pix.base32¶

Nix-specific base32 encoding and decoding.

Warning

This is not RFC 4648 base32. Nix uses a different alphabet and a different bit-extraction order. See Internals: Base32 for the full comparison.

Constants¶

`CHARS`¶

CHARS = "0123456789abcdfghijklmnpqrsvwxyz"

The 32-character Nix base32 alphabet. Notable omissions: e, o, t, u.

Functions¶

`encode(data: bytes) -> str`¶

Encode bytes to a Nix base32 string.

Output length: ceil(n * 8 / 5) characters for n input bytes.

Input size	Output size	Used for
20 bytes	32 chars	Store path hashes
32 bytes	52 chars	SHA-256 digests

from pix.base32 import encode

encode(b"\x00" * 20)
# '00000000000000000000000000000000'

import hashlib
digest = hashlib.sha256(b"hello").digest()
encode(digest)
# '094qif9n4cq4fdg459qzbhg1c6wywawwaaivx0k0x8xhbyx4vwic'

`decode(s: str) -> bytes`¶

Decode a Nix base32 string back to bytes.

Raises: ValueError if the string contains characters not in the Nix base32 alphabet.

from pix.base32 import decode

decode("094qif9n4cq4fdg459qzbhg1c6wywawwaaivx0k0x8xhbyx4vwic")
# b',\xf2M\xba_\xb0\xa3\x0e&\xe8;*\xc5\xb9\xe2\x9e\x1b\x16\x1e\\\x1f\xa7B^s\x043b\x93\x8b\x98$'

decode("00000000000000000000000000000000")
# b'\x00' * 20

Roundtrip¶

Encode and decode are inverse operations:

from pix.base32 import encode, decode

data = b"any bytes here"
assert decode(encode(data)) == data