Source code for ensembl.utils.checksums

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"""Utils for common hash operations (often referred to as checksums) over files, e.g. MD5 or SHA128."""

import hashlib
from pathlib import Path

from ensembl.utils import StrPath




def get_file_hash(file_path: StrPath, algorithm: str = "md5") -> str:
    """Returns the hash value for a given file and hash algorithm.

    Args:
        file_path: File path to get the hash for.
        algorithm: Secure hash or message digest algorithm name.
    """
    hash_func = hashlib.new(algorithm)
    with Path(file_path).open("rb") as f:
        data_bytes = f.read()
    hash_func.update(data_bytes)
    return hash_func.hexdigest()





def validate_file_hash(file_path: StrPath, hash_value: str, algorithm: str = "md5") -> bool:
    """Returns true if the file's hash value is the same as the one provided for that hash
    algorithm, false otherwise.

    Args:
        file_path: Path to the file to validate.
        hash_value: Expected hash value.
        algorithm: Secure hash or message digest algorithm name.
    """
    file_hash = get_file_hash(file_path, algorithm)
    return file_hash == hash_value