# Copyright 2001-2007 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.
"""
Additional handlers 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) 2001-2009 Vinay Sajip. All Rights Reserved.
To use, simply 'import logging.handlers' and log away!
"""
import errno, logging, socket, types, os, string, cPickle, struct, time, re
from stat import ST_DEV, ST_INO
try:
import codecs
except ImportError:
codecs = None
try:
unicode
_unicode = True
except NameError:
_unicode = False
#
# Some constants...
#
DEFAULT_TCP_LOGGING_PORT = 9020
DEFAULT_UDP_LOGGING_PORT = 9021
DEFAULT_HTTP_LOGGING_PORT = 9022
DEFAULT_SOAP_LOGGING_PORT = 9023
SYSLOG_UDP_PORT = 514
_MIDNIGHT = 24 * 60 * 60 # number of seconds in a day
class BaseRotatingHandler(logging.FileHandler):
"""
Base class for handlers that rotate log files at a certain point.
Not meant to be instantiated directly. Instead, use RotatingFileHandler
or TimedRotatingFileHandler.
"""
def __init__(self, filename, mode, encoding=None, delay=0):
"""
Use the specified filename for streamed logging
"""
if codecs is None:
encoding = None
logging.FileHandler.__init__(self, filename, mode, encoding, delay)
self.mode = mode
self.encoding = encoding
def emit(self, record):
"""
Emit a record.
Output the record to the file, catering for rollover as described
in doRollover().
"""
try:
if self.shouldRollover(record):
self.doRollover()
logging.FileHandler.emit(self, record)
except (KeyboardInterrupt, SystemExit):
raise
except:
self.handleError(record)
class RotatingFileHandler(BaseRotatingHandler):
"""
Handler for logging to a set of files, which switches from one file
to the next when the current file reaches a certain size.
"""
def __init__(self, filename, mode='a', maxBytes=0, backupCount=0, encoding=None, delay=0):
"""
Open the specified file and use it as the stream for logging.
By default, the file grows indefinitely. You can specify particular
values of maxBytes and backupCount to allow the file to rollover at
a predetermined size.
Rollover occurs whenever the current log file is nearly maxBytes in
length. If backupCount is >= 1, the system will successively create
new files with the same pathname as the base file, but with extensions
".1", ".2" etc. appended to it. For example, with a backupCount of 5
and a base file name of "app.log", you would get "app.log",
"app.log.1", "app.log.2", ... through to "app.log.5". The file being
written to is always "app.log" - when it gets filled up, it is closed
and renamed to "app.log.1", and if files "app.log.1", "app.log.2" etc.
exist, then they are renamed to "app.log.2", "app.log.3" etc.
respectively.
If maxBytes is zero, rollover never occurs.
"""
if maxBytes > 0:
mode = 'a' # doesn't make sense otherwise!
BaseRotatingHandler.__init__(self, filename, mode, encoding, delay)
self.maxBytes = maxBytes
self.backupCount = backupCount
def doRollover(self):
"""
Do a rollover, as described in __init__().
"""
self.stream.close()
if self.backupCount > 0:
for i in range(self.backupCount - 1, 0, -1):
sfn = "%s.%d" % (self.baseFilename, i)
dfn = "%s.%d" % (self.baseFilename, i + 1)
if os.path.exists(sfn):
#print "%s -> %s" % (sfn, dfn)
if os.path.exists(dfn):
os.remove(dfn)
os.rename(sfn, dfn)
dfn = self.baseFilename + ".1"
if os.path.exists(dfn):
os.remove(dfn)
os.rename(self.baseFilename, dfn)
#print "%s -> %s" % (self.baseFilename, dfn)
self.mode = 'w'
self.stream = self._open()
def shouldRollover(self, record):
"""
Determine if rollover should occur.
Basically, see if the supplied record would cause the file to exceed
the size limit we have.
"""
if self.stream is None: # delay was set...
self.stream = self._open()
if self.maxBytes > 0: # are we rolling over?
msg = "%s\n" % self.format(record)
self.stream.seek(0, 2) #due to non-posix-compliant Windows feature
if self.stream.tell() + len(msg) >= self.maxBytes:
return 1
return 0
class TimedRotatingFileHandler(BaseRotatingHandler):
"""
Handler for logging to a file, rotating the log file at certain timed
intervals.
If backupCount is > 0, when rollover is done, no more than backupCount
files are kept - the oldest ones are deleted.
"""
def __init__(self, filename, when='h', interval=1, backupCount=0, encoding=None, delay=0, utc=0):
BaseRotatingHandler.__init__(self, filename, 'a', encoding, delay)
self.when = string.upper(when)
self.backupCount = backupCount
self.utc = utc
# Calculate the real rollover interval, which is just the number of
# seconds between rollovers. Also set the filename suffix used when
# a rollover occurs. Current 'when' events supported:
# S - Seconds
# M - Minutes
# H - Hours
# D - Days
# midnight - roll over at midnight
# W{0-6} - roll over on a certain day; 0 - Monday
#
# Case of the 'when' specifier is not important; lower or upper case
# will work.
currentTime = int(time.time())
if self.when == 'S':
self.interval = 1 # one second
self.suffix = "%Y-%m-%d_%H-%M-%S"
self.extMatch = r"^\d{4}-\d{2}-\d{2}_\d{2}-\d{2}-\d{2}$"
elif self.when == 'M':
self.interval = 60 # one minute
self.suffix = "%Y-%m-%d_%H-%M"
self.extMatch = r"^\d{4}-\d{2}-\d{2}_\d{2}-\d{2}$"
elif self.when == 'H':
self.interval = 60 * 60 # one hour
self.suffix = "%Y-%m-%d_%H"
self.extMatch = r"^\d{4}-\d{2}-\d{2}_\d{2}$"
elif self.when == 'D' or self.when == 'MIDNIGHT':
self.interval = 60 * 60 * 24 # one day
self.suffix = "%Y-%m-%d"
self.extMatch = r"^\d{4}-\d{2}-\d{2}$"
elif self.when.startswith('W'):
self.interval = 60 * 60 * 24 * 7 # one week
if len(self.when) != 2:
raise ValueError("You must specify a day for weekly rollover from 0 to 6 (0 is Monday): %s" % self.when)
if self.when[1] < '0' or self.when[1] > '6':
raise ValueError("Invalid day specified for weekly rollover: %s" % self.when)
self.dayOfWeek = int(self.when[1])
self.suffix = "%Y-%m-%d"
self.extMatch = r"^\d{4}-\d{2}-\d{2}$"
else:
raise ValueError("Invalid rollover interval specified: %s" % self.when)
self.extMatch = re.compile(self.extMatch)
self.interval = self.interval * interval # multiply by units requested
self.rolloverAt = self.computeRollover(int(time.time()))
#print "Will rollover at %d, %d seconds from now" % (self.rolloverAt, self.rolloverAt - currentTime)
def computeRollover(self, currentTime):
"""
Work out the rollover time based on the specified time.
"""
result = currentTime + self.interval
# If we are rolling over at midnight or weekly, then the interval is already known.
# What we need to figure out is WHEN the next interval is. In other words,
# if you are rolling over at midnight, then your base interval is 1 day,
# but you want to start that one day clock at midnight, not now. So, we
# have to fudge the rolloverAt value in order to trigger the first rollover
# at the right time. After that, the regular interval will take care of
# the rest. Note that this code doesn't care about leap seconds. :)
if self.when == 'MIDNIGHT' or self.when.startswith('W'):
# This could be done with less code, but I wanted it to be clear
if self.utc:
t = time.gmtime(currentTime)
else:
t = time.localtime(currentTime)
currentHour = t[3]
currentMinute = t[4]
currentSecond = t[5]
# r is the number of seconds left between now and midnight
r = _MIDNIGHT - ((currentHour * 60 + currentMinute) * 60 +
currentSecond)
result = currentTime + r
# If we are rolling over on a certain day, add in the number of days until
# the next rollover, but offset by 1 since we just calculated the time
# until the next day starts. There are three cases:
# Case 1) The day to rollover is today; in this case, do nothing
# Case 2) The day to rollover is further in the interval (i.e., today is
# day 2 (Wednesday) and rollover is on day 6 (Sunday). Days to
# next rollover is simply 6 - 2 - 1, or 3.
# Case 3) The day to rollover is behind us in the interval (i.e., today
# is day 5 (Saturday) and rollover is on day 3 (Thursday).
# Days to rollover is 6 - 5 + 3, or 4. In this case, it's the
# number of days left in the current week (1) plus the number
# of days in the next week until the rollover day (3).
# The calculations described in 2) and 3) above need to have a day added.
# This is because the above time calculation takes us to midnight on this
# day, i.e. the start of the next day.
if self.when.startswith('W'):
day = t[6] # 0 is Monday
if day != self.dayOfWeek:
if day < self.dayOfWeek:
daysToWait = self.dayOfWeek - day
else:
daysToWait = 6 - day + self.dayOfWeek + 1
newRolloverAt = result + (daysToWait * (60 * 60 * 24))
if not self.utc:
dstNow = t[-1]
dstAtRollover = time.localtime(newRolloverAt)[-1]
if dstNow != dstAtRollover:
if not dstNow: # DST kicks in before next rollover, so we need to deduct an hour
newRolloverAt = newRolloverAt - 3600
else: # DST bows out before next rollover, so we need to add an hour
newRolloverAt = newRolloverAt + 3600
result = newRolloverAt
return result
def shouldRollover(self, record):
"""
Determine if rollover should occur.
record is not used, as we are just comparing times, but it is needed so
the method signatures are the same
"""
t = int(time.time())
if t >= self.rolloverAt:
return 1
#print "No need to rollover: %d, %d" % (t, self.rolloverAt)
return 0
def getFilesToDelete(self):
"""
Determine the files to delete when rolling over.
More specific than the earlier method, which just used glob.glob().
"""
dirName, baseName = os.path.split(self.baseFilename)
fileNames = os.listdir(dirName)
result = []
prefix = baseName + "."
plen = len(prefix)
for fileName in fileNames:
if fileName[:plen] == prefix:
suffix = fileName[plen:]
if self.extMatch.match(suffix):
result.append(os.path.join(dirName, fileName))
result.sort()
if len(result) < self.backupCount:
result = []
else:
result = result[:len(result) - self.backupCount]
return result
def doRollover(self):
"""
do a rollover; in this case, a date/time stamp is appended to the filename
when the rollover happens. However, you want the file to be named for the
start of the interval, not the current time. If there is a backup count,
then we have to get a list of matching filenames, sort them and remove
the one with the oldest suffix.
"""
if self.stream:
self.stream.close()
# get the time that this sequence started at and make it a TimeTuple
t = self.rolloverAt - self.interval
if self.utc:
timeTuple = time.gmtime(t)
else:
timeTuple = time.localtime(t)
dfn = self.baseFilename + "." + time.strftime(self.suffix, timeTuple)
if os.path.exists(dfn):
os.remove(dfn)
os.rename(self.baseFilename, dfn)
if self.backupCount > 0:
# find the oldest log file and delete it
#s = glob.glob(self.baseFilename + ".20*")
#if len(s) > self.backupCount:
# s.sort()
# os.remove(s[0])
for s in self.getFilesToDelete():
os.remove(s)
#print "%s -> %s" % (self.baseFilename, dfn)
self.mode = 'w'
self.stream = self._open()
currentTime = int(time.time())
newRolloverAt = self.computeRollover(currentTime)
while newRolloverAt <= currentTime:
newRolloverAt = newRolloverAt + self.interval
#If DST changes and midnight or weekly rollover, adjust for this.
if (self.when == 'MIDNIGHT' or self.when.startswith('W')) and not self.utc:
dstNow = time.localtime(currentTime)[-1]
dstAtRollover = time.localtime(newRolloverAt)[-1]
if dstNow != dstAtRollover:
if not dstNow: # DST kicks in before next rollover, so we need to deduct an hour
newRolloverAt = newRolloverAt - 3600
else: # DST bows out before next rollover, so we need to add an hour
newRolloverAt = newRolloverAt + 3600
self.rolloverAt = newRolloverAt
class WatchedFileHandler(logging.FileHandler):
"""
A handler for logging to a file, which watches the file
to see if it has changed while in use. This can happen because of
usage of programs such as newsyslog and logrotate which perform
log file rotation. This handler, intended for use under Unix,
watches the file to see if it has changed since the last emit.
(A file has changed if its device or inode have changed.)
If it has changed, the old file stream is closed, and the file
opened to get a new stream.
This handler is not appropriate for use under Windows, because
under Windows open files cannot be moved or renamed - logging
opens the files with exclusive locks - and so there is no need
for such a handler. Furthermore, ST_INO is not supported under
Windows; stat always returns zero for this value.
This handler is based on a suggestion and patch by Chad J.
Schroeder.
"""
def __init__(self, filename, mode='a', encoding=None, delay=0):
logging.FileHandler.__init__(self, filename, mode, encoding, delay)
self.dev, self.ino = -1, -1
self._statstream()
def _statstream(self):
if self.stream:
sres = os.fstat(self.stream.fileno())
self.dev, self.ino = sres[ST_DEV], sres[ST_INO]
def emit(self, record):
"""
Emit a record.
First check if the underlying file has changed, and if it
has, close the old stream and reopen the file to get the
current stream.
"""
try:
# stat the file by path, checking for existence
sres = os.stat(self.baseFilename)
except OSError as err:
if err.errno == errno.ENOENT:
sres = None
else:
raise
# compare file system stat with that of our stream file handle
if not sres or sres[ST_DEV] != self.dev or sres[ST_INO] != self.ino:
if self.stream is not None:
# we have an open file handle, clean it up
self.stream.flush()
self.stream.close()
# open new file handle and get new stat info from that fd
self.stream = self._open()
self._statstream()
logging.FileHandler.emit(self, record)
class SocketHandler(logging.Handler):
"""
A handler class which writes logging records, in pickle format, to
a streaming socket. The socket is kept open across logging calls.
If the peer resets it, an attempt is made to reconnect on the next call.
The pickle which is sent is that of the LogRecord's attribute dictionary
(__dict__), so that the receiver does not need to have the logging module
installed in order to process the logging event.
To unpickle the record at the receiving end into a LogRecord, use the
makeLogRecord function.
"""
def __init__(self, host, port):
"""
Initializes the handler with a specific host address and port.
The attribute 'closeOnError' is set to 1 - which means that if
a socket error occurs, the socket is silently closed and then
reopened on the next logging call.
"""
logging.Handler.__init__(self)
self.host = host
self.port = port
self.sock = None
self.closeOnError = 0
self.retryTime = None
#
# Exponential backoff parameters.
#
self.retryStart = 1.0
self.retryMax = 30.0
self.retryFactor = 2.0
def makeSocket(self, timeout=1):
"""
A factory method which allows subclasses to define the precise
type of socket they want.
"""
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
if hasattr(s, 'settimeout'):
s.settimeout(timeout)
s.connect((self.host, self.port))
return s
def createSocket(self):
"""
Try to create a socket, using an exponential backoff with
a max retry time. Thanks to Robert Olson for the original patch
(SF #815911) which has been slightly refactored.
"""
now = time.time()
# Either retryTime is None, in which case this
# is the first time back after a disconnect, or
# we've waited long enough.
if self.retryTime is None:
attempt = 1
else:
attempt = (now >= self.retryTime)
if attempt:
try:
self.sock = self.makeSocket()
self.retryTime = None # next time, no delay before trying
except socket.error:
#Creation failed, so set the retry time and return.
if self.retryTime is None:
self.retryPeriod = self.retryStart
else:
self.retryPeriod = self.retryPeriod * self.retryFactor
if self.retryPeriod > self.retryMax:
self.retryPeriod = self.retryMax
self.retryTime = now + self.retryPeriod
def send(self, s):
"""
Send a pickled string to the socket.
This function allows for partial sends which can happen when the
network is busy.
"""
if self.sock is None:
self.createSocket()
#self.sock can be None either because we haven't reached the retry
#time yet, or because we have reached the retry time and retried,
#but are still unable to connect.
if self.sock:
try:
if hasattr(self.sock, "sendall"):
self.sock.sendall(s)
else:
sentsofar = 0
left = len(s)
while left > 0:
sent = self.sock.send(s[sentsofar:])
sentsofar = sentsofar + sent
left = left - sent
except socket.error:
self.sock.close()
self.sock = None # so we can call createSocket next time
def makePickle(self, record):
"""
Pickles the record in binary format with a length prefix, and
returns it ready for transmission across the socket.
"""
ei = record.exc_info
if ei:
dummy = self.format(record) # just to get traceback text into record.exc_text
record.exc_info = None # to avoid Unpickleable error
s = cPickle.dumps(record.__dict__, 1)
if ei:
record.exc_info = ei # for next handler
slen = struct.pack(">L", len(s))
return slen + s
def handleError(self, record):
"""
Handle an error during logging.
An error has occurred during logging. Most likely cause -
connection lost. Close the socket so that we can retry on the
next event.
"""
if self.closeOnError and self.sock:
self.sock.close()
self.sock = None #try to reconnect next time
else:
logging.Handler.handleError(self, record)
def emit(self, record):
"""
Emit a record.
Pickles the record and writes it to the socket in binary format.
If there is an error with the socket, silently drop the packet.
If there was a problem with the socket, re-establishes the
socket.
"""
try:
s = self.makePickle(record)
self.send(s)
except (KeyboardInterrupt, SystemExit):
raise
except:
self.handleError(record)
def close(self):
"""
Closes the socket.
"""
if self.sock:
self.sock.close()
self.sock = None
logging.Handler.close(self)
class DatagramHandler(SocketHandler):
"""
A handler class which writes logging records, in pickle format, to
a datagram socket. The pickle which is sent is that of the LogRecord's
attribute dictionary (__dict__), so that the receiver does not need to
have the logging module installed in order to process the logging event.
To unpickle the record at the receiving end into a LogRecord, use the
makeLogRecord function.
"""
def __init__(self, host, port):
"""
Initializes the handler with a specific host address and port.
"""
SocketHandler.__init__(self, host, port)
self.closeOnError = 0
def makeSocket(self):
"""
The factory method of SocketHandler is here overridden to create
a UDP socket (SOCK_DGRAM).
"""
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
return s
def send(self, s):
"""
Send a pickled string to a socket.
This function no longer allows for partial sends which can happen
when the network is busy - UDP does not guarantee delivery and
can deliver packets out of sequence.
"""
if self.sock is None:
self.createSocket()
self.sock.sendto(s, (self.host, self.port))
class SysLogHandler(logging.Handler):
"""
A handler class which sends formatted logging records to a syslog
server. Based on Sam Rushing's syslog module:
http://www.nightmare.com/squirl/python-ext/misc/syslog.py
Contributed by Nicolas Untz (after which minor refactoring changes
have been made).
"""
# from