File size: 2,501 Bytes
60f26f9 | 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 42 43 44 45 46 47 48 49 50 51 52 53 | """Verify and extract an individual FlyControl figure archive."""
import argparse, hashlib, json, tarfile
from pathlib import Path
def sha(path):
h=hashlib.sha256()
with Path(path).open('rb') as f:
for block in iter(lambda:f.read(8*1024*1024),b''):h.update(block)
return h.hexdigest()
def extract(figure, root, output):
root,output=Path(root).resolve(),Path(output).resolve()
index=json.loads((root/'archive_index.json').read_text())['archives']
item=next(x for x in index if x['paper_item']==figure)
archive=root/item['path']
assert archive.stat().st_size==item['bytes'] and sha(archive)==item['sha256'], 'Archive integrity failure'
manifest={x['path']:x for x in map(json.loads,(root/'manifests'/f'{figure}.jsonl').open())}
assert len(manifest)==item['members']
output.mkdir(parents=True,exist_ok=True)
seen=set()
with tarfile.open(archive,'r|gz') as tar:
for member in tar:
if not member.isfile() or member.name not in manifest or member.name in seen:
raise ValueError('Unexpected archive member: '+member.name)
dest=(output/member.name).resolve()
if not dest.is_relative_to(output):raise ValueError('Unsafe member path')
expected=manifest[member.name]
assert member.size==expected['bytes']
dest.parent.mkdir(parents=True,exist_ok=True)
if dest.exists():
assert dest.stat().st_size==expected['bytes'] and sha(dest)==expected['sha256'], str(dest)
else:
stream=tar.extractfile(member)
hasher=hashlib.sha256()
try:
with dest.open('xb') as f:
for block in iter(lambda:stream.read(8*1024*1024),b''):
f.write(block);hasher.update(block)
assert hasher.hexdigest()==expected['sha256'], str(dest)
except BaseException:
dest.unlink(missing_ok=True)
raise
seen.add(member.name)
assert seen==set(manifest)
print(json.dumps(dict(figure=figure,members=len(seen),verified=True,output=str(output))))
if __name__=='__main__':
p=argparse.ArgumentParser(description=__doc__)
p.add_argument('--figure',required=True)
p.add_argument('--dataset-dir',default=str(Path(__file__).parent))
p.add_argument('--output',required=True)
a=p.parse_args();extract(a.figure,a.dataset_dir,a.output)
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