sort_json.py

#!/usr/bin/env python3
from argparse import ArgumentParser
import json
from pathlib import Path
from typing import Optional, Sequence


def main(argv: Optional[Sequence[str]] = None) -> int:
    parser = ArgumentParser()
    parser.add_argument(
        "--sort-keys", type=lambda v: v.split(","), default=[], help="Keys to sort"
    )
    parser.add_argument("filenames", nargs="*", type=Path, help="Filenames to fix")
    args = parser.parse_args(argv)

    def object_pairs_hook(pairs):
        return {
            name: sorted(set(value), key=str.lower) if name in args.sort_keys else value
            for name, value in pairs
        }

    status = 0
    for path in args.filenames:
        original = path.read_text()
        try:
            content = json.loads(original, object_pairs_hook=object_pairs_hook)
        except ValueError:
            status = 2  # invalid json format
        else:
            pretty = f"{json.dumps(content, indent=2)}\n"  # include trailing newline
            path.write_text(pretty)
            status = (
                status or original != pretty
            )  # record whether modifications were made
    return status


if __name__ == "__main__":
    raise SystemExit(main())