bin/djbdns-logparse: use argparse for arg parse.

diff --git a/bin/djbdns-logparse b/bin/djbdns-logparse
index 6cb702fc084ede27fd4271dc4226f0469fa5ea1b..32c7ba106139916df2cd0241c2e50956e824e815 100755 (executable)
--- a/bin/djbdns-logparse
+++ b/bin/djbdns-logparse
@@ -1,4 +1,8 @@
 #!/usr/bin/python3
+"""
+Convert tinydns and dnscache logs to human-readable form
+"""
+
 #
 # Reads log files from tinydns and/or dnscache and prints them out in
 # human-readable form. Logs can be supplied on stdin, or listed on the
@@ -25,6 +29,7 @@ from struct import pack
 from time import strftime, gmtime
 from subprocess import Popen, PIPE
 
+
 # common components of line-matching regexes
 timestamp_pat = r'[\d-]+ [\d:\.]+'      # output of tai64nlocal
 hex4_pat = r'[0-9a-f]{4}'
@@ -206,7 +211,7 @@ def handle_tinydns_log(line, match):
                % (code, ip, port, id, type, name))
 
 
-def parse_logfile(file, filename):
+def parse_logfile(file):
     # Open pipe to tai64nlocal: we will write lines of our input (the
     # raw log file) to it, and read log lines with readable timestamps
     # from it.
@@ -229,15 +234,24 @@ def parse_logfile(file, filename):
         sys.stdout.write(line)
 
 def main():
-    if len(sys.argv) > 1:
-        for filename in sys.argv[1:]:
-            if filename == "-":
-                parse_logfile(sys.stdin, "(stdin)")
-            else:
-                with open(filename) as file:
-                    parse_logfile(file, filename)
-    else:
-        parse_logfile(sys.stdin, "(stdin)")
+    # Create an argument parser using the file's docsctring as its
+    # description.
+    from argparse import ArgumentParser, FileType
+    parser = ArgumentParser(description = __doc__)
+
+    # Parse zero or more positional arguments into a list of
+    # "logfiles". If none are given, read from stdin instead.
+    parser.add_argument("logfiles",
+                        metavar="LOGFILE",
+                        type=FileType("r"),
+                        nargs="*",
+                        default=[sys.stdin],
+                        help="djbdns logfile to process (default: stdin)")
+
+    args = parser.parse_args()
+    for f in args.logfiles:
+        parse_logfile(f)
+