Other approaches to obfuscating a value

fields.py

# https://github.com/potatolondon/django-gcloud-connectors/blob/b5279492b5b4b615640efa7cc5783a2cee0c1cbe/gcloudc/forms/fields.py#L145
import base64
import itertools


_VC_KEY = "1K94KG8L"  # Fixed key, don't change this!!


def model_path(obj):
    return obj._meta.db_table


def vc_encode(string):
    enc = []
    for i in range(len(string)):
        key_c = _VC_KEY[i % len(_VC_KEY)]
        enc_c = chr((ord(string[i]) + ord(key_c)) % 256)
        enc.append(enc_c)
    ret = base64.urlsafe_b64encode("".join(enc).encode("utf-8")).decode("ascii")
    return ret


def vc_decode(enc):
    dec = []
    enc = base64.urlsafe_b64decode(enc).decode("utf-8")
    for i in range(len(enc)):
        key_c = _VC_KEY[i % len(_VC_KEY)]
        dec_c = chr((256 + ord(enc[i]) - ord(key_c)) % 256)
        dec.append(dec_c)
    return "".join(dec)


_dbux_key = tuple(ord(c) for c in _VC_KEY)


def bux_encode(value) -> str:
    caesars = itertools.cycle(_dbux_key)
    points = bytearray((ord(c) + next(caesars)) % 256 for c in value)
    result = base64.urlsafe_b64encode(points).decode('ascii')

    return result


def bux_decode(value) -> str:
    caesars = itertools.cycle(_dbux_key)
    points = base64.urlsafe_b64decode(value.encode('ascii'))
    points = bytearray((256 + p - next(caesars)) % 256 for p in points)
    result = points.decode('utf-8')

    return result


def simple_encode(value) -> str:
    return base64.urlsafe_b64encode(value.encode('utf-8')).decode('ascii')


def simple_decode(value) -> str:
    return base64.urlsafe_b64decode(value.encode('ascii')).decode('utf-8')


import unittest


class PotatoTestCase(unittest.TestCase):
    def test_encode(self):
        result = vc_encode('django_user|123456789')

        self.assertEqual(result, 'wpXCtcKawqLCssK2wpfDgcKkwrDCq8KwfHlrwoBmwoFwbMKE')

    def test_decode(self):
        result = vc_decode('wpXCtcKawqLCssK2wpfDgcKkwrDCq8KwfHlrwoBmwoFwbMKE')

        self.assertEqual(result, 'django_user|123456789')


class BuxtonTestCase(unittest.TestCase):
    def test_encode(self):
        result = bux_encode('django_user|123456789')

        self.assertEqual(result, 'lbWaorK2l8GksKuwfHlrgGaBcGyE')

    def test_decode(self):
        result = bux_decode('lbWaorK2l8GksKuwfHlrgGaBcGyE')

        self.assertEqual(result, 'django_user|123456789')

    def test_dbux_key(self):
        self.assertEqual(_dbux_key,  (49, 75, 57, 52, 75, 71, 56, 76))


class SimpleTestCase(unittest.TestCase):
    def test_encode(self):
        result = simple_encode('django_user|123456789')

        self.assertEqual(result, 'ZGphbmdvX3VzZXJ8MTIzNDU2Nzg5')

    def test_decode(self):
        result = simple_decode('ZGphbmdvX3VzZXJ8MTIzNDU2Nzg5')

        self.assertEqual(result, 'django_user|123456789')

import timeit


speed_tests = [
    'vc_encode("django_user|123456789")',
    'vc_decode("wpXCtcKawqLCssK2wpfDgcKkwrDCq8KwfHlrwoBmwoFwbMKE")',
    'bux_encode("django_user|123456789")',
    'bux_decode("lbWaorK2l8GksKuwfHlrgGaBcGyE")',
    'simple_encode("django_user|123456789")',
    'simple_decode("ZGphbmdvX3VzZXJ8MTIzNDU2Nzg5")',
]


if __name__ == '__main__':

    for stmt in speed_tests:
        print('Timing', stmt)
        print(timeit.repeat(stmt, repeat=3, number=100000, globals=globals()))

    unittest.main()