| |
| """Verify downloaded volumes, then extract without concatenating a large archive.""" |
| import hashlib,json,subprocess,sys |
| from pathlib import Path |
| root=Path(__file__).resolve().parent |
| m=json.loads((root/'backup-manifest.json').read_text()) |
| if not m['complete']: raise SystemExit('This backup is still uploading.') |
| for part in m['parts']: |
| p=root/part['path']; h=hashlib.sha256() |
| with p.open('rb') as f: |
| for block in iter(lambda:f.read(4*1024*1024),b''):h.update(block) |
| if p.stat().st_size!=part['size'] or h.hexdigest()!=part['sha256']: |
| raise SystemExit('Missing/corrupt volume or unmaterialized LFS pointer: '+str(p)) |
| print('All volume checksums verified.',flush=True) |
| out=Path(sys.argv[1]).resolve() if len(sys.argv)>1 else root |
| out.mkdir(parents=True,exist_ok=True) |
| z=subprocess.Popen(['zstd','-d','-c'],stdin=subprocess.PIPE,stdout=subprocess.PIPE) |
| t=subprocess.Popen(['tar','-xf','-','-C',str(out)],stdin=z.stdout) |
| z.stdout.close() |
| try: |
| for part in m['parts']: |
| with (root/part['path']).open('rb') as f: |
| for block in iter(lambda:f.read(4*1024*1024),b''):z.stdin.write(block) |
| z.stdin.close() |
| if z.wait()!=0 or t.wait()!=0:raise SystemExit('Extraction failed.') |
| finally: |
| for proc in [z,t]: |
| if proc.poll() is None:proc.terminate() |
| print('Restored the archived directories to',out) |
|
|
