File size: 1,732 Bytes
ca3d57d | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 | #!/usr/bin/env python3
"""Restore text Parquet assets to their original relative paths, checking hashes."""
import argparse
import hashlib
from pathlib import Path, PurePosixPath
import pyarrow.parquet as pq
def main():
p = argparse.ArgumentParser()
p.add_argument("--dataset-root", type=Path, required=True)
p.add_argument("--output", type=Path, required=True)
args = p.parse_args()
count = 0
for base in ["level1/text", "level1/audio"]:
for parquet in sorted((args.dataset_root / base).rglob("*.parquet")):
for batch in pq.ParquetFile(parquet).iter_batches(batch_size=4096):
for row in batch.to_pylist():
rel = PurePosixPath(row["original_relpath"])
if rel.is_absolute() or ".." in rel.parts:
raise ValueError("Unsafe relative path")
raw = row["text"].encode("utf-8")
assert hashlib.sha256(raw).hexdigest() == row["sha256"]
out = args.output / str(rel)
# Refuse writing outside the requested output tree through symlinks.
if not out.resolve().is_relative_to(args.output.resolve()):
raise ValueError("Output path escapes root")
out.parent.mkdir(parents=True, exist_ok=True)
if out.exists():
if out.read_bytes() != raw:
raise FileExistsError(out)
else:
with out.open("xb") as f:
f.write(raw)
count += 1
print(f"Restored and verified {count} text files")
if __name__ == "__main__":
main()
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