96 lines
2.8 KiB
Python
96 lines
2.8 KiB
Python
|
import asyncio
|
||
|
|
from typing import Optional, cast
|
||
|
|
|
||
|
|
from .helpers import set_exception
|
||
|
|
from .tcp_helpers import tcp_nodelay
|
||
|
|
|
||
|
|
|
||
|
|
class BaseProtocol(asyncio.Protocol):
|
||
|
|
__slots__ = (
|
||
|
|
"_loop",
|
||
|
|
"_paused",
|
||
|
|
"_drain_waiter",
|
||
|
|
"_connection_lost",
|
||
|
|
"_reading_paused",
|
||
|
|
"transport",
|
||
|
|
)
|
||
|
|
|
||
|
|
def __init__(self, loop: asyncio.AbstractEventLoop) -> None:
|
||
|
|
self._loop: asyncio.AbstractEventLoop = loop
|
||
|
|
self._paused = False
|
||
|
|
self._drain_waiter: Optional[asyncio.Future[None]] = None
|
||
|
|
self._reading_paused = False
|
||
|
|
|
||
|
|
self.transport: Optional[asyncio.Transport] = None
|
||
|
|
|
||
|
|
@property
|
||
|
|
def connected(self) -> bool:
|
||
|
|
"""Return True if the connection is open."""
|
||
|
|
return self.transport is not None
|
||
|
|
|
||
|
|
def pause_writing(self) -> None:
|
||
|
|
assert not self._paused
|
||
|
|
self._paused = True
|
||
|
|
|
||
|
|
def resume_writing(self) -> None:
|
||
|
|
assert self._paused
|
||
|
|
self._paused = False
|
||
|
|
|
||
|
|
waiter = self._drain_waiter
|
||
|
|
if waiter is not None:
|
||
|
|
self._drain_waiter = None
|
||
|
|
if not waiter.done():
|
||
|
|
waiter.set_result(None)
|
||
|
|
|
||
|
|
def pause_reading(self) -> None:
|
||
|
|
if not self._reading_paused and self.transport is not None:
|
||
|
|
try:
|
||
|
|
self.transport.pause_reading()
|
||
|
|
except (AttributeError, NotImplementedError, RuntimeError):
|
||
|
|
pass
|
||
|
|
self._reading_paused = True
|
||
|
|
|
||
|
|
def resume_reading(self) -> None:
|
||
|
|
if self._reading_paused and self.transport is not None:
|
||
|
|
try:
|
||
|
|
self.transport.resume_reading()
|
||
|
|
except (AttributeError, NotImplementedError, RuntimeError):
|
||
|
|
pass
|
||
|
|
self._reading_paused = False
|
||
|
|
|
||
|
|
def connection_made(self, transport: asyncio.BaseTransport) -> None:
|
||
|
|
tr = cast(asyncio.Transport, transport)
|
||
|
|
tcp_nodelay(tr, True)
|
||
|
|
self.transport = tr
|
||
|
|
|
||
|
|
def connection_lost(self, exc: Optional[BaseException]) -> None:
|
||
|
|
# Wake up the writer if currently paused.
|
||
|
|
self.transport = None
|
||
|
|
if not self._paused:
|
||
|
|
return
|
||
|
|
waiter = self._drain_waiter
|
||
|
|
if waiter is None:
|
||
|
|
return
|
||
|
|
self._drain_waiter = None
|
||
|
|
if waiter.done():
|
||
|
|
return
|
||
|
|
if exc is None:
|
||
|
|
waiter.set_result(None)
|
||
|
|
else:
|
||
|
|
set_exception(
|
||
|
|
waiter,
|
||
|
|
ConnectionError("Connection lost"),
|
||
|
|
exc,
|
||
|
|
)
|
||
|
|
|
||
|
|
async def _drain_helper(self) -> None:
|
||
|
|
if not self.connected:
|
||
|
|
raise ConnectionResetError("Connection lost")
|
||
|
|
if not self._paused:
|
||
|
|
return
|
||
|
|
waiter = self._drain_waiter
|
||
|
|
if waiter is None:
|
||
|
|
waiter = self._loop.create_future()
|
||
|
|
self._drain_waiter = waiter
|
||
|
|
await asyncio.shield(waiter)
|