1r"""Command-line tool to validate and pretty-print JSON 2 3Usage:: 4 5 $ echo '{"json":"obj"}' | python -m json.tool 6 { 7 "json": "obj" 8 } 9 $ echo '{ 1.2:3.4}' | python -m json.tool 10 Expecting property name enclosed in double quotes: line 1 column 3 (char 2) 11 12""" 13import argparse 14import json 15import sys 16 17 18def main(): 19 prog = 'python -m json.tool' 20 description = ('A simple command line interface for json module ' 21 'to validate and pretty-print JSON objects.') 22 parser = argparse.ArgumentParser(prog=prog, description=description) 23 parser.add_argument('infile', nargs='?', 24 type=argparse.FileType(encoding="utf-8"), 25 help='a JSON file to be validated or pretty-printed', 26 default=sys.stdin) 27 parser.add_argument('outfile', nargs='?', 28 type=argparse.FileType('w', encoding="utf-8"), 29 help='write the output of infile to outfile', 30 default=sys.stdout) 31 parser.add_argument('--sort-keys', action='store_true', default=False, 32 help='sort the output of dictionaries alphabetically by key') 33 parser.add_argument('--json-lines', action='store_true', default=False, 34 help='parse input using the jsonlines format') 35 options = parser.parse_args() 36 37 infile = options.infile 38 outfile = options.outfile 39 sort_keys = options.sort_keys 40 json_lines = options.json_lines 41 with infile, outfile: 42 try: 43 if json_lines: 44 objs = (json.loads(line) for line in infile) 45 else: 46 objs = (json.load(infile), ) 47 for obj in objs: 48 json.dump(obj, outfile, sort_keys=sort_keys, indent=4) 49 outfile.write('\n') 50 except ValueError as e: 51 raise SystemExit(e) 52 53 54if __name__ == '__main__': 55 main() 56