# -*- coding: utf-8 -*-
"""The hasher interface."""
from __future__ import unicode_literals
import abc
[docs]class BaseHasher(object):
"""Base class for objects that calculate hashes."""
NAME = 'base_hasher'
DESCRIPTION = 'Calculates a digest hash over input data.'
[docs] @abc.abstractmethod
def GetBinaryDigest(self):
"""Retrieves the digest of the hash function as a binary string.
Returns:
bytes: binary hash digest calculated over the data blocks passed to
Update().
"""
[docs] @abc.abstractmethod
def GetStringDigest(self):
"""Retrieves the digest of the hash function expressed as a Unicode string.
Returns:
str: string hash digest calculated over the data blocks passed to
Update(). The string consists of printable Unicode characters.
"""
[docs] @abc.abstractmethod
def Update(self, data):
"""Updates the current state of the hasher with a new block of data.
Repeated calls to update are equivalent to one single call with the
concatenation of the arguments.
Args:
data(bytes): data with which to update the context of the hasher.
"""