py-libp2p/libp2p/io/msgio.py
2019-08-24 22:37:44 +02:00

17 lines
516 B
Python

import asyncio
SIZE_LEN_BYTES = 4
# TODO unify w/ https://github.com/libp2p/py-libp2p/blob/1aed52856f56a4b791696bbcbac31b5f9c2e88c9/libp2p/utils.py#L85-L99
def encode(msg_bytes: bytes) -> bytes:
len_prefix = len(msg_bytes).to_bytes(SIZE_LEN_BYTES, "big")
return len_prefix + msg_bytes
async def read_next_message(reader: asyncio.StreamReader) -> bytes:
len_bytes = await reader.readexactly(SIZE_LEN_BYTES)
len_int = int.from_bytes(len_bytes, "big")
return await reader.readexactly(len_int)