (probably) fixable if we need it...
raise InvalidArgumentError(_('process_input not supported over SSH'))
stdin_stream, stdout_stream, stderr_stream = ssh.exec_command(cmd)
channel = stdout_stream.channel
# NOTE(justinsb): This seems suspicious...
# ...other SSH clients have buffering issues with this approach
stdout = stdout_stream.read()
sanitized_stdout = strutils.mask_password(stdout)
stderr = stderr_stream.read()
sanitized_stderr = strutils.mask_password(stderr)
stdin_stream.close()
exit_status = channel.recv_exit_status()
# exit_status == -1 if no exit code was returned
if exit_status != -1:
LOG.debug(_('Result was %s') % exit_status)
if check_exit_code and exit_status != 0:
raise ProcessExecutionError(exit_code=exit_status,
stdout=sanitized_stdout,
stderr=sanitized_stderr,
cmd=sanitized_cmd)
return (sanitized_stdout, sanitized_stderr)
def inner(*args, **kwargs):
try:
with lock(name, lock_file_prefix, external, lock_path):
LOG.debug(_('Got semaphore / lock "%(function)s"'),
{'function': f.__name__})
return f(*args, **kwargs)
finally:
LOG.debug(_('Semaphore / lock released "%(function)s"'),
{'function': f.__name__})
def inner_func(*args, **kwargs):
last_log_time = 0
last_exc_message = None
exc_count = 0
while True:
try:
return infunc(*args, **kwargs)
except Exception as exc:
this_exc_message = six.u(str(exc))
if this_exc_message == last_exc_message:
exc_count += 1
else:
exc_count = 1
# Do not log any more frequently than once a minute unless
# the exception message changes
cur_time = int(time.time())
if (cur_time - last_log_time > 60 or
this_exc_message != last_exc_message):
logging.exception(
_('Unexpected exception occurred %d time(s)... '
'retrying.') % exc_count)
last_log_time = cur_time
last_exc_message = this_exc_message
exc_count = 0
# This should be a very rare event. In case it isn't, do
# a sleep.
time.sleep(1)
def __exit__(self, exc_type, exc_val, exc_tb):
try:
self.unlock()
self.lockfile.close()
except IOError:
LOG.exception(_("Could not release the acquired lock `%s`"),
self.fname)
def __init__(self, message=None, **kwargs):
self.kwargs = kwargs
if 'code' not in self.kwargs:
try:
self.kwargs['code'] = self.code
except AttributeError:
pass
if not message:
try:
message = self.message % kwargs
except Exception:
# kwargs doesn't match a variable in the message
# log the issue and the kwargs
msg = (_("Exception in string format operation. msg='%s'")
% self.message)
LOG.exception(msg)
for name, value in kwargs.iteritems():
LOG.error("%s: %s" % (name, value))
# at least get the core message out if something happened
message = self.message
# Put the message in 'msg' so that we can access it. If we have it in
# message it will be overshadowed by the class' message attribute
self.msg = message
super(VirtmanException, self).__init__(message)
def bool_from_string(subject, strict=False, default=False):
"""Interpret a string as a boolean.
A case-insensitive match is performed such that strings matching 't',
'true', 'on', 'y', 'yes', or '1' are considered True and, when
`strict=False`, anything else returns the value specified by 'default'.
Useful for JSON-decoded stuff and config file parsing.
If `strict=True`, unrecognized values, including None, will raise a
ValueError which is useful when parsing values passed in from an API call.
Strings yielding False are 'f', 'false', 'off', 'n', 'no', or '0'.
"""
if not isinstance(subject, six.string_types):
subject = str(subject)
lowered = subject.strip().lower()
if lowered in TRUE_STRINGS:
return True
elif lowered in FALSE_STRINGS:
return False
elif strict:
acceptable = ', '.join(
"'%s'" % s for s in sorted(TRUE_STRINGS + FALSE_STRINGS))
msg = _("Unrecognized value '%(val)s', acceptable values are:"
" %(acceptable)s") % {'val': subject,
'acceptable': acceptable}
raise ValueError(msg)
else:
return default
def deprecated(self, msg, *args, **kwargs):
"""Call this method when a deprecated feature is used.
If the system is configured for fatal deprecations then the message
is logged at the 'critical' level and :class:`DeprecatedConfig` will
be raised.
Otherwise, the message will be logged (once) at the 'warn' level.
:raises: :class:`DeprecatedConfig` if the system is configured for
fatal deprecations.
"""
stdmsg = _("Deprecated: %s") % msg
if CONF.fatal_deprecations:
self.critical(stdmsg, *args, **kwargs)
raise DeprecatedConfig(msg=stdmsg)
# Using a list because a tuple with dict can't be stored in a set.
sent_args = self._deprecated_messages_sent.setdefault(msg, list())
if args in sent_args:
# Already logged this message, so don't log it again.
return
sent_args.append(args)
self.warn(stdmsg, *args, **kwargs)
def __exit__(self, exc_type, exc_val, exc_tb):
if exc_type is not None:
logging.error(_('Original exception being dropped: %s'),
traceback.format_exception(self.type_,
self.value,
self.tb))
return False
if self.reraise:
six.reraise(self.type_, self.value, self.tb)
def string_to_bytes(text, unit_system='IEC', return_int=False):
"""Converts a string into an float representation of bytes.
The units supported for IEC ::
Kb(it), Kib(it), Mb(it), Mib(it), Gb(it), Gib(it), Tb(it), Tib(it)
KB, KiB, MB, MiB, GB, GiB, TB, TiB
The units supported for SI ::
kb(it), Mb(it), Gb(it), Tb(it)
kB, MB, GB, TB
Note that the SI unit system does not support capital letter 'K'
:param text: String input for bytes size conversion.
:param unit_system: Unit system for byte size conversion.
:param return_int: If True, returns integer representation of text
in bytes. (default: decimal)
:returns: Numerical representation of text in bytes.
:raises ValueError: If text has an invalid value.
"""
try:
base, reg_ex = UNIT_SYSTEM_INFO[unit_system]
except KeyError:
msg = _('Invalid unit system: "%s"') % unit_system
raise ValueError(msg)
match = reg_ex.match(text)
if match:
magnitude = float(match.group(1))
unit_prefix = match.group(2)
if match.group(3) in ['b', 'bit']:
magnitude /= 8
else:
msg = _('Invalid string format: %s') % text
raise ValueError(msg)
if not unit_prefix:
res = magnitude
else:
res = magnitude * pow(base, UNIT_PREFIX_EXPONENT[unit_prefix])
if return_int:
return int(math.ceil(res))
return res
def __init__(self, stdout=None, stderr=None, exit_code=None, cmd=None,
description=None):
self.exit_code = exit_code
self.stderr = stderr
self.stdout = stdout
self.cmd = cmd
self.description = description
if description is None:
description = _("Unexpected error while running command.")
if exit_code is None:
exit_code = '-'
message = _('%(description)s\n'
'Command: %(cmd)s\n'
'Exit code: %(exit_code)s\n'
'Stdout: %(stdout)r\n'
'Stderr: %(stderr)r') % {'description': description,
'cmd': cmd,
'exit_code': exit_code,
'stdout': stdout,
'stderr': stderr}
super(ProcessExecutionError, self).__init__(message)
def _find_facility_from_conf():
facility_names = logging.handlers.SysLogHandler.facility_names
facility = getattr(logging.handlers.SysLogHandler,
CONF.syslog_log_facility,
None)
if facility is None and CONF.syslog_log_facility in facility_names:
facility = facility_names.get(CONF.syslog_log_facility)
if facility is None:
valid_facilities = facility_names.keys()
consts = ['LOG_AUTH', 'LOG_AUTHPRIV', 'LOG_CRON', 'LOG_DAEMON',
'LOG_FTP', 'LOG_KERN', 'LOG_LPR', 'LOG_MAIL', 'LOG_NEWS',
'LOG_AUTH', 'LOG_SYSLOG', 'LOG_USER', 'LOG_UUCP',
'LOG_LOCAL0', 'LOG_LOCAL1', 'LOG_LOCAL2', 'LOG_LOCAL3',
'LOG_LOCAL4', 'LOG_LOCAL5', 'LOG_LOCAL6', 'LOG_LOCAL7']
valid_facilities.extend(consts)
raise TypeError(_('syslog facility must be one of: %s') %
', '.join("'%s'" % fac
for fac in valid_facilities))
return facility
def read_cached_file(filename, force_reload=False):
"""Read from a file if it has been modified.
:param force_reload: Whether to reload the file.
:returns: A tuple with a boolean specifying if the data is fresh
or not.
"""
global _FILE_CACHE
if force_reload and filename in _FILE_CACHE:
del _FILE_CACHE[filename]
reloaded = False
mtime = os.path.getmtime(filename)
cache_info = _FILE_CACHE.setdefault(filename, {})
if not cache_info or mtime > cache_info.get("mtime", 0):
LOG.debug(_("Reloading cached file %s") % filename)
with open(filename) as fap:
cache_info["data"] = fap.read()
cache_info["mtime"] = mtime
reloaded = True
return (reloaded, cache_info["data"])
def lock(name, lock_file_prefix=None, external=False, lock_path=None):
"""Context based lock
This function yields a `threading.Semaphore` instance (if we don't use
eventlet.monkey_patch(), else `semaphore.Semaphore`) unless external is
True, in which case, it'll yield an InterProcessLock instance.
:param lock_file_prefix: The lock_file_prefix argument is used to provide
lock files on disk with a meaningful prefix.
:param external: The external keyword argument denotes whether this lock
should work across multiple processes. This means that if two different
workers both run a a method decorated with @synchronized('mylock',
external=True), only one of them will execute at a time.
:param lock_path: The lock_path keyword argument is used to specify a
special location for external lock files to live. If nothing is set, then
CONF.lock_path is used as a default.
"""
with _semaphores_lock:
try:
sem = _semaphores[name]
except KeyError:
sem = threading.Semaphore()
_semaphores[name] = sem
with sem:
LOG.debug(_('Got semaphore "%(lock)s"'), {'lock': name})
# NOTE(mikal): I know this looks odd
if not hasattr(local.strong_store, 'locks_held'):
local.strong_store.locks_held = []
local.strong_store.locks_held.append(name)
try:
if external and not CONF.disable_process_locking:
LOG.debug(_('Attempting to grab file lock "%(lock)s"'),
{'lock': name})
# We need a copy of lock_path because it is non-local
local_lock_path = lock_path or CONF.lock_path
if not local_lock_path:
raise cfg.RequiredOptError('lock_path')
if not os.path.exists(local_lock_path):
fileutils.ensure_tree(local_lock_path)
LOG.info(_('Created lock path: %s'), local_lock_path)
def add_prefix(name, prefix):
if not prefix:
return name
sep = '' if prefix.endswith('-') else '-'
return '%s%s%s' % (prefix, sep, name)
# NOTE(mikal): the lock name cannot contain directory
# separators
lock_file_name = add_prefix(name.replace(os.sep, '_'),
lock_file_prefix)
lock_file_path = os.path.join(local_lock_path, lock_file_name)
try:
lock = InterProcessLock(lock_file_path)
with lock as lock:
LOG.debug(_('Got file lock "%(lock)s" at %(path)s'),
{'lock': name, 'path': lock_file_path})
yield lock
finally:
LOG.debug(_('Released file lock "%(lock)s" at %(path)s'),
{'lock': name, 'path': lock_file_path})
else:
yield sem
finally:
local.strong_store.locks_held.remove(name)
def execute(*cmd, **kwargs):
"""Helper method to shell out and execute a command through subprocess.
Allows optional retry.
:param cmd: Passed to subprocess.Popen.
:type cmd: string
:param process_input: Send to opened process.
:type proces_input: string
:param check_exit_code: Single bool, int, or list of allowed exit
codes. Defaults to [0]. Raise
:class:`ProcessExecutionError` unless
program exits with one of these code.
:type check_exit_code: boolean, int, or [int]
:param delay_on_retry: True | False. Defaults to True. If set to True,
wait a short amount of time before retrying.
:type delay_on_retry: boolean
:param attempts: How many times to retry cmd.
:type attempts: int
:param run_as_root: True | False. Defaults to False. If set to True,
the command is prefixed by the command specified
in the root_helper kwarg.
:type run_as_root: boolean
:param root_helper: command to prefix to commands called with
run_as_root=True
:type root_helper: string
:param shell: whether or not there should be a shell used to
execute this command. Defaults to false.
:type shell: boolean
:param loglevel: log level for execute commands.
:type loglevel: int. (Should be logging.DEBUG or logging.INFO)
:returns: (stdout, stderr) from process execution
:raises: :class:`UnknownArgumentError` on
receiving unknown arguments
:raises: :class:`ProcessExecutionError`
"""
process_input = kwargs.pop('process_input', None)
check_exit_code = kwargs.pop('check_exit_code', [0])
ignore_exit_code = False
delay_on_retry = kwargs.pop('delay_on_retry', True)
attempts = kwargs.pop('attempts', 1)
run_as_root = kwargs.pop('run_as_root', False)
root_helper = kwargs.pop('root_helper', '')
shell = kwargs.pop('shell', False)
loglevel = kwargs.pop('loglevel', logging.DEBUG)
if isinstance(check_exit_code, bool):
ignore_exit_code = not check_exit_code
check_exit_code = [0]
elif isinstance(check_exit_code, int):
check_exit_code = [check_exit_code]
if kwargs:
raise UnknownArgumentError(_('Got unknown keyword args '
'to utils.execute: %r') % kwargs)
if run_as_root and hasattr(os, 'geteuid') and os.geteuid() != 0:
if not root_helper:
raise NoRootWrapSpecified(
message=('Command requested root, but did not specify a root '
'helper.'))
cmd = shlex.split(root_helper) + list(cmd)
cmd = map(str, cmd)
sanitized_cmd = strutils.mask_password(' '.join(cmd))
while attempts > 0:
attempts -= 1
try:
LOG.log(loglevel, _('Running cmd (subprocess): %s'), sanitized_cmd)
_PIPE = subprocess.PIPE # pylint: disable=E1101
if os.name == 'nt':
preexec_fn = None
close_fds = False
else:
preexec_fn = _subprocess_setup
close_fds = True
obj = subprocess.Popen(cmd,
stdin=_PIPE,
stdout=_PIPE,
stderr=_PIPE,
close_fds=close_fds,
preexec_fn=preexec_fn,
shell=shell)
result = None
if process_input is not None:
result = obj.communicate(process_input)
else:
result = obj.communicate()
obj.stdin.close() # pylint: disable=E1101
_returncode = obj.returncode # pylint: disable=E1101
LOG.log(loglevel, _('Result was %s') % _returncode)
if not ignore_exit_code and _returncode not in check_exit_code:
(stdout, stderr) = result
sanitized_stdout = strutils.mask_password(stdout)
sanitized_stderr = strutils.mask_password(stderr)
raise ProcessExecutionError(exit_code=_returncode,
stdout=sanitized_stdout,
stderr=sanitized_stderr,
cmd=sanitized_cmd)
return result
except ProcessExecutionError:
if not attempts:
raise
else:
LOG.log(loglevel, _('%r failed. Retrying.'), sanitized_cmd)
if delay_on_retry:
greenthread.sleep(random.randint(20, 200) / 100.0)
finally:
# NOTE(termie): this appears to be necessary to let the subprocess
# call clean something up in between calls, without
# it two execute calls in a row hangs the second one
greenthread.sleep(0)
