def inner(*args, **kwargs):
with lock(name, lock_file_prefix, external, lock_path):
LOG.debug(_('Got semaphore / lock "%(function)s"'),
{'function': f.__name__})
return f(*args, **kwargs)
LOG.debug(_('Semaphore / lock released "%(function)s"'),
{'function': f.__name__})
def inner(*args, **kwargs):
with lock(name, lock_file_prefix, external, lock_path):
LOG.debug(_('Got semaphore / lock "%(function)s"'),
{'function': f.__name__})
return f(*args, **kwargs)
LOG.debug(_('Semaphore / lock released "%(function)s"'),
{'function': f.__name__})
def deprecated(self, msg, *args, **kwargs):
stdmsg = _("Deprecated: %s") % msg
if CONF.fatal_deprecations:
self.critical(stdmsg, *args, **kwargs)
raise DeprecatedConfig(msg=stdmsg)
else:
self.warn(stdmsg, *args, **kwargs)
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 = unicode(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 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 = six.text_type(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 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 = six.text_type(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 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 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):
try:
self.unlock()
self.lockfile.close()
except IOError:
LOG.exception(_("Could not release the acquired lock `%s`"),
self.fname)
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):
try:
self.unlock()
self.lockfile.close()
except IOError:
LOG.exception(_("Could not release the acquired lock `%s`"),
self.fname)
def deprecated(self, msg, *args, **kwargs):
stdmsg = _("Deprecated: %s") % msg
if CONF.fatal_deprecations:
self.critical(stdmsg, *args, **kwargs)
raise DeprecatedConfig(msg=stdmsg)
else:
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 __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 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
class LogConfigError(Exception):
message = _('Error loading logging config %(log_config)s: %(err_msg)s')
def __init__(self, log_config, err_msg):
self.log_config = log_config
self.err_msg = err_msg
def __str__(self):
return self.message % dict(log_config=self.log_config,
err_msg=self.err_msg)
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 _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 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.
"""
# NOTE(soren): If we ever go natively threaded, this will be racy.
# See http://stackoverflow.com/questions/5390569/dyn
# amically-allocating-and-destroying-mutexes
sem = _semaphores.get(name, threading.Semaphore())
if name not in _semaphores:
# this check is not racy - we're already holding ref locally
# so GC won't remove the item and there was no IO switch
# (only valid in greenthreads)
_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)
class DeprecatedConfig(Exception):
message = _("Fatal call to deprecated config: %(msg)s")
def __init__(self, msg):
super(Exception, self).__init__(self.message % dict(msg=msg))
class deprecated(object):
"""A decorator to mark callables as deprecated.
This decorator logs a deprecation message when the callable it decorates is
used. The message will include the release where the callable was
deprecated, the release where it may be removed and possibly an optional
replacement.
Examples:
1. Specifying the required deprecated release
>>> @deprecated(as_of=deprecated.ICEHOUSE)
... def a(): pass
2. Specifying a replacement:
>>> @deprecated(as_of=deprecated.ICEHOUSE, in_favor_of='f()')
... def b(): pass
3. Specifying the release where the functionality may be removed:
>>> @deprecated(as_of=deprecated.ICEHOUSE, remove_in=+1)
... def c(): pass
"""
FOLSOM = 'F'
GRIZZLY = 'G'
HAVANA = 'H'
ICEHOUSE = 'I'
_RELEASES = {
'F': 'Folsom',
'G': 'Grizzly',
'H': 'Havana',
'I': 'Icehouse',
}
_deprecated_msg_with_alternative = _(
'%(what)s is deprecated as of %(as_of)s in favor of '
'%(in_favor_of)s and may be removed in %(remove_in)s.')
_deprecated_msg_no_alternative = _(
'%(what)s is deprecated as of %(as_of)s and may be '
'removed in %(remove_in)s. It will not be superseded.')
def __init__(self, as_of, in_favor_of=None, remove_in=2, what=None):
"""Initialize decorator
:param as_of: the release deprecating the callable. Constants
are define in this class for convenience.
:param in_favor_of: the replacement for the callable (optional)
:param remove_in: an integer specifying how many releases to wait
before removing (default: 2)
:param what: name of the thing being deprecated (default: the
callable's name)
"""
self.as_of = as_of
self.in_favor_of = in_favor_of
self.remove_in = remove_in
self.what = what
def __call__(self, func):
if not self.what:
self.what = func.__name__ + '()'
@functools.wraps(func)
def wrapped(*args, **kwargs):
msg, details = self._build_message()
LOG.deprecated(msg, details)
return func(*args, **kwargs)
return wrapped
def _get_safe_to_remove_release(self, release):
# TODO(dstanek): this method will have to be reimplemented once
# when we get to the X release because once we get to the Y
# release, what is Y+2?
new_release = chr(ord(release) + self.remove_in)
if new_release in self._RELEASES:
return self._RELEASES[new_release]
else:
return new_release
def _build_message(self):
details = dict(what=self.what,
as_of=self._RELEASES[self.as_of],
remove_in=self._get_safe_to_remove_release(self.as_of))
if self.in_favor_of:
details['in_favor_of'] = self.in_favor_of
msg = self._deprecated_msg_with_alternative
else:
msg = self._deprecated_msg_no_alternative
return msg, details
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.
"""
# NOTE(soren): If we ever go natively threaded, this will be racy.
# See http://stackoverflow.com/questions/5390569/dyn
# amically-allocating-and-destroying-mutexes
sem = _semaphores.get(name, threading.Semaphore())
if name not in _semaphores:
# this check is not racy - we're already holding ref locally
# so GC won't remove the item and there was no IO switch
# (only valid in greenthreads)
_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)
