Add frozen Main17 features assets (13-13)

restore_patch_features.py

@@ -0,0 +1,48 @@
+"""Reassemble uploaded byte shards into the exact original NPY file."""
+import argparse,hashlib,json,shutil
+from pathlib import Path
+
+def sha(path):
+    h=hashlib.sha256()
+    with path.open('rb') as stream:
+        while data:=stream.read(8*1024**2): h.update(data)
+    return h.hexdigest()
+
+def main():
+    parser=argparse.ArgumentParser(description=__doc__)
+    parser.add_argument('--root',type=Path,default=Path(__file__).resolve().parent)
+    args=parser.parse_args();root=args.root.resolve()
+    manifest=json.loads((root/'asset_manifest.json').read_text(encoding='utf-8'))
+    for item in manifest.get('reassemble',[]):
+        target=(root/item['path']).resolve()
+        if not target.is_relative_to(root):raise ValueError('Path escapes asset root')
+        target.parent.mkdir(parents=True,exist_ok=True)
+        if target.exists():
+            if target.stat().st_size!=item['bytes'] or sha(target)!=item['sha256']:
+                raise ValueError('Existing output differs; refusing overwrite')
+            print('Already verified:',item['path']);continue
+        if shutil.disk_usage(target.parent).free<item['bytes']:
+            raise RuntimeError('Insufficient space for the restored NPY; shards are retained')
+        temp=target.with_name(target.name+'.restoring')
+        digest=hashlib.sha256();written=0
+        try:
+            with temp.open('xb') as output:
+                for part in item['parts']:
+                    if part['byte_offset']!=written:raise ValueError('Non-contiguous shards')
+                    source=(root/part['path']).resolve()
+                    if not source.is_relative_to(root) or source.stat().st_size!=part['bytes']:
+                        raise ValueError('Missing or invalid shard')
+                    part_hash=hashlib.sha256()
+                    with source.open('rb') as stream:
+                        while data:=stream.read(8*1024**2):
+                            output.write(data);part_hash.update(data);digest.update(data);written+=len(data)
+                    if part_hash.hexdigest()!=part['sha256']:raise ValueError('Shard checksum mismatch')
+            if written!=item['bytes'] or digest.hexdigest()!=item['sha256']:
+                raise ValueError('Restored NPY checksum mismatch')
+            temp.rename(target)
+        except Exception:
+            # Retain partial output for inspection; never remove existing user files.
+            raise
+        print('Restored and verified:',item['path'])
+
+if __name__=='__main__':main()