summaryrefslogtreecommitdiffstats
path: root/Lib/logging/handlers.py
blob: 0801699a5406e104042ca334fe10ed6a6d83c8f1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
# Copyright 2001-2005 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.

Should work under Python versions >= 1.5.2, except that source line
information is not available unless 'sys._getframe()' is.

Copyright (C) 2001-2004 Vinay Sajip. All Rights Reserved.

To use, simply 'import logging' and log away!
"""

import sys, logging, socket, types, os, string, cPickle, struct, time, glob

try:
    import codecs
except ImportError:
    codecs = None

#
# 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

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):
        """
        Use the specified filename for streamed logging
        """
        if codecs is None:
            encoding = None
        logging.FileHandler.__init__(self, filename, mode, encoding)
        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:
            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):
        """
        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)
        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)
        if self.encoding:
            self.stream = codecs.open(self.baseFilename, 'w', self.encoding)
        else:
            self.stream = open(self.baseFilename, 'w')

    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.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):
        BaseRotatingHandler.__init__(self, filename, 'a', encoding)
        self.when = string.upper(when)
        self.backupCount = backupCount
        # 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"
        elif self.when == 'M':
            self.interval = 60 # one minute
            self.suffix = "%Y-%m-%d_%H-%M"
        elif self.when == 'H':
            self.interval = 60 * 60 # one hour
            self.suffix = "%Y-%m-%d_%H"
        elif self.when == 'D' or self.when == 'MIDNIGHT':
            self.interval = 60 * 60 * 24 # one day
            self.suffix = "%Y-%m-%d"
        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"
        else:
            raise ValueError("Invalid rollover interval specified: %s" % self.when)

        self.interval = self.interval * interval # multiply by units requested
        self.rolloverAt = 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
            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 = (24 - currentHour) * 60 * 60 # number of hours in seconds
            r = r + (59 - currentMinute) * 60 # plus the number of minutes (in secs)
            r = r + (59 - currentSecond) # plus the number of seconds
            self.rolloverAt = 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).
            if when.startswith('W'):
                day = t[6] # 0 is Monday
                if day > self.dayOfWeek:
                    daysToWait = (day - self.dayOfWeek) - 1
                    self.rolloverAt = self.rolloverAt + (daysToWait * (60 * 60 * 24))
                if day < self.dayOfWeek:
                    daysToWait = (6 - self.dayOfWeek) + day
                    self.rolloverAt = self.rolloverAt + (daysToWait * (60 * 60 * 24))

        #print "Will rollover at %d, %d seconds from now" % (self.rolloverAt, self.rolloverAt - currentTime)

    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 siguratures 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 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.
        """
        self.stream.close()
        # get the time that this sequence started at and make it a TimeTuple
        t = self.rolloverAt - self.interval
        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])
        #print "%s -> %s" % (self.baseFilename, dfn)
        if self.encoding:
            self.stream = codecs.open(self.baseFilename, 'w', self.encoding)
        else:
            self.stream = open(self.baseFilename, 'w')
        self.rolloverAt = int(time.time()) + self.interval

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):
        """
        A factory method which allows subclasses to define the precise
        type of socket they want.
        """
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        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:
                #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:
            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 <linux/sys/syslog.h>:
    # ======================================================================
    # priorities/facilities are encoded into a single 32-bit quantity, where
    # the bottom 3 bits are the priority (0-7) and the top 28 bits are the
    # facility (0-big number). Both the priorities and the facilities map
    # roughly one-to-one to strings in the syslogd(8) source code.  This
    # mapping is included in this file.
    #
    # priorities (these are ordered)

    LOG_EMERG     = 0       #  system is unusable
    LOG_ALERT     = 1       #  action must be taken immediately
    LOG_CRIT      = 2       #  critical conditions
    LOG_ERR       = 3       #  error conditions
    LOG_WARNING   = 4       #  warning conditions
    LOG_NOTICE    = 5       #  normal but significant condition
    LOG_INFO      = 6       #  informational
    LOG_DEBUG     = 7       #  debug-level messages

    #  facility codes
    LOG_KERN      = 0       #  kernel messages
    LOG_USER      = 1       #  random user-level messages
    LOG_MAIL      = 2       #  mail system
    LOG_DAEMON    = 3       #  system daemons
    LOG_AUTH      = 4       #  security/authorization messages
    LOG_SYSLOG    = 5       #  messages generated internally by syslogd
    LOG_LPR       = 6       #  line printer subsystem
    LOG_NEWS      = 7       #  network news subsystem
    LOG_UUCP      = 8       #  UUCP subsystem
    LOG_CRON      = 9       #  clock daemon
    LOG_AUTHPRIV  = 10  #  security/authorization messages (private)

    #  other codes through 15 reserved for system use
    LOG_LOCAL0    = 16      #  reserved for local use
    LOG_LOCAL1    = 17      #  reserved for local use
    LOG_LOCAL2    = 18      #  reserved for local use
    LOG_LOCAL3    = 19      #  reserved for local use
    LOG_LOCAL4    = 20      #  reserved for local use
    LOG_LOCAL5    = 21      #  reserved for local use
    LOG_LOCAL6    = 22      #  reserved for local use
    LOG_LOCAL7    = 23      #  reserved for local use

    priority_names = {
        "alert":    LOG_ALERT,
        "crit":     LOG_CRIT,
        "critical": LOG_CRIT,
        "debug":    LOG_DEBUG,
        "emerg":    LOG_EMERG,
        "err":      LOG_ERR,
        "error":    LOG_ERR,        #  DEPRECATED
        "info":     LOG_INFO,
        "notice":   LOG_NOTICE,
        "panic":    LOG_EMERG,      #  DEPRECATED
        "warn":     LOG_WARNING,    #  DEPRECATED
        "warning":  LOG_WARNING,
        }

    facility_names = {
        "auth":     LOG_AUTH,
        "authpriv": LOG_AUTHPRIV,
        "cron":     LOG_CRON,
        "daemon":   LOG_DAEMON,
        "kern":     LOG_KERN,
        "lpr":      LOG_LPR,
        "mail":     LOG_MAIL,
        "news":     LOG_NEWS,
        "security": LOG_AUTH,       #  DEPRECATED
        "syslog":   LOG_SYSLOG,
        "user":     LOG_USER,
        "uucp":     LOG_UUCP,
        "local0":   LOG_LOCAL0,
        "local1":   LOG_LOCAL1,
        "local2":   LOG_LOCAL2,
        "local3":   LOG_LOCAL3,
        "local4":   LOG_LOCAL4,
        "local5":   LOG_LOCAL5,
        "local6":   LOG_LOCAL6,
        "local7":   LOG_LOCAL7,
        }

    def __init__(self, address=('localhost', SYSLOG_UDP_PORT), facility=LOG_USER):
        """
        Initialize a handler.

        If address is specified as a string, UNIX socket is used.
        If facility is not specified, LOG_USER is used.
        """
        logging.Handler.__init__(self)

        self.address = address
        self.facility = facility
        if type(address) == types.StringType:
            self._connect_unixsocket(address)
            self.unixsocket = 1
        else:
            self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
            self.unixsocket = 0

        self.formatter = None

    def _connect_unixsocket(self, address):
        self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM)
        # syslog may require either DGRAM or STREAM sockets
        try:
            self.socket.connect(address)
        except socket.error:
            self.socket.close()
            self.socket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
        self.socket.connect(address)

    # curious: when talking to the unix-domain '/dev/log' socket, a
    #   zero-terminator seems to be required.  this string is placed
    #   into a class variable so that it can be overridden if
    #   necessary.
    log_format_string = '<%d>%s\000'

    def encodePriority (self, facility, priority):
        """
        Encode the facility and priority. You can pass in strings or
        integers - if strings are passed, the facility_names and
        priority_names mapping dictionaries are used to convert them to
        integers.
        """
        if type(facility) == types.StringType:
            facility = self.facility_names[facility]
        if type(priority) == types.StringType:
            priority = self.priority_names[priority]
        return (facility << 3) | priority

    def close (self):
        """
        Closes the socket.
        """
        if self.unixsocket:
            self.socket.close()
        logging.Handler.close(self)

    def emit(self, record):
        """
        Emit a record.

        The record is formatted, and then sent to the syslog server. If
        exception information is present, it is NOT sent to the server.
        """
        msg = self.format(record)
        """
        We need to convert record level to lowercase, maybe this will
        change in the future.
        """
        msg = self.log_format_string % (
            self.encodePriority(self.facility,
                                string.lower(record.levelname)),
            msg)
        try:
            if self.unixsocket:
                try:
                    self.socket.send(msg)
                except socket.error:
                    self._connect_unixsocket(self.address)
                    self.socket.send(msg)
            else:
                self.socket.sendto(msg, self.address)
        except:
            self.handleError(record)

class SMTPHandler(logging.Handler):
    """
    A handler class which sends an SMTP email for each logging event.
    """
    def __init__(self, mailhost, fromaddr, toaddrs, subject):
        """
        Initialize the handler.

        Initialize the instance with the from and to addresses and subject
        line of the email. To specify a non-standard SMTP port, use the
        (host, port) tuple format for the mailhost argument.
        """
        logging.Handler.__init__(self)
        if type(mailhost) == types.TupleType:
            host, port = mailhost
            self.mailhost = host
            self.mailport = port
        else:
            self.mailhost = mailhost
            self.mailport = None
        self.fromaddr = fromaddr
        if type(toaddrs) == types.StringType:
            toaddrs = [toaddrs]
        self.toaddrs = toaddrs
        self.subject = subject

    def getSubject(self, record):
        """
        Determine the subject for the email.

        If you want to specify a subject line which is record-dependent,
        override this method.
        """
        return self.subject

    weekdayname = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']

    monthname = [None,
                 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
                 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']

    def date_time(self):
        """
        Return the current date and time formatted for a MIME header.
        Needed for Python 1.5.2 (no email package available)
        """
        year, month, day, hh, mm, ss, wd, y, z = time.gmtime(time.time())
        s = "%s, %02d %3s %4d %02d:%02d:%02d GMT" % (
                self.weekdayname[wd],
                day, self.monthname[month], year,
                hh, mm, ss)
        return s

    def emit(self, record):
        """
        Emit a record.

        Format the record and send it to the specified addressees.
        """
        try:
            import smtplib
            try:
                from email.Utils import formatdate
            except:
                formatdate = self.date_time
            port = self.mailport
            if not port:
                port = smtplib.SMTP_PORT
            smtp = smtplib.SMTP(self.mailhost, port)
            msg = self.format(record)
            msg = "From: %s\r\nTo: %s\r\nSubject: %s\r\nDate: %s\r\n\r\n%s" % (
                            self.fromaddr,
                            string.join(self.toaddrs, ","),
                            self.getSubject(record),
                            formatdate(), msg)
            smtp.sendmail(self.fromaddr, self.toaddrs, msg)
            smtp.quit()
        except:
            self.handleError(record)

class NTEventLogHandler(logging.Handler):
    """
    A handler class which sends events to the NT Event Log. Adds a
    registry entry for the specified application name. If no dllname is
    provided, win32service.pyd (which contains some basic message
    placeholders) is used. Note that use of these placeholders will make
    your event logs big, as the entire message source is held in the log.
    If you want slimmer logs, you have to pass in the name of your own DLL
    which contains the message definitions you want to use in the event log.
    """
    def __init__(self, appname, dllname=None, logtype="Application"):
        logging.Handler.__init__(self)
        try:
            import win32evtlogutil, win32evtlog
            self.appname = appname
            self._welu = win32evtlogutil
            if not dllname:
                dllname = os.path.split(self._welu.__file__)
                dllname = os.path.split(dllname[0])
                dllname = os.path.join(dllname[0], r'win32service.pyd')
            self.dllname = dllname
            self.logtype = logtype
            self._welu.AddSourceToRegistry(appname, dllname, logtype)
            self.deftype = win32evtlog.EVENTLOG_ERROR_TYPE
            self.typemap = {
                logging.DEBUG   : win32evtlog.EVENTLOG_INFORMATION_TYPE,
                logging.INFO    : win32evtlog.EVENTLOG_INFORMATION_TYPE,
                logging.WARNING : win32evtlog.EVENTLOG_WARNING_TYPE,
                logging.ERROR   : win32evtlog.EVENTLOG_ERROR_TYPE,
                logging.CRITICAL: win32evtlog.EVENTLOG_ERROR_TYPE,
         }
        except ImportError:
            print "The Python Win32 extensions for NT (service, event "\
                        "logging) appear not to be available."
            self._welu = None

    def getMessageID(self, record):
        """
        Return the message ID for the event record. If you are using your
        own messages, you could do this by having the msg passed to the
        logger being an ID rather than a formatting string. Then, in here,
        you could use a dictionary lookup to get the message ID. This
        version returns 1, which is the base message ID in win32service.pyd.
        """
        return 1

    def getEventCategory(self, record):
        """
        Return the event category for the record.

        Override this if you want to specify your own categories. This version
        returns 0.
        """
        return 0

    def getEventType(self, record):
        """
        Return the event type for the record.

        Override this if you want to specify your own types. This version does
        a mapping using the handler's typemap attribute, which is set up in
        __init__() to a dictionary which contains mappings for DEBUG, INFO,
        WARNING, ERROR and CRITICAL. If you are using your own levels you will
        either need to override this method or place a suitable dictionary in
        the handler's typemap attribute.
        """
        return self.typemap.get(record.levelno, self.deftype)

    def emit(self, record):
        """
        Emit a record.

        Determine the message ID, event category and event type. Then
        log the message in the NT event log.
        """
        if self._welu:
            try:
                id = self.getMessageID(record)
                cat = self.getEventCategory(record)
                type = self.getEventType(record)
                msg = self.format(record)
                self._welu.ReportEvent(self.appname, id, cat, type, [msg])
            except:
                self.handleError(record)

    def close(self):
        """
        Clean up this handler.

        You can remove the application name from the registry as a
        source of event log entries. However, if you do this, you will
        not be able to see the events as you intended in the Event Log
        Viewer - it needs to be able to access the registry to get the
        DLL name.
        """
        #self._welu.RemoveSourceFromRegistry(self.appname, self.logtype)
        logging.Handler.close(self)

class HTTPHandler(logging.Handler):
    """
    A class which sends records to a Web server, using either GET or
    POST semantics.
    """
    def __init__(self, host, url, method="GET"):
        """
        Initialize the instance with the host, the request URL, and the method
        ("GET" or "POST")
        """
        logging.Handler.__init__(self)
        method = string.upper(method)
        if method not in ["GET", "POST"]:
            raise ValueError, "method must be GET or POST"
        self.host = host
        self.url = url
        self.method = method

    def mapLogRecord(self, record):
        """
        Default implementation of mapping the log record into a dict
        that is sent as the CGI data. Overwrite in your class.
        Contributed by Franz  Glasner.
        """
        return record.__dict__

    def emit(self, record):
        """
        Emit a record.

        Send the record to the Web server as an URL-encoded dictionary
        """
        try:
            import httplib, urllib
            h = httplib.HTTP(self.host)
            url = self.url
            data = urllib.urlencode(self.mapLogRecord(record))
            if self.method == "GET":
                if (string.find(url, '?') >= 0):
                    sep = '&'
                else:
                    sep = '?'
                url = url + "%c%s" % (sep, data)
            h.putrequest(self.method, url)
            if self.method == "POST":
                h.putheader("Content-length", str(len(data)))
            h.endheaders()
            if self.method == "POST":
                h.send(data)
            h.getreply()    #can't do anything with the result
        except:
            self.handleError(record)

class BufferingHandler(logging.Handler):
    """
  A handler class which buffers logging records in memory. Whenever each
  record is added to the buffer, a check is made to see if the buffer should
  be flushed. If it should, then flush() is expected to do what's needed.
    """
    def __init__(self, capacity):
        """
        Initialize the handler with the buffer size.
        """
        logging.Handler.__init__(self)
        self.capacity = capacity
        self.buffer = []

    def shouldFlush(self, record):
        """
        Should the handler flush its buffer?

        Returns true if the buffer is up to capacity. This method can be
        overridden to implement custom flushing strategies.
        """
        return (len(self.buffer) >= self.capacity)

    def emit(self, record):
        """
        Emit a record.

        Append the record. If shouldFlush() tells us to, call flush() to process
        the buffer.
        """
        self.buffer.append(record)
        if self.shouldFlush(record):
            self.flush()

    def flush(self):
        """
        Override to implement custom flushing behaviour.

        This version just zaps the buffer to empty.
        """
        self.buffer = []

    def close(self):
        """
        Close the handler.

        This version just flushes and chains to the parent class' close().
        """
        self.flush()
        logging.Handler.close(self)

class MemoryHandler(BufferingHandler):
    """
    A handler class which buffers logging records in memory, periodically
    flushing them to a target handler. Flushing occurs whenever the buffer
    is full, or when an event of a certain severity or greater is seen.
    """
    def __init__(self, capacity, flushLevel=logging.ERROR, target=None):
        """
        Initialize the handler with the buffer size, the level at which
        flushing should occur and an optional target.

        Note that without a target being set either here or via setTarget(),
        a MemoryHandler is no use to anyone!
        """
        BufferingHandler.__init__(self, capacity)
        self.flushLevel = flushLevel
        self.target = target

    def shouldFlush(self, record):
        """
        Check for buffer full or a record at the flushLevel or higher.
        """
        return (len(self.buffer) >= self.capacity) or \
                (record.levelno >= self.flushLevel)

    def setTarget(self, target):
        """
        Set the target handler for this handler.
        """
        self.target = target

    def flush(self):
        """
        For a MemoryHandler, flushing means just sending the buffered
        records to the target, if there is one. Override if you want
        different behaviour.
        """
        if self.target:
            for record in self.buffer:
                self.target.handle(record)
            self.buffer = []

    def close(self):
        """
        Flush, set the target to None and lose the buffer.
        """
        self.flush()
        self.target = None
        BufferingHandler.close(self)