| """Verify the downloaded bundle, then restore images and original JSONL files.""" |
| import argparse |
| import hashlib |
| import json |
| import os |
| from pathlib import Path, PurePosixPath |
| import shutil |
| import tarfile |
|
|
|
|
| def main(): |
| parser = argparse.ArgumentParser(description=__doc__) |
| parser.add_argument('--bundle', type=Path, default=Path(__file__).resolve().parent) |
| parser.add_argument('--destination', type=Path) |
| parser.add_argument('--verify-only', action='store_true') |
| args = parser.parse_args() |
| root = args.bundle.resolve() |
| if not args.verify_only and args.destination is None: |
| parser.error('--destination is required for extraction') |
| for line in (root / 'SHA256SUMS').read_text().splitlines(): |
| expected, rel = line.split(' ', 1) |
| p = PurePosixPath(rel) |
| assert not p.is_absolute() and '..' not in p.parts |
| h = hashlib.sha256() |
| with (root / rel).open('rb') as file: |
| for block in iter(lambda: file.read(8 * 1024 * 1024), b''): |
| h.update(block) |
| if h.hexdigest() != expected: |
| raise RuntimeError(f'SHA-256 mismatch: {rel}') |
| print(f'Verified {rel}', flush=True) |
| if args.verify_only: |
| return |
| dest = args.destination.resolve() |
| dest.mkdir(parents=True, exist_ok=True) |
| for name in ('images', 'annotations'): |
| if (dest / name).exists(): |
| raise RuntimeError(f'Refusing to overwrite {dest / name}; select an empty destination') |
| expected_images = json.loads((root / 'manifests/package_summary.json').read_text())['image_count'] |
| count = 0 |
| for shard in json.loads((root / 'manifests/shards.json').read_text())['shards']: |
| shard_count = 0 |
| with tarfile.open(root / shard['path'], mode='r|') as archive: |
| for member in archive: |
| p = PurePosixPath(member.name) |
| if not member.isfile() or p.is_absolute() or '..' in p.parts or p.parts[0] != 'images': |
| raise RuntimeError(f'Unsafe archive member: {member.name}') |
| target = dest / member.name |
| target.parent.mkdir(parents=True, exist_ok=True) |
| with archive.extractfile(member) as source, target.open('xb') as out: |
| shutil.copyfileobj(source, out) |
| if target.stat().st_size != member.size: |
| raise RuntimeError(f'Incomplete image: {target}') |
| shard_count += 1 |
| if shard_count != shard['image_count']: |
| raise RuntimeError(f'Image count mismatch: {shard["path"]}') |
| count += shard_count |
| print(f'Extracted {shard["path"]}: {count:,} images', flush=True) |
| if count != expected_images: |
| raise RuntimeError('Total image count mismatch') |
| shutil.copytree(root / 'annotations', dest / 'annotations') |
| shutil.copyfile(root / 'source_roots.yaml', dest / 'source_roots.yaml') |
| print(f'Complete: {count:,} images and three annotation files in {dest}', flush=True) |
|
|
|
|
| if __name__ == '__main__': |
| main() |
|
|
