Lib/json/tool.py

   1 r"""Command-line tool to validate and pretty-print JSON
   2
   3 Usage::
   4
   5     $ echo '{"json":"obj"}' | python -mjson.tool
   6     {
   7         "json": "obj"
   8     }
   9     $ echo '{ 1.2:3.4}' | python -mjson.tool
  10     Expecting property name: line 1 column 2 (char 2)
  11
  12 """
  13 import sys
  14 import json
  15
  16 def main():
  17     if len(sys.argv) == 1:
  18         infile = sys.stdin
  19         outfile = sys.stdout
  20     elif len(sys.argv) == 2:
  21         infile = open(sys.argv[1], 'rb')
  22         outfile = sys.stdout
  23     elif len(sys.argv) == 3:
  24         infile = open(sys.argv[1], 'rb')
  25         outfile = open(sys.argv[2], 'wb')
  26     else:
  27         raise SystemExit("{0} [infile [outfile]]".format(sys.argv[0]))
  28     try:
  29         obj = json.load(infile)
  30     except ValueError, e:
  31         raise SystemExit(e)
  32     json.dump(obj, outfile, sort_keys=True, indent=4)
  33     outfile.write('\n')
  34
  35
  36 if __name__ == '__main__':
  37     main()