py-libp2p/libp2p/stream_muxer/mplex/mplex_stream.py

119 lines
3.6 KiB
Python

import asyncio
from .utils import get_flag
from ..muxed_stream_interface import IMuxedStream
class MplexStream(IMuxedStream):
# pylint: disable=too-many-instance-attributes
"""
reference: https://github.com/libp2p/go-mplex/blob/master/stream.go
"""
def __init__(self, stream_id, initiator, mplex_conn):
"""
create new MuxedStream in muxer
:param stream_id: stream stream id
:param initiator: boolean if this is an initiator
:param mplex_conn: muxed connection of this muxed_stream
"""
self.stream_id = stream_id
self.initiator = initiator
self.mplex_conn = mplex_conn
self.read_deadline = None
self.write_deadline = None
self.local_closed = False
self.remote_closed = False
self.stream_lock = asyncio.Lock()
async def read(self):
"""
read messages associated with stream from buffer til end of file
:return: bytes of input
"""
return await self.mplex_conn.read_buffer(self.stream_id)
async def write(self, data):
"""
write to stream
:return: number of bytes written
"""
print("Writing message")
print(self.stream_id)
print(self.mplex_conn.peer_id)
return await self.mplex_conn.send_message(
get_flag(self.initiator, "MESSAGE"), data, self.stream_id)
async def close(self):
"""
Closing a stream closes it for writing and closes the remote end for reading
but allows writing in the other direction.
:return: true if successful
"""
# TODO error handling with timeout
# TODO understand better how mutexes are used from go repo
await self.mplex_conn.send_message(get_flag(self.initiator, "CLOSE"), None, self.stream_id)
remote_lock = ""
async with self.stream_lock:
if self.local_closed:
return True
self.local_closed = True
remote_lock = self.remote_closed
if remote_lock:
async with self.mplex_conn.conn_lock:
self.mplex_conn.buffers.pop(self.stream_id)
return True
async def reset(self):
"""
closes both ends of the stream
tells this remote side to hang up
:return: true if successful
"""
# TODO understand better how mutexes are used here
# TODO understand the difference between close and reset
async with self.stream_lock:
if self.remote_closed and self.local_closed:
return True
if not self.remote_closed:
await self.mplex_conn.send_message(
get_flag(self.initiator, "RESET"), None, self.stream_id)
self.local_closed = True
self.remote_closed = True
async with self.mplex_conn.conn_lock:
self.mplex_conn.buffers.pop(self.stream_id, None)
return True
# TODO deadline not in use
def set_deadline(self, ttl):
"""
set deadline for muxed stream
:return: True if successful
"""
self.read_deadline = ttl
self.write_deadline = ttl
return True
def set_read_deadline(self, ttl):
"""
set read deadline for muxed stream
:return: True if successful
"""
self.read_deadline = ttl
return True
def set_write_deadline(self, ttl):
"""
set write deadline for muxed stream
:return: True if successful
"""
self.write_deadline = ttl
return True