import asyncio import contextvars import enum import logging import socket import time from contextlib import suppress from dataclasses import astuple, dataclass from typing import Any, Callable, Coroutine, Dict, Iterable, List, Optional, Type, Union import async_timeout from google.protobuf import message import aioesphomeapi.host_resolver as hr from ._frame_helper import ( APIFrameHelper, APINoiseFrameHelper, APIPlaintextFrameHelper, Packet, ) from .api_pb2 import ( # type: ignore ConnectRequest, ConnectResponse, DisconnectRequest, DisconnectResponse, GetTimeRequest, GetTimeResponse, HelloRequest, HelloResponse, PingRequest, PingResponse, ) from .core import ( MESSAGE_TYPE_TO_PROTO, APIConnectionError, BadNameAPIError, HandshakeAPIError, InvalidAuthAPIError, PingFailedAPIError, ProtocolAPIError, ReadFailedAPIError, ResolveAPIError, SocketAPIError, TimeoutAPIError, ) from .model import APIVersion _LOGGER = logging.getLogger(__name__) BUFFER_SIZE = 1024 * 1024 # Set buffer limit to 1MB INTERNAL_MESSAGE_TYPES = {GetTimeRequest, PingRequest, DisconnectRequest} PROTO_TO_MESSAGE_TYPE = {v: k for k, v in MESSAGE_TYPE_TO_PROTO.items()} in_do_connect: contextvars.ContextVar[Optional[bool]] = contextvars.ContextVar( "in_do_connect" ) @dataclass class ConnectionParams: address: str port: int password: Optional[str] client_info: str keepalive: float zeroconf_instance: hr.ZeroconfInstanceType noise_psk: Optional[str] expected_name: Optional[str] class ConnectionState(enum.Enum): # The connection is initialized, but connect() wasn't called yet INITIALIZED = 0 # Internal state, SOCKET_OPENED = 1 # The connection has been established, data can be exchanged CONNECTED = 2 CLOSED = 3 class APIConnection: """This class represents _one_ connection to a remote native API device. An instance of this class may only be used once, for every new connection a new instance should be established. """ def __init__( self, params: ConnectionParams, on_stop: Callable[[bool], Coroutine[Any, Any, None]], log_name: Optional[str] = None, ) -> None: self._params = params self.on_stop: Optional[Callable[[bool], Coroutine[Any, Any, None]]] = on_stop self._on_stop_task: Optional[asyncio.Task[None]] = None self._socket: Optional[socket.socket] = None self._frame_helper: Optional[APIFrameHelper] = None self._api_version: Optional[APIVersion] = None self._connection_state = ConnectionState.INITIALIZED self._is_authenticated = False # Store whether connect() has completed # Used so that on_stop is _not_ called if an error occurs during connect() self._connect_complete = False # Message handlers currently subscribed to incoming messages self._message_handlers: Dict[Any, List[Callable[[message.Message], None]]] = {} # The friendly name to show for this connection in the logs self.log_name = log_name or params.address # Handlers currently subscribed to exceptions in the read task self._read_exception_handlers: List[Callable[[Exception], None]] = [] self._ping_stop_event = asyncio.Event() self._connect_task: Optional[asyncio.Task[None]] = None self._keep_alive_task: Optional[asyncio.Task[None]] = None self._fatal_exception: Optional[Exception] = None self._expected_disconnect = False @property def connection_state(self) -> ConnectionState: """Return the current connection state.""" return self._connection_state def set_log_name(self, name: str) -> None: """Set the friendly log name for this connection.""" self.log_name = name def _cleanup(self) -> None: """Clean up all resources that have been allocated. Safe to call multiple times. """ _LOGGER.debug("Cleaning up connection to %s", self.log_name) # If we are being called from do_connect we # need to make sure we don't cancel the task # that called us if self._connect_task is not None and not in_do_connect.get(False): self._connect_task.cancel() self._connect_task = None if self._keep_alive_task is not None: self._keep_alive_task.cancel() self._keep_alive_task = None if self._frame_helper is not None: self._frame_helper.close() self._frame_helper = None if self._socket is not None: self._socket.close() self._socket = None if self.on_stop and self._connect_complete: def _remove_on_stop_task(_fut: asyncio.Future[None]) -> None: """Remove the stop task. We need to do this because the asyncio does not hold a strong reference to the task, so it can be garbage collected unexpectedly. """ self._on_stop_task = None # Ensure on_stop is called only once self._on_stop_task = asyncio.create_task( self.on_stop(self._expected_disconnect) ) self._on_stop_task.add_done_callback(_remove_on_stop_task) self.on_stop = None # Note: we don't explicitly cancel the ping/read task here # That's because if not written right the ping/read task could cancel # themselves, effectively ending execution after _cleanup which may be unexpected self._ping_stop_event.set() async def _connect_resolve_host(self) -> hr.AddrInfo: """Step 1 in connect process: resolve the address.""" try: coro = hr.async_resolve_host( self._params.address, self._params.port, self._params.zeroconf_instance, ) async with async_timeout.timeout(30.0): return await coro except asyncio.TimeoutError as err: raise ResolveAPIError( f"Timeout while resolving IP address for {self.log_name}" ) from err async def _connect_socket_connect(self, addr: hr.AddrInfo) -> None: """Step 2 in connect process: connect the socket.""" self._socket = socket.socket( family=addr.family, type=addr.type, proto=addr.proto ) self._socket.setblocking(False) self._socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1) # Try to reduce the pressure on esphome device as it measures # ram in bytes and we measure ram in megabytes. try: self._socket.setsockopt(socket.SOL_SOCKET, socket.SO_RCVBUF, BUFFER_SIZE) except OSError as err: _LOGGER.warning( "%s: Failed to set socket receive buffer size: %s", self.log_name, err, ) _LOGGER.debug( "%s: Connecting to %s:%s (%s)", self.log_name, self._params.address, self._params.port, addr, ) sockaddr = astuple(addr.sockaddr) try: coro = asyncio.get_event_loop().sock_connect(self._socket, sockaddr) async with async_timeout.timeout(30.0): await coro except OSError as err: raise SocketAPIError(f"Error connecting to {sockaddr}: {err}") from err except asyncio.TimeoutError as err: raise SocketAPIError(f"Timeout while connecting to {sockaddr}") from err _LOGGER.debug( "%s: Opened socket to %s:%s (%s)", self.log_name, self._params.address, self._params.port, addr, ) async def _connect_init_frame_helper(self) -> None: """Step 3 in connect process: initialize the frame helper and init read loop.""" fh: Union[APIPlaintextFrameHelper, APINoiseFrameHelper] loop = asyncio.get_event_loop() if self._params.noise_psk is None: _, fh = await loop.create_connection( lambda: APIPlaintextFrameHelper( on_pkt=self._process_packet, on_error=self._report_fatal_error, ), sock=self._socket, ) else: _, fh = await loop.create_connection( lambda: APINoiseFrameHelper( noise_psk=self._params.noise_psk, expected_name=self._params.expected_name, on_pkt=self._process_packet, on_error=self._report_fatal_error, ), sock=self._socket, ) self._frame_helper = fh self._connection_state = ConnectionState.SOCKET_OPENED try: async with async_timeout.timeout(30.0): await fh.perform_handshake() except OSError as err: raise HandshakeAPIError(f"Handshake failed: {err}") from err except asyncio.TimeoutError as err: raise TimeoutAPIError("Handshake timed out") from err async def _connect_hello(self) -> None: """Step 4 in connect process: send hello and get api version.""" hello = HelloRequest() hello.client_info = self._params.client_info hello.api_version_major = 1 hello.api_version_minor = 7 try: resp = await self.send_message_await_response(hello, HelloResponse) except TimeoutAPIError as err: raise TimeoutAPIError("Hello timed out") from err _LOGGER.debug( "%s: Successfully connected ('%s' API=%s.%s)", self.log_name, resp.server_info, resp.api_version_major, resp.api_version_minor, ) self._api_version = APIVersion(resp.api_version_major, resp.api_version_minor) if self._api_version.major > 2: _LOGGER.error( "%s: Incompatible version %s! Closing connection", self.log_name, self._api_version.major, ) raise APIConnectionError("Incompatible API version.") if ( self._params.expected_name is not None and resp.name != "" and resp.name != self._params.expected_name ): raise BadNameAPIError( f"Server sent a different name '{resp.name}'", resp.name ) async def _connect_start_ping(self) -> None: """Step 5 in connect process: start the ping loop.""" async def _keep_alive_loop() -> None: while self._is_socket_open: # Wait for keepalive seconds, or ping stop event, whichever happens first try: async with async_timeout.timeout(self._params.keepalive): await self._ping_stop_event.wait() except asyncio.TimeoutError: pass # Re-check connection state if not self._is_socket_open or self._ping_stop_event.is_set(): return try: await self._ping() except TimeoutAPIError: _LOGGER.debug("%s: Ping timed out!", self.log_name) self._report_fatal_error(PingFailedAPIError()) return except APIConnectionError as err: _LOGGER.debug("%s: Ping Failed: %s", self.log_name, err) self._report_fatal_error(err) return except Exception as err: # pylint: disable=broad-except _LOGGER.error( "%s: Unexpected error during ping:", self.log_name, exc_info=True, ) self._report_fatal_error(err) return self._keep_alive_task = asyncio.create_task(_keep_alive_loop()) async def connect(self, *, login: bool) -> None: if self._connection_state != ConnectionState.INITIALIZED: raise ValueError( "Connection can only be used once, connection is not in init state" ) async def _do_connect() -> None: in_do_connect.set(True) addr = await self._connect_resolve_host() await self._connect_socket_connect(addr) await self._connect_init_frame_helper() await self._connect_hello() await self._connect_start_ping() if login: await self.login(check_connected=False) self._connect_task = asyncio.create_task(_do_connect()) try: # Allow 2 minutes for connect; this is only as a last measure # to protect from issues if some part of the connect process mistakenly # does not have a timeout async with async_timeout.timeout(120.0): await self._connect_task except asyncio.CancelledError: # If the task was cancelled, we need to clean up the connection # and raise the CancelledError self._connection_state = ConnectionState.CLOSED self._cleanup() raise self._fatal_exception or APIConnectionError("Connection cancelled") except Exception: # pylint: disable=broad-except # Always clean up the connection if an error occured during connect self._connection_state = ConnectionState.CLOSED self._cleanup() raise self._connection_state = ConnectionState.CONNECTED self._connect_complete = True async def login(self, check_connected: bool = True) -> None: """Send a login (ConnectRequest) and await the response.""" if check_connected: # On first connect, we don't want to check if we're connected # because we don't set the connection state until after login # is complete self._check_connected() if self._is_authenticated: raise APIConnectionError("Already logged in!") connect = ConnectRequest() if self._params.password is not None: connect.password = self._params.password try: resp = await self.send_message_await_response(connect, ConnectResponse) except TimeoutAPIError as err: # After a timeout for connect the connection can no longer be used # We don't know what state the device may be in after ConnectRequest # was already sent _LOGGER.debug("%s: Login timed out", self.log_name) self._report_fatal_error(err) raise if resp.invalid_password: raise InvalidAuthAPIError("Invalid password!") self._is_authenticated = True def _check_connected(self) -> None: if self._connection_state != ConnectionState.CONNECTED: raise APIConnectionError("Must be connected!") @property def _is_socket_open(self) -> bool: return self._connection_state in ( ConnectionState.SOCKET_OPENED, ConnectionState.CONNECTED, ) @property def is_connected(self) -> bool: return self._connection_state == ConnectionState.CONNECTED @property def is_authenticated(self) -> bool: return self.is_connected and self._is_authenticated def send_message(self, msg: message.Message) -> None: """Send a protobuf message to the remote.""" if not self._is_socket_open: raise APIConnectionError( f"Connection isn't established yet ({self._connection_state})" ) frame_helper = self._frame_helper assert frame_helper is not None message_type = PROTO_TO_MESSAGE_TYPE.get(type(msg)) if not message_type: raise ValueError(f"Message type id not found for type {type(msg)}") encoded = msg.SerializeToString() _LOGGER.debug("%s: Sending %s: %s", self._params.address, type(msg), str(msg)) try: frame_helper.write_packet( Packet( type=message_type, data=encoded, ) ) except SocketAPIError as err: # pylint: disable=broad-except # If writing packet fails, we don't know what state the frames # are in anymore and we have to close the connection _LOGGER.info("%s: Error writing packet: %s", self.log_name, err) self._report_fatal_error(err) raise def add_message_callback( self, on_message: Callable[[Any], None], msg_types: Iterable[Type[Any]] ) -> Callable[[], None]: """Add a message callback.""" for msg_type in msg_types: self._message_handlers.setdefault(msg_type, []).append(on_message) def unsub() -> None: for msg_type in msg_types: self._message_handlers[msg_type].remove(on_message) return unsub def remove_message_callback( self, on_message: Callable[[Any], None], msg_types: Iterable[Type[Any]] ) -> None: """Remove a message callback.""" for msg_type in msg_types: self._message_handlers[msg_type].remove(on_message) def send_message_callback_response( self, send_msg: message.Message, on_message: Callable[[Any], None], msg_types: Iterable[Type[Any]], ) -> None: """Send a message to the remote and register the given message handler.""" for msg_type in msg_types: self._message_handlers.setdefault(msg_type, []).append(on_message) try: self.send_message(send_msg) except (asyncio.CancelledError, Exception): for msg_type in msg_types: self._message_handlers[msg_type].remove(on_message) raise async def send_message_await_response_complex( self, send_msg: message.Message, do_append: Callable[[message.Message], bool], do_stop: Callable[[message.Message], bool], msg_types: Iterable[Type[Any]], timeout: float = 10.0, ) -> List[message.Message]: """Send a message to the remote and build up a list response. :param send_msg: The message (request) to send. :param do_append: Predicate to check if a received message is part of the response. :param do_stop: Predicate to check if a received message is the stop response. :param timeout: The maximum amount of time to wait for the stop response. :raises TimeoutAPIError: if a timeout occured """ fut = asyncio.get_event_loop().create_future() responses = [] def on_message(resp: message.Message) -> None: if fut.done(): return if do_append(resp): responses.append(resp) if do_stop(resp): fut.set_result(responses) def on_read_exception(exc: Exception) -> None: if not fut.done(): new_exc = exc if not isinstance(exc, APIConnectionError): new_exc = ReadFailedAPIError("Read failed") new_exc.__cause__ = exc fut.set_exception(new_exc) for msg_type in msg_types: self._message_handlers.setdefault(msg_type, []).append(on_message) self._read_exception_handlers.append(on_read_exception) # We must not await without a finally or # the message could fail to be removed if the # the await is cancelled try: self.send_message(send_msg) async with async_timeout.timeout(timeout): await fut except asyncio.TimeoutError as err: raise TimeoutAPIError( f"Timeout waiting for response for {type(send_msg)} after {timeout}s" ) from err finally: for msg_type in msg_types: with suppress(ValueError): self._message_handlers[msg_type].remove(on_message) with suppress(ValueError): self._read_exception_handlers.remove(on_read_exception) return responses async def send_message_await_response( self, send_msg: message.Message, response_type: Any, timeout: float = 10.0 ) -> Any: res = await self.send_message_await_response_complex( send_msg, lambda msg: True, # we will only get responses of `response_type` lambda msg: True, # we will only get responses of `response_type` (response_type,), timeout=timeout, ) if len(res) != 1: raise APIConnectionError(f"Expected one result, got {len(res)}") return res[0] def _report_fatal_error(self, err: Exception) -> None: """Report a fatal error that occurred during an operation. This should only be called for errors that mean the connection can no longer be used. The connection will be closed, all exception handlers notified. This method does not log the error, the call site should do so. """ if not self._expected_disconnect and not self._fatal_exception: # Only log the first error _LOGGER.warning( "%s: Connection error occurred: %s", self.log_name, err or type(err), exc_info=not str(err), # Log the full stack on empty error string ) self._fatal_exception = err self._connection_state = ConnectionState.CLOSED for handler in self._read_exception_handlers[:]: handler(err) self._read_exception_handlers.clear() self._cleanup() def _process_packet(self, pkt: Packet) -> None: """Process a packet from the socket.""" msg_type_proto = pkt.type if msg_type_proto not in MESSAGE_TYPE_TO_PROTO: _LOGGER.debug("%s: Skipping message type %s", self.log_name, msg_type_proto) return msg = MESSAGE_TYPE_TO_PROTO[msg_type_proto]() try: # MergeFromString instead of ParseFromString since # ParseFromString will clear the message first and # the msg is already empty. msg.MergeFromString(pkt.data) except Exception as e: _LOGGER.info( "%s: Invalid protobuf message: type=%s data=%s: %s", self.log_name, pkt.type, pkt.data, e, exc_info=True, ) self._report_fatal_error( ProtocolAPIError( f"Invalid protobuf message: type={pkt.type} data={pkt.data!r}: {e}" ) ) raise msg_type = type(msg) _LOGGER.debug("%s: Got message of type %s: %s", self.log_name, msg_type, msg) for handler in self._message_handlers.get(msg_type, [])[:]: handler(msg) # Pre-check the message type to avoid awaiting # since most messages are not internal messages if msg_type not in INTERNAL_MESSAGE_TYPES: return if isinstance(msg, DisconnectRequest): self.send_message(DisconnectResponse()) self._connection_state = ConnectionState.CLOSED self._expected_disconnect = True self._cleanup() elif isinstance(msg, PingRequest): self.send_message(PingResponse()) elif isinstance(msg, GetTimeRequest): resp = GetTimeResponse() resp.epoch_seconds = int(time.time()) self.send_message(resp) async def _ping(self) -> None: self._check_connected() await self.send_message_await_response(PingRequest(), PingResponse) async def disconnect(self) -> None: if not self._is_socket_open or not self._frame_helper: # We still want to send a disconnect request even # if the hello phase isn't finished to ensure we # the esp will clean up the connection as soon # as possible. return self._expected_disconnect = True try: await self.send_message_await_response( DisconnectRequest(), DisconnectResponse ) except APIConnectionError: pass self._connection_state = ConnectionState.CLOSED self._cleanup() async def force_disconnect(self) -> None: self._connection_state = ConnectionState.CLOSED self._expected_disconnect = True self._cleanup() @property def api_version(self) -> Optional[APIVersion]: return self._api_version