base32.py

"""
Base32 encoding and decoding

https://en.wikipedia.org/wiki/Base32
"""

B32_CHARSET="ABCDEFGHIJKLMNOPQRSTUVWXYZ234567"


defbase32_encode(data: bytes) ->bytes:
"""
 >>> base32_encode(b"Hello World!")
 b'JBSWY3DPEBLW64TMMQQQ===='
 >>> base32_encode(b"123456")
 b'GEZDGNBVGY======'
 >>> base32_encode(b"some long complex string")
 b'ONXW2ZJANRXW4ZZAMNXW24DMMV4CA43UOJUW4ZY='
 """
binary_data="".join(bin(ord(d))[2:].zfill(8) fordindata.decode("utf-8"))
binary_data=binary_data.ljust(5* ((len(binary_data) //5) +1), "0")
b32_chunks=map("".join, zip(*[iter(binary_data)] *5))
b32_result="".join(B32_CHARSET[int(chunk, 2)] forchunkinb32_chunks)
returnbytes(b32_result.ljust(8* ((len(b32_result) //8) +1), "="), "utf-8")


defbase32_decode(data: bytes) ->bytes:
"""
 >>> base32_decode(b'JBSWY3DPEBLW64TMMQQQ====')
 b'Hello World!'
 >>> base32_decode(b'GEZDGNBVGY======')
 b'123456'
 >>> base32_decode(b'ONXW2ZJANRXW4ZZAMNXW24DMMV4CA43UOJUW4ZY=')
 b'some long complex string'
 """
binary_chunks="".join(
bin(B32_CHARSET.index(_d))[2:].zfill(5)
for_dindata.decode("utf-8").strip("=")
 )
binary_data=list(map("".join, zip(*[iter(binary_chunks)] *8)))
returnbytes("".join([chr(int(_d, 2)) for_dinbinary_data]), "utf-8")


if__name__=="__main__":
importdoctest

doctest.testmod()