cpython/Lib/logging/config.py

868 lines
32 KiB
Python

# Copyright 2001-2010 by Vinay Sajip. All Rights Reserved.
#
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose and without fee is hereby granted,
# provided that the above copyright notice appear in all copies and that
# both that copyright notice and this permission notice appear in
# supporting documentation, and that the name of Vinay Sajip
# not be used in advertising or publicity pertaining to distribution
# of the software without specific, written prior permission.
# VINAY SAJIP DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
# ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
# VINAY SAJIP BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
# ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
# IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
"""
Configuration functions for the logging package for Python. The core package
is based on PEP 282 and comments thereto in comp.lang.python, and influenced
by Apache's log4j system.
Copyright (C) 2001-2010 Vinay Sajip. All Rights Reserved.
To use, simply 'import logging' and log away!
"""
import sys, logging, logging.handlers, socket, struct, os, traceback, re
import types, cStringIO
try:
import thread
import threading
except ImportError:
thread = None
from SocketServer import ThreadingTCPServer, StreamRequestHandler
DEFAULT_LOGGING_CONFIG_PORT = 9030
if sys.platform == "win32":
RESET_ERROR = 10054 #WSAECONNRESET
else:
RESET_ERROR = 104 #ECONNRESET
#
# The following code implements a socket listener for on-the-fly
# reconfiguration of logging.
#
# _listener holds the server object doing the listening
_listener = None
def fileConfig(fname, defaults=None, disable_existing_loggers=True):
"""
Read the logging configuration from a ConfigParser-format file.
This can be called several times from an application, allowing an end user
the ability to select from various pre-canned configurations (if the
developer provides a mechanism to present the choices and load the chosen
configuration).
In versions of ConfigParser which have the readfp method [typically
shipped in 2.x versions of Python], you can pass in a file-like object
rather than a filename, in which case the file-like object will be read
using readfp.
"""
import ConfigParser
cp = ConfigParser.ConfigParser(defaults)
if hasattr(cp, 'readfp') and hasattr(fname, 'readline'):
cp.readfp(fname)
else:
cp.read(fname)
formatters = _create_formatters(cp)
# critical section
logging._acquireLock()
try:
logging._handlers.clear()
del logging._handlerList[:]
# Handlers add themselves to logging._handlers
handlers = _install_handlers(cp, formatters)
_install_loggers(cp, handlers, disable_existing_loggers)
finally:
logging._releaseLock()
def _resolve(name):
"""Resolve a dotted name to a global object."""
name = name.split('.')
used = name.pop(0)
found = __import__(used)
for n in name:
used = used + '.' + n
try:
found = getattr(found, n)
except AttributeError:
__import__(used)
found = getattr(found, n)
return found
def _strip_spaces(alist):
return map(lambda x: x.strip(), alist)
def _create_formatters(cp):
"""Create and return formatters"""
flist = cp.get("formatters", "keys")
if not len(flist):
return {}
flist = flist.split(",")
flist = _strip_spaces(flist)
formatters = {}
for form in flist:
sectname = "formatter_%s" % form
opts = cp.options(sectname)
if "format" in opts:
fs = cp.get(sectname, "format", 1)
else:
fs = None
if "datefmt" in opts:
dfs = cp.get(sectname, "datefmt", 1)
else:
dfs = None
c = logging.Formatter
if "class" in opts:
class_name = cp.get(sectname, "class")
if class_name:
c = _resolve(class_name)
f = c(fs, dfs)
formatters[form] = f
return formatters
def _install_handlers(cp, formatters):
"""Install and return handlers"""
hlist = cp.get("handlers", "keys")
if not len(hlist):
return {}
hlist = hlist.split(",")
hlist = _strip_spaces(hlist)
handlers = {}
fixups = [] #for inter-handler references
for hand in hlist:
sectname = "handler_%s" % hand
klass = cp.get(sectname, "class")
opts = cp.options(sectname)
if "formatter" in opts:
fmt = cp.get(sectname, "formatter")
else:
fmt = ""
try:
klass = eval(klass, vars(logging))
except (AttributeError, NameError):
klass = _resolve(klass)
args = cp.get(sectname, "args")
args = eval(args, vars(logging))
h = klass(*args)
if "level" in opts:
level = cp.get(sectname, "level")
h.setLevel(logging._levelNames[level])
if len(fmt):
h.setFormatter(formatters[fmt])
if issubclass(klass, logging.handlers.MemoryHandler):
if "target" in opts:
target = cp.get(sectname,"target")
else:
target = ""
if len(target): #the target handler may not be loaded yet, so keep for later...
fixups.append((h, target))
handlers[hand] = h
#now all handlers are loaded, fixup inter-handler references...
for h, t in fixups:
h.setTarget(handlers[t])
return handlers
def _install_loggers(cp, handlers, disable_existing_loggers):
"""Create and install loggers"""
# configure the root first
llist = cp.get("loggers", "keys")
llist = llist.split(",")
llist = list(map(lambda x: x.strip(), llist))
llist.remove("root")
sectname = "logger_root"
root = logging.root
log = root
opts = cp.options(sectname)
if "level" in opts:
level = cp.get(sectname, "level")
log.setLevel(logging._levelNames[level])
for h in root.handlers[:]:
root.removeHandler(h)
hlist = cp.get(sectname, "handlers")
if len(hlist):
hlist = hlist.split(",")
hlist = _strip_spaces(hlist)
for hand in hlist:
log.addHandler(handlers[hand])
#and now the others...
#we don't want to lose the existing loggers,
#since other threads may have pointers to them.
#existing is set to contain all existing loggers,
#and as we go through the new configuration we
#remove any which are configured. At the end,
#what's left in existing is the set of loggers
#which were in the previous configuration but
#which are not in the new configuration.
existing = list(root.manager.loggerDict.keys())
#The list needs to be sorted so that we can
#avoid disabling child loggers of explicitly
#named loggers. With a sorted list it is easier
#to find the child loggers.
existing.sort()
#We'll keep the list of existing loggers
#which are children of named loggers here...
child_loggers = []
#now set up the new ones...
for log in llist:
sectname = "logger_%s" % log
qn = cp.get(sectname, "qualname")
opts = cp.options(sectname)
if "propagate" in opts:
propagate = cp.getint(sectname, "propagate")
else:
propagate = 1
logger = logging.getLogger(qn)
if qn in existing:
i = existing.index(qn)
prefixed = qn + "."
pflen = len(prefixed)
num_existing = len(existing)
i = i + 1 # look at the entry after qn
while (i < num_existing) and (existing[i][:pflen] == prefixed):
child_loggers.append(existing[i])
i = i + 1
existing.remove(qn)
if "level" in opts:
level = cp.get(sectname, "level")
logger.setLevel(logging._levelNames[level])
for h in logger.handlers[:]:
logger.removeHandler(h)
logger.propagate = propagate
logger.disabled = 0
hlist = cp.get(sectname, "handlers")
if len(hlist):
hlist = hlist.split(",")
hlist = _strip_spaces(hlist)
for hand in hlist:
logger.addHandler(handlers[hand])
#Disable any old loggers. There's no point deleting
#them as other threads may continue to hold references
#and by disabling them, you stop them doing any logging.
#However, don't disable children of named loggers, as that's
#probably not what was intended by the user.
for log in existing:
logger = root.manager.loggerDict[log]
if log in child_loggers:
logger.level = logging.NOTSET
logger.handlers = []
logger.propagate = 1
elif disable_existing_loggers:
logger.disabled = 1
IDENTIFIER = re.compile('^[a-z_][a-z0-9_]*$', re.I)
def valid_ident(s):
m = IDENTIFIER.match(s)
if not m:
raise ValueError('Not a valid Python identifier: %r' % s)
return True
# The ConvertingXXX classes are wrappers around standard Python containers,
# and they serve to convert any suitable values in the container. The
# conversion converts base dicts, lists and tuples to their wrapped
# equivalents, whereas strings which match a conversion format are converted
# appropriately.
#
# Each wrapper should have a configurator attribute holding the actual
# configurator to use for conversion.
class ConvertingDict(dict):
"""A converting dictionary wrapper."""
def __getitem__(self, key):
value = dict.__getitem__(self, key)
result = self.configurator.convert(value)
#If the converted value is different, save for next time
if value is not result:
self[key] = result
if type(result) in (ConvertingDict, ConvertingList,
ConvertingTuple):
result.parent = self
result.key = key
return result
def get(self, key, default=None):
value = dict.get(self, key, default)
result = self.configurator.convert(value)
#If the converted value is different, save for next time
if value is not result:
self[key] = result
if type(result) in (ConvertingDict, ConvertingList,
ConvertingTuple):
result.parent = self
result.key = key
return result
def pop(self, key, default=None):
value = dict.pop(self, key, default)
result = self.configurator.convert(value)
if value is not result:
if type(result) in (ConvertingDict, ConvertingList,
ConvertingTuple):
result.parent = self
result.key = key
return result
class ConvertingList(list):
"""A converting list wrapper."""
def __getitem__(self, key):
value = list.__getitem__(self, key)
result = self.configurator.convert(value)
#If the converted value is different, save for next time
if value is not result:
self[key] = result
if type(result) in (ConvertingDict, ConvertingList,
ConvertingTuple):
result.parent = self
result.key = key
return result
def pop(self, idx=-1):
value = list.pop(self, idx)
result = self.configurator.convert(value)
if value is not result:
if type(result) in (ConvertingDict, ConvertingList,
ConvertingTuple):
result.parent = self
return result
class ConvertingTuple(tuple):
"""A converting tuple wrapper."""
def __getitem__(self, key):
value = tuple.__getitem__(self, key)
result = self.configurator.convert(value)
if value is not result:
if type(result) in (ConvertingDict, ConvertingList,
ConvertingTuple):
result.parent = self
result.key = key
return result
class BaseConfigurator(object):
"""
The configurator base class which defines some useful defaults.
"""
CONVERT_PATTERN = re.compile(r'^(?P<prefix>[a-z]+)://(?P<suffix>.*)$')
WORD_PATTERN = re.compile(r'^\s*(\w+)\s*')
DOT_PATTERN = re.compile(r'^\.\s*(\w+)\s*')
INDEX_PATTERN = re.compile(r'^\[\s*(\w+)\s*\]\s*')
DIGIT_PATTERN = re.compile(r'^\d+$')
value_converters = {
'ext' : 'ext_convert',
'cfg' : 'cfg_convert',
}
# We might want to use a different one, e.g. importlib
importer = __import__
def __init__(self, config):
self.config = ConvertingDict(config)
self.config.configurator = self
def resolve(self, s):
"""
Resolve strings to objects using standard import and attribute
syntax.
"""
name = s.split('.')
used = name.pop(0)
found = self.importer(used)
for frag in name:
used += '.' + frag
try:
found = getattr(found, frag)
except AttributeError:
self.importer(used)
found = getattr(found, frag)
return found
def ext_convert(self, value):
"""Default converter for the ext:// protocol."""
return self.resolve(value)
def cfg_convert(self, value):
"""Default converter for the cfg:// protocol."""
rest = value
m = self.WORD_PATTERN.match(rest)
if m is None:
raise ValueError("Unable to convert %r" % value)
else:
rest = rest[m.end():]
d = self.config[m.groups()[0]]
#print d, rest
while rest:
m = self.DOT_PATTERN.match(rest)
if m:
d = d[m.groups()[0]]
else:
m = self.INDEX_PATTERN.match(rest)
if m:
idx = m.groups()[0]
if not self.DIGIT_PATTERN.match(idx):
d = d[idx]
else:
try:
n = int(idx) # try as number first (most likely)
d = d[n]
except TypeError:
d = d[idx]
if m:
rest = rest[m.end():]
else:
raise ValueError('Unable to convert '
'%r at %r' % (value, rest))
#rest should be empty
return d
def convert(self, value):
"""
Convert values to an appropriate type. dicts, lists and tuples are
replaced by their converting alternatives. Strings are checked to
see if they have a conversion format and are converted if they do.
"""
if not isinstance(value, ConvertingDict) and isinstance(value, dict):
value = ConvertingDict(value)
value.configurator = self
elif not isinstance(value, ConvertingList) and isinstance(value, list):
value = ConvertingList(value)
value.configurator = self
elif not isinstance(value, ConvertingTuple) and\
isinstance(value, tuple):
value = ConvertingTuple(value)
value.configurator = self
elif isinstance(value, basestring): # str for py3k
m = self.CONVERT_PATTERN.match(value)
if m:
d = m.groupdict()
prefix = d['prefix']
converter = self.value_converters.get(prefix, None)
if converter:
suffix = d['suffix']
converter = getattr(self, converter)
value = converter(suffix)
return value
def configure_custom(self, config):
"""Configure an object with a user-supplied factory."""
c = config.pop('()')
if not hasattr(c, '__call__') and hasattr(types, 'ClassType') and type(c) != types.ClassType:
c = self.resolve(c)
props = config.pop('.', None)
# Check for valid identifiers
kwargs = dict([(k, config[k]) for k in config if valid_ident(k)])
result = c(**kwargs)
if props:
for name, value in props.items():
setattr(result, name, value)
return result
class DictConfigurator(BaseConfigurator):
"""
Configure logging using a dictionary-like object to describe the
configuration.
"""
def configure(self):
"""Do the configuration."""
config = self.config
incremental = config.pop('incremental', False)
EMPTY_DICT = {}
logging._acquireLock()
try:
if incremental:
handlers = config.get('handlers', EMPTY_DICT)
for name in handlers:
if name not in logging._handlers:
raise ValueError('No handler found with '
'name %r' % name)
else:
try:
handler = logging._handlers[name]
handler_config = handlers[name]
level = handler_config.get('level', None)
if level:
handler.setLevel(logging._checkLevel(level))
except StandardError, e:
raise ValueError('Unable to configure handler '
'%r: %s' % (name, e))
loggers = config.get('loggers', EMPTY_DICT)
for name in loggers:
try:
self.configure_logger(name, loggers[name], True)
except StandardError, e:
raise ValueError('Unable to configure logger '
'%r: %s' % (name, e))
root = config.get('root', None)
if root:
try:
self.configure_root(root, True)
except StandardError, e:
raise ValueError('Unable to configure root '
'logger: %s' % e)
else:
disable_existing = config.pop('disable_existing_loggers', True)
logging._handlers.clear()
del logging._handlerList[:]
# Do formatters first - they don't refer to anything else
formatters = config.get('formatters', EMPTY_DICT)
for name in formatters:
try:
formatters[name] = self.configure_formatter(
formatters[name])
except StandardError, e:
raise ValueError('Unable to configure '
'formatter %r: %s' % (name, e))
# Next, do filters - they don't refer to anything else, either
filters = config.get('filters', EMPTY_DICT)
for name in filters:
try:
filters[name] = self.configure_filter(filters[name])
except StandardError, e:
raise ValueError('Unable to configure '
'filter %r: %s' % (name, e))
# Next, do handlers - they refer to formatters and filters
# As handlers can refer to other handlers, sort the keys
# to allow a deterministic order of configuration
handlers = config.get('handlers', EMPTY_DICT)
for name in sorted(handlers):
try:
handler = self.configure_handler(handlers[name])
handler.name = name
handlers[name] = handler
except StandardError, e:
raise ValueError('Unable to configure handler '
'%r: %s' % (name, e))
# Next, do loggers - they refer to handlers and filters
#we don't want to lose the existing loggers,
#since other threads may have pointers to them.
#existing is set to contain all existing loggers,
#and as we go through the new configuration we
#remove any which are configured. At the end,
#what's left in existing is the set of loggers
#which were in the previous configuration but
#which are not in the new configuration.
root = logging.root
existing = root.manager.loggerDict.keys()
#The list needs to be sorted so that we can
#avoid disabling child loggers of explicitly
#named loggers. With a sorted list it is easier
#to find the child loggers.
existing.sort()
#We'll keep the list of existing loggers
#which are children of named loggers here...
child_loggers = []
#now set up the new ones...
loggers = config.get('loggers', EMPTY_DICT)
for name in loggers:
if name in existing:
i = existing.index(name)
prefixed = name + "."
pflen = len(prefixed)
num_existing = len(existing)
i = i + 1 # look at the entry after name
while (i < num_existing) and\
(existing[i][:pflen] == prefixed):
child_loggers.append(existing[i])
i = i + 1
existing.remove(name)
try:
self.configure_logger(name, loggers[name])
except StandardError, e:
raise ValueError('Unable to configure logger '
'%r: %s' % (name, e))
#Disable any old loggers. There's no point deleting
#them as other threads may continue to hold references
#and by disabling them, you stop them doing any logging.
#However, don't disable children of named loggers, as that's
#probably not what was intended by the user.
for log in existing:
logger = root.manager.loggerDict[log]
if log in child_loggers:
logger.level = logging.NOTSET
logger.handlers = []
logger.propagate = True
elif disable_existing:
logger.disabled = True
# And finally, do the root logger
root = config.get('root', None)
if root:
try:
self.configure_root(root)
except StandardError, e:
raise ValueError('Unable to configure root '
'logger: %s' % e)
finally:
logging._releaseLock()
def configure_formatter(self, config):
"""Configure a formatter from a dictionary."""
if '()' in config:
factory = config['()'] # for use in exception handler
try:
result = self.configure_custom(config)
except TypeError, te:
if "'format'" not in str(te):
raise
#Name of parameter changed from fmt to format.
#Retry with old name.
#This is so that code can be used with older Python versions
#(e.g. by Django)
config['fmt'] = config.pop('format')
config['()'] = factory
result = self.configure_custom(config)
else:
fmt = config.get('format', None)
dfmt = config.get('datefmt', None)
result = logging.Formatter(fmt, dfmt)
return result
def configure_filter(self, config):
"""Configure a filter from a dictionary."""
if '()' in config:
result = self.configure_custom(config)
else:
name = config.get('name', '')
result = logging.Filter(name)
return result
def add_filters(self, filterer, filters):
"""Add filters to a filterer from a list of names."""
for f in filters:
try:
filterer.addFilter(self.config['filters'][f])
except StandardError, e:
raise ValueError('Unable to add filter %r: %s' % (f, e))
def configure_handler(self, config):
"""Configure a handler from a dictionary."""
formatter = config.pop('formatter', None)
if formatter:
try:
formatter = self.config['formatters'][formatter]
except StandardError, e:
raise ValueError('Unable to set formatter '
'%r: %s' % (formatter, e))
level = config.pop('level', None)
filters = config.pop('filters', None)
if '()' in config:
c = config.pop('()')
if not hasattr(c, '__call__') and hasattr(types, 'ClassType') and type(c) != types.ClassType:
c = self.resolve(c)
factory = c
else:
klass = self.resolve(config.pop('class'))
#Special case for handler which refers to another handler
if issubclass(klass, logging.handlers.MemoryHandler) and\
'target' in config:
try:
config['target'] = self.config['handlers'][config['target']]
except StandardError, e:
raise ValueError('Unable to set target handler '
'%r: %s' % (config['target'], e))
factory = klass
kwargs = dict([(k, config[k]) for k in config if valid_ident(k)])
try:
result = factory(**kwargs)
except TypeError, te:
if "'stream'" not in str(te):
raise
#The argument name changed from strm to stream
#Retry with old name.
#This is so that code can be used with older Python versions
#(e.g. by Django)
kwargs['strm'] = kwargs.pop('stream')
result = factory(**kwargs)
if formatter:
result.setFormatter(formatter)
if level is not None:
result.setLevel(logging._checkLevel(level))
if filters:
self.add_filters(result, filters)
return result
def add_handlers(self, logger, handlers):
"""Add handlers to a logger from a list of names."""
for h in handlers:
try:
logger.addHandler(self.config['handlers'][h])
except StandardError, e:
raise ValueError('Unable to add handler %r: %s' % (h, e))
def common_logger_config(self, logger, config, incremental=False):
"""
Perform configuration which is common to root and non-root loggers.
"""
level = config.get('level', None)
if level is not None:
logger.setLevel(logging._checkLevel(level))
if not incremental:
#Remove any existing handlers
for h in logger.handlers[:]:
logger.removeHandler(h)
handlers = config.get('handlers', None)
if handlers:
self.add_handlers(logger, handlers)
filters = config.get('filters', None)
if filters:
self.add_filters(logger, filters)
def configure_logger(self, name, config, incremental=False):
"""Configure a non-root logger from a dictionary."""
logger = logging.getLogger(name)
self.common_logger_config(logger, config, incremental)
propagate = config.get('propagate', None)
if propagate is not None:
logger.propagate = propagate
def configure_root(self, config, incremental=False):
"""Configure a root logger from a dictionary."""
root = logging.getLogger()
self.common_logger_config(root, config, incremental)
dictConfigClass = DictConfigurator
def dictConfig(config):
"""Configure logging using a dictionary."""
dictConfigClass(config).configure()
def listen(port=DEFAULT_LOGGING_CONFIG_PORT):
"""
Start up a socket server on the specified port, and listen for new
configurations.
These will be sent as a file suitable for processing by fileConfig().
Returns a Thread object on which you can call start() to start the server,
and which you can join() when appropriate. To stop the server, call
stopListening().
"""
if not thread:
raise NotImplementedError("listen() needs threading to work")
class ConfigStreamHandler(StreamRequestHandler):
"""
Handler for a logging configuration request.
It expects a completely new logging configuration and uses fileConfig
to install it.
"""
def handle(self):
"""
Handle a request.
Each request is expected to be a 4-byte length, packed using
struct.pack(">L", n), followed by the config file.
Uses fileConfig() to do the grunt work.
"""
import tempfile
try:
conn = self.connection
chunk = conn.recv(4)
if len(chunk) == 4:
slen = struct.unpack(">L", chunk)[0]
chunk = self.connection.recv(slen)
while len(chunk) < slen:
chunk = chunk + conn.recv(slen - len(chunk))
try:
import json
d =json.loads(chunk)
assert isinstance(d, dict)
dictConfig(d)
except:
#Apply new configuration.
file = cStringIO.StringIO(chunk)
try:
fileConfig(file)
except (KeyboardInterrupt, SystemExit):
raise
except:
traceback.print_exc()
except socket.error, e:
if not isinstance(e.args, tuple):
raise
else:
errcode = e.args[0]
if errcode != RESET_ERROR:
raise
class ConfigSocketReceiver(ThreadingTCPServer):
"""
A simple TCP socket-based logging config receiver.
"""
allow_reuse_address = 1
def __init__(self, host='localhost', port=DEFAULT_LOGGING_CONFIG_PORT,
handler=None):
ThreadingTCPServer.__init__(self, (host, port), handler)
logging._acquireLock()
self.abort = 0
logging._releaseLock()
self.timeout = 1
def serve_until_stopped(self):
import select
abort = 0
while not abort:
rd, wr, ex = select.select([self.socket.fileno()],
[], [],
self.timeout)
if rd:
self.handle_request()
logging._acquireLock()
abort = self.abort
logging._releaseLock()
def serve(rcvr, hdlr, port):
server = rcvr(port=port, handler=hdlr)
global _listener
logging._acquireLock()
_listener = server
logging._releaseLock()
server.serve_until_stopped()
return threading.Thread(target=serve,
args=(ConfigSocketReceiver,
ConfigStreamHandler, port))
def stopListening():
"""
Stop the listening server which was created with a call to listen().
"""
global _listener
if _listener:
logging._acquireLock()
_listener.abort = 1
_listener = None
logging._releaseLock()