File size: 2,475 Bytes
31112ad | 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 71 72 73 74 75 76 77 | import hashlib
from pathlib import Path
def compute_sha256(file_path, expected_hash=None, chunk_size=8192):
"""
Compute the SHA256 hash of a file and optionally verify it.
Args:
file_path (str or Path): Path to the file to hash
expected_hash (str, optional): Expected SHA256 hash to verify against
chunk_size (int): Size of chunks to read (default 8KB for memory efficiency)
Returns:
str: The computed SHA256 hash (lowercase hexadecimal)
Raises:
FileNotFoundError: If the file doesn't exist
ValueError: If expected_hash is provided and doesn't match
Example:
>>> # Just compute the hash
>>> hash_value = compute_sha256("model.bin")
>>> print(f"SHA256: {hash_value}")
>>> # Compute and verify
>>> try:
>>> hash_value = compute_sha256("model.bin",
>>> expected_hash="abc123...")
>>> print("File verified successfully!")
>>> except ValueError as e:
>>> print(f"Verification failed: {e}")
"""
file_path = Path(file_path)
if not file_path.exists():
raise FileNotFoundError(f"File not found: {file_path}")
# Create SHA256 hash object
sha256_hash = hashlib.sha256()
# Read file in chunks to handle large files efficiently
with open(file_path, "rb") as f:
while chunk := f.read(chunk_size):
sha256_hash.update(chunk)
# Get the hexadecimal representation
computed_hash = sha256_hash.hexdigest()
# Verify if expected hash is provided
if expected_hash is not None:
expected_hash = expected_hash.lower().strip()
if computed_hash != expected_hash:
raise ValueError(
f"Hash mismatch!\n"
f"Expected: {expected_hash}\n"
f"Computed: {computed_hash}"
)
print(f"✓ Hash verified successfully: {computed_hash}")
return computed_hash
if __name__ == "__main__":
# Example usage
import sys
file_path = "c:/temp/hunyuan_15_upsampler.safetensors"
expected_hash = "691dc1b81b49d942e2eb95e6d61b91321e17b868536eaa4e843db6e406390411"
try:
hash_value = compute_sha256(file_path, expected_hash)
print(f"SHA256: {hash_value}")
except (FileNotFoundError, ValueError) as e:
print(f"Error: {e}")
sys.exit(1)
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