garoupa 0.2101.12

Incremental cryptography and flexible hash

garoupa

Incremental cryptography and flexible hash

Latest version

Installation

as a standalone lib.

# Set up a virtualenv. 
python3.7 -m venv venv
source venv/bin/activate

# Install from PyPI...
pip install --upgrade pip
pip install -U garoupa

# ...or, install from updated source code.
pip install git+https://github.com/davips/garoupa

as an editable lib inside your project.

cd your-project
source venv/bin/activate
git clone https://github.com/davips/garoupa ../garoupa
pip install --upgrade pip
pip install -e ../garoupa

Examples

Creating flexible hashes

from garoupa import Hash

# Binary strings are hashed by MD5.
a = Hash(b"Some text.")
print(f"Hex:\n{a.hex}")
"""
Hex:
5f2b51ca2fdc5baa31ec02e002f69aec
"""

# A shorter base-62 identifier is also provided as default.
print(a.id, "=", a)
"""
2ta4DsTtzJxNXItOSQfcfE = 2ta4DsTtzJxNXItOSQfcfE
"""

# Integers are not hashed, they are directly mapped to the hash space.
print(a.n)
"""
126501587258562921197401139372367452908
"""

print(Hash(126501587258562921197401139372367452908), "=", a)
"""
2ta4DsTtzJxNXItOSQfcfE = 2ta4DsTtzJxNXItOSQfcfE
"""

b = Hash(340282366920938463463374607431768211455)  # Largest posible number.
print(b)
"""
7n42DGM5Tflk9n8mt7Fhc7
"""

Operations between flexible hashes

from garoupa import Hash

# Hashes can be multiplied.
a = Hash(b"Some text.")
b = Hash(b"Other text.")
c = a * b
print(f"{a} * {b} = {c}")
"""
2ta4DsTtzJxNXItOSQfcfE * 1s2qEnAwwi16V2hCUYV8dY = 3EYMMabJR2Aj8rUtPiZ1gO
"""

# Multiplication can be reverted by the inverse hash. Zero is the identity hash.
print(f"{b} * {b.inv} = {b * b.inv} = 0")
"""
1s2qEnAwwi16V2hCUYV8dY * 1he9mgDNZUsKtjzHTFTWsW = 0000000000000000000000 = 0
"""

print(f"{c} * {b.inv} = {c * b.inv} = {a} = a")
"""
3EYMMabJR2Aj8rUtPiZ1gO * 1he9mgDNZUsKtjzHTFTWsW = 2ta4DsTtzJxNXItOSQfcfE = 2ta4DsTtzJxNXItOSQfcfE = a
"""

print(f"{a.inv} * {c} = {a.inv * c} = {b} = b")
"""
2PMEzPHCsQn8cSxy31ohvo * 3EYMMabJR2Aj8rUtPiZ1gO = 1s2qEnAwwi16V2hCUYV8dY = 1s2qEnAwwi16V2hCUYV8dY = b
"""

# Division is shorthand for reversion.
print(f"{c} / {b} = {c / b} = a")
"""
3EYMMabJR2Aj8rUtPiZ1gO / 1s2qEnAwwi16V2hCUYV8dY = 2ta4DsTtzJxNXItOSQfcfE = a
"""

# Hash multiplication is not commutative.
print(f"{a * b} != {b * a}")
"""
3EYMMabJR2Aj8rUtPiZ1gO != 3SemNwugPbPPwm6wXaYFqi
"""

# Hash multiplication is associative.
print(f"{a * (b * c)} = {(a * b) * c}")
"""
021EieFLdrV69bPx1ddPJA = 021EieFLdrV69bPx1ddPJA
"""

Timing tradeoff startup/repetition

from timeit import timeit

from garoupa import Hash


def f():
    return Hash(12431434) * Hash(895784)


def f_compiled():
    return Hash(12431434, compiled=True) * Hash(895784, compiled=True)

t = timeit(f, number=1)
print("Normal warm up time:", round(t, 2), "s")
"""
Normal warm up time: 0.0 s
"""

t = timeit(f, number=100000)
print("Normal time:", round(t * 10, 2), "us")
"""
Normal time: 52.25 us
"""

t = timeit(f_compiled, number=1)
print("Compiled warm up time:", round(t, 2), "s")
"""
Compiled warm up time: 2.28 s
"""

t = timeit(f_compiled, number=100000)
print("Compiled time:", round(t * 10, 2), "us")
"""
Compiled time: 7.59 us
"""

Features / TODO

• Features / TODO