Script for getting objects out of the Minecraft launcher database, like sounds

get_objects.py

#!/usr/bin/env python3

import fnmatch
import json
import shutil

from pathlib import Path

def indexes(assets_dir):
    return [
        p.stem for p in Path(assets_dir, "indexes").glob("*.json")
    ]

def object_hashes(index_path, object_pattern):
    with Path(index_path).open("r") as f:
        index = json.load(f)

    return {
        object_path: description["hash"]

        for object_path, description in index["objects"].items()

        if fnmatch.fnmatch(object_path, object_pattern)
    }

def object_paths(index_path, object_pattern):
    index_path = Path(index_path)

    return {
        object_path: Path(index_path.parent.parent, "objects", hash[:2], hash)

        for object_path, hash in
        object_hashes(index_path, object_pattern).items()
    }

def main(args):
    if args.list_indexes:
        for index in indexes(args.assets_dir):
            print(index)

    else:
        index_path = Path(args.assets_dir, "indexes", args.index + ".json")

        objects = object_paths(index_path, args.pattern)
        if len(objects) <= 0:
            print("Unable to find any objects!")

            return

        args.output_dir.mkdir(parents=True, exist_ok=True)

        for object_path, file_path in objects.items():
            result_path = args.output_dir / object_path.replace("/", "_")

            shutil.copyfile(file_path, result_path)

if __name__ == "__main__":
    import sys
    import argparse

    parser = argparse.ArgumentParser()

    parser.add_argument("--assets-dir", type=Path, help="The base assets directory", default=Path())

    parser.add_argument("-l", "--list-indexes", help="List the possible indexes", action="store_true")

    # NOTE: I don't enjoy this.
    listing_indexes = (
        "--list-indexes" in sys.argv[1:] or
        "-l"             in sys.argv[1:]
    )

    parser.add_argument("-o", "--output-dir", type=Path, help="The directory to place the objects", default=Path())

    parser.add_argument("-i", "--index", help="The index for the objects", required=not listing_indexes)

    parser.add_argument("-p", "--pattern", help="The pattern for object paths to extract", required=not listing_indexes)

    main(parser.parse_args())