Datasets:
File size: 3,020 Bytes
8c03b76 | 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 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 | #!/usr/bin/env python3
"""Inspect a source asset, or explicitly download a commit-pinned GitHub asset."""
import argparse
import hashlib
import json
from pathlib import Path
import urllib.parse
import urllib.request
def github_raw_url(url):
parsed = urllib.parse.urlsplit(url)
parts = parsed.path.split('/')
if parsed.hostname != 'github.com' or len(parts) < 6 or parts[3] != 'blob':
raise ValueError('Expected a GitHub blob URL')
owner, repo, revision = parts[1], parts[2], parts[4]
if len(revision) != 40 or any(c not in '0123456789abcdef' for c in revision.lower()):
raise ValueError('Source URL is not pinned to a full commit')
raw_path = '/'.join([owner, repo, revision] + parts[5:])
return 'https://raw.githubusercontent.com/' + urllib.parse.quote(urllib.parse.unquote(raw_path), safe='/')
def main():
parser = argparse.ArgumentParser(description=__doc__)
parser.add_argument('manifest', type=Path)
parser.add_argument('sample_id')
parser.add_argument('--download', action='store_true')
parser.add_argument('--output', type=Path)
args = parser.parse_args()
record = next((r for r in map(json.loads, args.manifest.open()) if r['sample_id'] == args.sample_id), None)
if record is None:
parser.error('Sample ID not found')
info = {k: record[k] for k in ['sample_id', 'source_asset_id', 'source_url', 'source_file_type',
'source_sha256', 'historical_license', 'observed_license_url', 'provenance_flags']}
if record['source_group'] == 'github':
info['download_url'] = github_raw_url(record['source_url'])
else:
info['download_method'] = 'Use the original Sketchfab page and its official download flow.'
print(json.dumps(info, indent=2, ensure_ascii=False))
if not args.download:
return
if record['source_group'] != 'github':
parser.error('Automatic Sketchfab downloads are not implemented; use the official source flow.')
if args.output is None:
parser.error('--download requires --output')
if args.output.exists():
parser.error('Output already exists; select a new path')
partial = args.output.with_name(args.output.name + '.partial')
digest = hashlib.sha256()
created = False
try:
with partial.open('xb') as out:
created = True
with urllib.request.urlopen(info['download_url'], timeout=60) as response:
for chunk in iter(lambda: response.read(1024 * 1024), b''):
out.write(chunk)
digest.update(chunk)
if digest.hexdigest() != record['source_sha256']:
raise ValueError('Source SHA-256 mismatch; upstream content or a Git LFS pointer may differ')
partial.rename(args.output)
except Exception:
if created and partial.exists():
partial.unlink()
raise
print('Verified source asset saved to ' + str(args.output))
if __name__ == '__main__':
main()
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