Binary values¶

Nothing here decodes. KEYS, ARGV and every Lua string are byte strings, so a bytes argument arrives in the script as exactly those bytes and comes back as exactly those bytes.

import zlib


@script
def cache_compressed(key: Key, blob: bytes, ttl: int) -> int:
    redis.set(key, blob)
    redis.expire(key, ttl)
    return len(blob)


cache_compressed(client, key="report:42", blob=zlib.compress(report), ttl=300)

A bytes annotation is a passthrough: no tonumber, no decoding, no round trip through text. memoryview is accepted the same way. A bytes literal in a body is emitted as numeric escapes — b"\x00\xff" becomes '\000\255' — so it survives the journey to the server, where the script itself travels as text.

This is a guarantee rather than an observation: tests/test_binary.py round-trips non-UTF-8 bytes through ARGV, through a stored value, and back out of a returned GETRANGE, against both fakeredis and a real server.