hashutils.py

import hashlib
from io import BytesIO

BLOCKSIZE = 65536


def digest_file(filename, hasher_alg=hashlib.sha1()):
    hasher = hasher_alg
    with open(filename, 'rb') as afile:
        buf = afile.read(BLOCKSIZE)
        while len(buf) > 0:
            hasher.update(buf)
            buf = afile.read(BLOCKSIZE)
    return hasher.hexdigest()


def digest_string(content, encoding='utf8', hasher_alg=hashlib.sha1()):
    hasher = hasher_alg
    content_io = BytesIO(content.encode(encoding))
    buf = content_io.read(BLOCKSIZE)
    while len(buf) > 0:
        hasher.update(buf)
        buf = content_io.read(BLOCKSIZE)
    return hasher.hexdigest()

hashutils_idiomatic.py

import hashlib
from io import BytesIO

BLOCKSIZE = 65536


def digest_file_pythonic(filename, hasher_alg=hashlib.sha1()):
    hasher = hasher_alg
    with open(filename, 'rb') as afile:
        for chunk in iter(lambda: afile.read(BLOCKSIZE), b''):
            hasher.update(chunk)
    return hasher.hexdigest()

  
def digest_string_pythonic(content, encoding='utf8', hasher_alg=hashlib.sha1()):
    hasher = hasher_alg
    content_io = BytesIO(content.encode(encoding))
    for chunk in iter(lambda: content_io.read(BLOCKSIZE), b''):
        hasher.update(chunk)
    return hasher.hexdigest()