Class NodeSocketTransport

src/py/pyodide/_nodesock_transport.py:12–191

asyncio Transport backed by a NodeSockFS socket.

class NodeSocketTransport(asyncio.Transport):
    """asyncio Transport backed by a NodeSockFS socket."""

    def __init__(
        self,
        loop: asyncio.AbstractEventLoop,
        sock: Any,  # socket.socket
        protocol: asyncio.BaseProtocol,
        waiter: asyncio.Future[None] | None = None,
        extra: dict[str, Any] | None = None,
    ):
        super().__init__(extra)
        self._loop = loop
        self._sock = sock
        self._sock_fd = sock.fileno()
        self._protocol = protocol
        self._closed = False
        self._paused = True  # start paused; resume_reading() will kick off reads
        self._read_task: asyncio.Task[None] | None = None

        # self._extra is used in `get_extra_info` function.
        # We just swallow exceptions following the _SelectorTransport implementation in CPython
        # https://github.com/python/cpython/blob/fbfc6ccb0abf362a0ecdc02cd0aa2d16c1a4ce44/Lib/asyncio/selector_events.py#L780-L787
        self._extra.setdefault("socket", sock)  # type: ignore[attr-defined]
        try:
            self._extra.setdefault("sockname", sock.getsockname())  # type: ignore[attr-defined]
        except Exception:
            pass
        try:
            self._extra.setdefault("peername", sock.getpeername())  # type: ignore[attr-defined]
        except Exception:
            pass
        loop.call_soon(self._protocol.connection_made, self)
        if waiter is not None:
            loop.call_soon(self._resolve_waiter, waiter)
        loop.call_soon(self._start_reading)

    @staticmethod
    def _resolve_waiter(waiter: asyncio.Future[None]) -> None:
        if not waiter.done():
            waiter.set_result(None)

    # ------------------------------------------------------------------
    # BaseTransport
    # ------------------------------------------------------------------

    def is_closing(self) -> bool:
        # We don't separate _closing and _closed state
        # because the buffer is managed by Node.js not Python
        # so no drain is handled by Python
        return self._closed

    def close(self) -> None:
        self._force_close(None)

    def abort(self) -> None:
        self._force_close(None)