| """Utilities to efficiently compute the SHA 256 hash of a bunch of bytes.""" | |
| from typing import BinaryIO, Optional | |
| from .insecure_hashlib import sha256 | |
| def sha_fileobj(fileobj: BinaryIO, chunk_size: Optional[int] = None) -> bytes: | |
| """ | |
| Computes the sha256 hash of the given file object, by chunks of size `chunk_size`. | |
| Args: | |
| fileobj (file-like object): | |
| The File object to compute sha256 for, typically obtained with `open(path, "rb")` | |
| chunk_size (`int`, *optional*): | |
| The number of bytes to read from `fileobj` at once, defaults to 1MB. | |
| Returns: | |
| `bytes`: `fileobj`'s sha256 hash as bytes | |
| """ | |
| chunk_size = chunk_size if chunk_size is not None else 1024 * 1024 | |
| sha = sha256() | |
| while True: | |
| chunk = fileobj.read(chunk_size) | |
| sha.update(chunk) | |
| if not chunk: | |
| break | |
| return sha.digest() | |