Source code for virgil_sdk.utils.utils

# Copyright (C) 2016-2019 Virgil Security Inc.
#
# Lead Maintainer: Virgil Security Inc. <support@virgilsecurity.com>
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#     notice, this list of conditions and the following disclaimer.
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#     (2) Redistributions in binary form must reproduce the above copyright
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#     the documentation and/or other materials provided with the
#     distribution.
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#     contributors may be used to endorse or promote products derived from
#     this software without specific prior written permission.
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import base64
import binascii
import datetime
import json
import sys

if sys.version_info[0] == 2:
    from __builtin__ import unicode

    def normalize_string(data_str):
        if isinstance(data_str, unicode):
            return bytearray(data_str, "utf-8")

    def check_unicode(source):
        return isinstance(source, unicode)
else:
[docs] def normalize_string(data_str): return data_str
[docs] def check_unicode(source): return False
[docs]class Utils(object):
[docs] @staticmethod def b64_decode(source): """Decode base64, padding being optional. Args: source: Base64 data as an ASCII byte string Returns: The decoded byte string. """ try: if isinstance(source, bytes): return base64.urlsafe_b64decode(source) return base64.urlsafe_b64decode(bytearray(source, "utf-8")) except (binascii.Error, TypeError) as e: missing_padding = len(source) % 4 if missing_padding != 0: if isinstance(source, str) or check_unicode(source): source += '=' * (4 - missing_padding) if isinstance(source, bytes) or isinstance(source, bytearray): source += b'=' * (4 - missing_padding) if isinstance(source, bytes): return base64.urlsafe_b64decode(source) return base64.urlsafe_b64decode(bytearray(source, "utf-8"))
[docs] @staticmethod def b64_encode(source): """ Removes any `=` used as padding from the encoded string. Args: Data for encoding. Returns: Encoded data without '=' sign """ if isinstance(source, bytes): encoded = base64.urlsafe_b64encode(source) else: encoded = base64.urlsafe_b64encode(bytearray(source, "utf-8")) return bytearray(encoded).decode().rstrip("=")
[docs] @staticmethod def strtobytes(source): # type: (str) -> Tuple[*int] """Convert string to bytes tuple used for all crypto methods.""" return tuple(bytearray(source))
[docs] @classmethod def b64tobytes(cls, source): # type: (str) -> Tuple[*int] """Convert source to bytearray and encode using base64.""" return cls.strtobytes(cls.b64decode(source))
[docs] @staticmethod def b64encode(source): # type: (Union[str, bytes]) -> str """Convert source to bytearray and encode using base64.""" return base64.b64encode(bytearray(source)).decode("utf-8", "ignore")
[docs] @staticmethod def b64decode(source): # type: (Union[str, bytes]) -> str """Convert source to bytearray and decode using base64.""" if isinstance(source, bytes): return base64.b64decode(source) return base64.b64decode(bytearray(source, "utf-8"))
[docs] @staticmethod def json_loads(source): # type: (Union[str, bytes, bytearray]) -> dict """Convert source to bytearray and deserialize from json to python dict object.""" if isinstance(source, bytes): return json.loads(bytearray(source).decode()) return json.loads(bytearray(source, "utf-8").decode())
[docs] @staticmethod def json_dumps(source, *args, **kwargs): # type: (object) -> str """Convert python dict to json string""" return json.dumps(source, *args, **kwargs)
[docs] @staticmethod def to_timestamp(date): # type: (datetime) -> Union[int, str] epoch = datetime.datetime(1970, 1, 1) return int((date - epoch).total_seconds())
[docs] @staticmethod def raise_from(exception): """Supress long traceback for custom exceptions Python 3, show only important exception.""" exception.__cause__ = None raise exception
[docs] @staticmethod def normalize_string(source): return normalize_string(source)
[docs] @staticmethod def check_unicode(source): return check_unicode(source)