bin/djbdns-logparse

   1 #!/usr/bin/python3
   2 r"""
   3 Convert tinydns and dnscache logs to human-readable form
   4 """
   5 # Avoid clobbering the top-level exit() built-in.
   6 import sys
   7
   8 from signal import signal, SIGINT
   9 from argparse import ArgumentParser, FileType
  10 from djbdns.io import parse_logfile
  11
  12 # Create an argument parser using the file's docsctring as its
  13 # description.
  14 parser = ArgumentParser(description = __doc__)
  15
  16 # Parse zero or more positional arguments into a list of
  17 # "logfiles". If none are given, read from stdin instead.
  18 parser.add_argument("logfiles",
  19                     metavar="LOGFILE",
  20                     type=FileType("r"),
  21                     nargs="*",
  22                     default=[sys.stdin],
  23                     help="djbdns logfile to process (default: stdin)")
  24
  25 # Warning: argparse automatically opens its file arguments here,
  26 # and they only get closed when the program terminates. There's no
  27 # real benefit to closing them one-at-a-time after calling
  28 # parse_logfile(), because the "scarce" resource of open file
  29 # descriptors gets consumed immediately, before any processing has
  30 # happened. In other words, if you're going to run out of file
  31 # descriptors, it's going to happen right now.
  32 #
  33 # So anyway, don't run this on several million logfiles.
  34 args = parser.parse_args()
  35
  36 # Install a SIGINT handler so thst we don't spit out a stack trace when
  37 # the user accidentally starts the program with no arguments and then
  38 # hits Ctrl-C to kill it.
  39 signal(SIGINT, lambda s,f: sys.exit(0))
  40
  41 for f in args.logfiles:
  42     parse_logfile(f)