| """Verify and reconstruct content-addressed MemRSI experimental artifacts (stdlib only).""" |
| import argparse,gzip,hashlib,json,tarfile |
| from pathlib import Path,PurePosixPath |
|
|
| def digest(path): |
| h=hashlib.sha256() |
| with path.open('rb') as f: |
| for chunk in iter(lambda:f.read(4*1024*1024),b''):h.update(chunk) |
| return h.hexdigest() |
|
|
| def main(): |
| p=argparse.ArgumentParser(description=__doc__);p.add_argument('--data-dir',type=Path,required=True);p.add_argument('--output',type=Path,required=True);p.add_argument('--text-only',action='store_true');a=p.parse_args() |
| checks=json.loads((a.data_dir/'DATA-SHA256.json').read_text());need={'file-index.jsonl.gz','text-objects.tar.gz'} |
| if not a.text_only:need.add('media-objects.tar.gz') |
| for n in need: |
| assert digest(a.data_dir/n)==checks[n]['sha256'],f'Archive checksum mismatch: {n}' |
| with gzip.open(a.data_dir/'file-index.jsonl.gz','rt') as f:rows=[json.loads(l) for l in f] |
| by_archive={} |
| for r in rows: |
| if a.text_only and r['disposition']!='text':continue |
| by_archive.setdefault(r['archive'],{}).setdefault(r['object'],[]).append(r) |
| a.output.mkdir(parents=True,exist_ok=True);base=a.output.resolve();count=0 |
| for n,objects in by_archive.items(): |
| with tarfile.open(a.data_dir/n,'r|gz') as archive: |
| for member in archive: |
| if member.name not in objects:continue |
| assert member.isfile(),'Unexpected non-file archive object' |
| data=archive.extractfile(member).read();sha=hashlib.sha256(data).hexdigest() |
| for r in objects.pop(member.name): |
| assert sha==r['public_sha256'] and len(data)==r['public_bytes'],r['path'] |
| rel=PurePosixPath(r['path']);assert not rel.is_absolute() and '..' not in rel.parts |
| dest=base/str(rel);assert dest.resolve().is_relative_to(base),'Path escapes destination' |
| dest.parent.mkdir(parents=True,exist_ok=True) |
| if dest.exists():assert not dest.is_symlink() and digest(dest)==sha,f'Refusing overwrite: {dest}' |
| else:dest.write_bytes(data) |
| count+=1 |
| assert not objects,f'Missing objects: {len(objects)}' |
| print(f'Verified and restored {count} files to {base}') |
| if __name__=='__main__':main() |
|
|
