bin/djbdns-logparse

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