| r"""Command-line tool to validate and pretty-print JSON | |
| Usage:: | |
| $ echo '{"json":"obj"}' | python -m json.tool | |
| { | |
| "json": "obj" | |
| } | |
| $ echo '{ 1.2:3.4}' | python -m json.tool | |
| Expecting property name enclosed in double quotes: line 1 column 3 (char 2) | |
| """ | |
| import argparse | |
| import json | |
| import sys | |
| from pathlib import Path | |
| def main(): | |
| prog = 'python -m json.tool' | |
| description = ('A simple command line interface for json module ' | |
| 'to validate and pretty-print JSON objects.') | |
| parser = argparse.ArgumentParser(prog=prog, description=description) | |
| parser.add_argument('infile', nargs='?', | |
| type=argparse.FileType(encoding="utf-8"), | |
| help='a JSON file to be validated or pretty-printed', | |
| default=sys.stdin) | |
| parser.add_argument('outfile', nargs='?', | |
| type=Path, | |
| help='write the output of infile to outfile', | |
| default=None) | |
| parser.add_argument('--sort-keys', action='store_true', default=False, | |
| help='sort the output of dictionaries alphabetically by key') | |
| parser.add_argument('--no-ensure-ascii', dest='ensure_ascii', action='store_false', | |
| help='disable escaping of non-ASCII characters') | |
| parser.add_argument('--json-lines', action='store_true', default=False, | |
| help='parse input using the JSON Lines format. ' | |
| 'Use with --no-indent or --compact to produce valid JSON Lines output.') | |
| group = parser.add_mutually_exclusive_group() | |
| group.add_argument('--indent', default=4, type=int, | |
| help='separate items with newlines and use this number ' | |
| 'of spaces for indentation') | |
| group.add_argument('--tab', action='store_const', dest='indent', | |
| const='\t', help='separate items with newlines and use ' | |
| 'tabs for indentation') | |
| group.add_argument('--no-indent', action='store_const', dest='indent', | |
| const=None, | |
| help='separate items with spaces rather than newlines') | |
| group.add_argument('--compact', action='store_true', | |
| help='suppress all whitespace separation (most compact)') | |
| options = parser.parse_args() | |
| dump_args = { | |
| 'sort_keys': options.sort_keys, | |
| 'indent': options.indent, | |
| 'ensure_ascii': options.ensure_ascii, | |
| } | |
| if options.compact: | |
| dump_args['indent'] = None | |
| dump_args['separators'] = ',', ':' | |
| with options.infile as infile: | |
| try: | |
| if options.json_lines: | |
| objs = (json.loads(line) for line in infile) | |
| else: | |
| objs = (json.load(infile),) | |
| if options.outfile is None: | |
| out = sys.stdout | |
| else: | |
| out = options.outfile.open('w', encoding='utf-8') | |
| with out as outfile: | |
| for obj in objs: | |
| json.dump(obj, outfile, **dump_args) | |
| outfile.write('\n') | |
| except ValueError as e: | |
| raise SystemExit(e) | |
| if __name__ == '__main__': | |
| try: | |
| main() | |
| except BrokenPipeError as exc: | |
| sys.exit(exc.errno) | |