|
- from __future__ import annotations
-
- import socket
- import ssl as ssl_module
- import threading
- import warnings
- from collections.abc import Sequence
- from typing import Any, Callable, Literal, TypeVar, cast
-
- from ..client import ClientProtocol
- from ..datastructures import Headers, HeadersLike
- from ..exceptions import InvalidProxyMessage, InvalidProxyStatus, ProxyError
- from ..extensions.base import ClientExtensionFactory
- from ..extensions.permessage_deflate import enable_client_permessage_deflate
- from ..headers import build_authorization_basic, build_host, validate_subprotocols
- from ..http11 import USER_AGENT, Response
- from ..protocol import CONNECTING, Event
- from ..streams import StreamReader
- from ..typing import LoggerLike, Origin, Subprotocol
- from ..uri import Proxy, WebSocketURI, get_proxy, parse_proxy, parse_uri
- from .connection import Connection
- from .utils import Deadline
-
-
- __all__ = ["connect", "unix_connect", "ClientConnection"]
-
-
- class ClientConnection(Connection):
- """
- :mod:`threading` implementation of a WebSocket client connection.
-
- :class:`ClientConnection` provides :meth:`recv` and :meth:`send` methods for
- receiving and sending messages.
-
- It supports iteration to receive messages::
-
- for message in websocket:
- process(message)
-
- The iterator exits normally when the connection is closed with close code
- 1000 (OK) or 1001 (going away) or without a close code. It raises a
- :exc:`~websockets.exceptions.ConnectionClosedError` when the connection is
- closed with any other code.
-
- The ``ping_interval``, ``ping_timeout``, ``close_timeout``, and
- ``max_queue`` arguments have the same meaning as in :func:`connect`.
-
- Args:
- socket: Socket connected to a WebSocket server.
- protocol: Sans-I/O connection.
-
- """
-
- def __init__(
- self,
- socket: socket.socket,
- protocol: ClientProtocol,
- *,
- ping_interval: float | None = 20,
- ping_timeout: float | None = 20,
- close_timeout: float | None = 10,
- max_queue: int | None | tuple[int | None, int | None] = 16,
- ) -> None:
- self.protocol: ClientProtocol
- self.response_rcvd = threading.Event()
- super().__init__(
- socket,
- protocol,
- ping_interval=ping_interval,
- ping_timeout=ping_timeout,
- close_timeout=close_timeout,
- max_queue=max_queue,
- )
-
- def handshake(
- self,
- additional_headers: HeadersLike | None = None,
- user_agent_header: str | None = USER_AGENT,
- timeout: float | None = None,
- ) -> None:
- """
- Perform the opening handshake.
-
- """
- with self.send_context(expected_state=CONNECTING):
- self.request = self.protocol.connect()
- if additional_headers is not None:
- self.request.headers.update(additional_headers)
- if user_agent_header is not None:
- self.request.headers.setdefault("User-Agent", user_agent_header)
- self.protocol.send_request(self.request)
-
- if not self.response_rcvd.wait(timeout):
- raise TimeoutError("timed out while waiting for handshake response")
-
- # self.protocol.handshake_exc is set when the connection is lost before
- # receiving a response, when the response cannot be parsed, or when the
- # response fails the handshake.
-
- if self.protocol.handshake_exc is not None:
- raise self.protocol.handshake_exc
-
- def process_event(self, event: Event) -> None:
- """
- Process one incoming event.
-
- """
- # First event - handshake response.
- if self.response is None:
- assert isinstance(event, Response)
- self.response = event
- self.response_rcvd.set()
- # Later events - frames.
- else:
- super().process_event(event)
-
- def recv_events(self) -> None:
- """
- Read incoming data from the socket and process events.
-
- """
- try:
- super().recv_events()
- finally:
- # If the connection is closed during the handshake, unblock it.
- self.response_rcvd.set()
-
-
- def connect(
- uri: str,
- *,
- # TCP/TLS
- sock: socket.socket | None = None,
- ssl: ssl_module.SSLContext | None = None,
- server_hostname: str | None = None,
- # WebSocket
- origin: Origin | None = None,
- extensions: Sequence[ClientExtensionFactory] | None = None,
- subprotocols: Sequence[Subprotocol] | None = None,
- compression: str | None = "deflate",
- # HTTP
- additional_headers: HeadersLike | None = None,
- user_agent_header: str | None = USER_AGENT,
- proxy: str | Literal[True] | None = True,
- proxy_ssl: ssl_module.SSLContext | None = None,
- proxy_server_hostname: str | None = None,
- # Timeouts
- open_timeout: float | None = 10,
- ping_interval: float | None = 20,
- ping_timeout: float | None = 20,
- close_timeout: float | None = 10,
- # Limits
- max_size: int | None = 2**20,
- max_queue: int | None | tuple[int | None, int | None] = 16,
- # Logging
- logger: LoggerLike | None = None,
- # Escape hatch for advanced customization
- create_connection: type[ClientConnection] | None = None,
- **kwargs: Any,
- ) -> ClientConnection:
- """
- Connect to the WebSocket server at ``uri``.
-
- This function returns a :class:`ClientConnection` instance, which you can
- use to send and receive messages.
-
- :func:`connect` may be used as a context manager::
-
- from websockets.sync.client import connect
-
- with connect(...) as websocket:
- ...
-
- The connection is closed automatically when exiting the context.
-
- Args:
- uri: URI of the WebSocket server.
- sock: Preexisting TCP socket. ``sock`` overrides the host and port
- from ``uri``. You may call :func:`socket.create_connection` to
- create a suitable TCP socket.
- ssl: Configuration for enabling TLS on the connection.
- server_hostname: Host name for the TLS handshake. ``server_hostname``
- overrides the host name from ``uri``.
- origin: Value of the ``Origin`` header, for servers that require it.
- extensions: List of supported extensions, in order in which they
- should be negotiated and run.
- subprotocols: List of supported subprotocols, in order of decreasing
- preference.
- compression: The "permessage-deflate" extension is enabled by default.
- Set ``compression`` to :obj:`None` to disable it. See the
- :doc:`compression guide <../../topics/compression>` for details.
- additional_headers (HeadersLike | None): Arbitrary HTTP headers to add
- to the handshake request.
- user_agent_header: Value of the ``User-Agent`` request header.
- It defaults to ``"Python/x.y.z websockets/X.Y"``.
- Setting it to :obj:`None` removes the header.
- proxy: If a proxy is configured, it is used by default. Set ``proxy``
- to :obj:`None` to disable the proxy or to the address of a proxy
- to override the system configuration. See the :doc:`proxy docs
- <../../topics/proxies>` for details.
- proxy_ssl: Configuration for enabling TLS on the proxy connection.
- proxy_server_hostname: Host name for the TLS handshake with the proxy.
- ``proxy_server_hostname`` overrides the host name from ``proxy``.
- open_timeout: Timeout for opening the connection in seconds.
- :obj:`None` disables the timeout.
- ping_interval: Interval between keepalive pings in seconds.
- :obj:`None` disables keepalive.
- ping_timeout: Timeout for keepalive pings in seconds.
- :obj:`None` disables timeouts.
- close_timeout: Timeout for closing the connection in seconds.
- :obj:`None` disables the timeout.
- max_size: Maximum size of incoming messages in bytes.
- :obj:`None` disables the limit.
- max_queue: High-water mark of the buffer where frames are received.
- It defaults to 16 frames. The low-water mark defaults to ``max_queue
- // 4``. You may pass a ``(high, low)`` tuple to set the high-water
- and low-water marks. If you want to disable flow control entirely,
- you may set it to ``None``, although that's a bad idea.
- logger: Logger for this client.
- It defaults to ``logging.getLogger("websockets.client")``.
- See the :doc:`logging guide <../../topics/logging>` for details.
- create_connection: Factory for the :class:`ClientConnection` managing
- the connection. Set it to a wrapper or a subclass to customize
- connection handling.
-
- Any other keyword arguments are passed to :func:`~socket.create_connection`.
-
- Raises:
- InvalidURI: If ``uri`` isn't a valid WebSocket URI.
- OSError: If the TCP connection fails.
- InvalidHandshake: If the opening handshake fails.
- TimeoutError: If the opening handshake times out.
-
- """
-
- # Process parameters
-
- # Backwards compatibility: ssl used to be called ssl_context.
- if ssl is None and "ssl_context" in kwargs:
- ssl = kwargs.pop("ssl_context")
- warnings.warn( # deprecated in 13.0 - 2024-08-20
- "ssl_context was renamed to ssl",
- DeprecationWarning,
- )
-
- ws_uri = parse_uri(uri)
- if not ws_uri.secure and ssl is not None:
- raise ValueError("ssl argument is incompatible with a ws:// URI")
-
- # Private APIs for unix_connect()
- unix: bool = kwargs.pop("unix", False)
- path: str | None = kwargs.pop("path", None)
-
- if unix:
- if path is None and sock is None:
- raise ValueError("missing path argument")
- elif path is not None and sock is not None:
- raise ValueError("path and sock arguments are incompatible")
-
- if subprotocols is not None:
- validate_subprotocols(subprotocols)
-
- if compression == "deflate":
- extensions = enable_client_permessage_deflate(extensions)
- elif compression is not None:
- raise ValueError(f"unsupported compression: {compression}")
-
- if unix:
- proxy = None
- if sock is not None:
- proxy = None
- if proxy is True:
- proxy = get_proxy(ws_uri)
-
- # Calculate timeouts on the TCP, TLS, and WebSocket handshakes.
- # The TCP and TLS timeouts must be set on the socket, then removed
- # to avoid conflicting with the WebSocket timeout in handshake().
- deadline = Deadline(open_timeout)
-
- if create_connection is None:
- create_connection = ClientConnection
-
- try:
- # Connect socket
-
- if sock is None:
- if unix:
- sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
- sock.settimeout(deadline.timeout())
- assert path is not None # mypy cannot figure this out
- sock.connect(path)
- elif proxy is not None:
- proxy_parsed = parse_proxy(proxy)
- if proxy_parsed.scheme[:5] == "socks":
- # Connect to the server through the proxy.
- sock = connect_socks_proxy(
- proxy_parsed,
- ws_uri,
- deadline,
- # websockets is consistent with the socket module while
- # python_socks is consistent across implementations.
- local_addr=kwargs.pop("source_address", None),
- )
- elif proxy_parsed.scheme[:4] == "http":
- # Validate the proxy_ssl argument.
- if proxy_parsed.scheme != "https" and proxy_ssl is not None:
- raise ValueError(
- "proxy_ssl argument is incompatible with an http:// proxy"
- )
- # Connect to the server through the proxy.
- sock = connect_http_proxy(
- proxy_parsed,
- ws_uri,
- deadline,
- user_agent_header=user_agent_header,
- ssl=proxy_ssl,
- server_hostname=proxy_server_hostname,
- **kwargs,
- )
- else:
- raise AssertionError("unsupported proxy")
- else:
- kwargs.setdefault("timeout", deadline.timeout())
- sock = socket.create_connection(
- (ws_uri.host, ws_uri.port),
- **kwargs,
- )
- sock.settimeout(None)
-
- # Disable Nagle algorithm
-
- if not unix:
- sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, True)
-
- # Initialize TLS wrapper and perform TLS handshake
-
- if ws_uri.secure:
- if ssl is None:
- ssl = ssl_module.create_default_context()
- if server_hostname is None:
- server_hostname = ws_uri.host
- sock.settimeout(deadline.timeout())
- if proxy_ssl is None:
- sock = ssl.wrap_socket(sock, server_hostname=server_hostname)
- else:
- sock_2 = SSLSSLSocket(sock, ssl, server_hostname=server_hostname)
- # Let's pretend that sock is a socket, even though it isn't.
- sock = cast(socket.socket, sock_2)
- sock.settimeout(None)
-
- # Initialize WebSocket protocol
-
- protocol = ClientProtocol(
- ws_uri,
- origin=origin,
- extensions=extensions,
- subprotocols=subprotocols,
- max_size=max_size,
- logger=logger,
- )
-
- # Initialize WebSocket connection
-
- connection = create_connection(
- sock,
- protocol,
- ping_interval=ping_interval,
- ping_timeout=ping_timeout,
- close_timeout=close_timeout,
- max_queue=max_queue,
- )
- except Exception:
- if sock is not None:
- sock.close()
- raise
-
- try:
- connection.handshake(
- additional_headers,
- user_agent_header,
- deadline.timeout(),
- )
- except Exception:
- connection.close_socket()
- connection.recv_events_thread.join()
- raise
-
- connection.start_keepalive()
- return connection
-
-
- def unix_connect(
- path: str | None = None,
- uri: str | None = None,
- **kwargs: Any,
- ) -> ClientConnection:
- """
- Connect to a WebSocket server listening on a Unix socket.
-
- This function accepts the same keyword arguments as :func:`connect`.
-
- It's only available on Unix.
-
- It's mainly useful for debugging servers listening on Unix sockets.
-
- Args:
- path: File system path to the Unix socket.
- uri: URI of the WebSocket server. ``uri`` defaults to
- ``ws://localhost/`` or, when a ``ssl`` is provided, to
- ``wss://localhost/``.
-
- """
- if uri is None:
- # Backwards compatibility: ssl used to be called ssl_context.
- if kwargs.get("ssl") is None and kwargs.get("ssl_context") is None:
- uri = "ws://localhost/"
- else:
- uri = "wss://localhost/"
- return connect(uri=uri, unix=True, path=path, **kwargs)
-
-
- try:
- from python_socks import ProxyType
- from python_socks.sync import Proxy as SocksProxy
-
- SOCKS_PROXY_TYPES = {
- "socks5h": ProxyType.SOCKS5,
- "socks5": ProxyType.SOCKS5,
- "socks4a": ProxyType.SOCKS4,
- "socks4": ProxyType.SOCKS4,
- }
-
- SOCKS_PROXY_RDNS = {
- "socks5h": True,
- "socks5": False,
- "socks4a": True,
- "socks4": False,
- }
-
- def connect_socks_proxy(
- proxy: Proxy,
- ws_uri: WebSocketURI,
- deadline: Deadline,
- **kwargs: Any,
- ) -> socket.socket:
- """Connect via a SOCKS proxy and return the socket."""
- socks_proxy = SocksProxy(
- SOCKS_PROXY_TYPES[proxy.scheme],
- proxy.host,
- proxy.port,
- proxy.username,
- proxy.password,
- SOCKS_PROXY_RDNS[proxy.scheme],
- )
- kwargs.setdefault("timeout", deadline.timeout())
- # connect() is documented to raise OSError and TimeoutError.
- # Wrap other exceptions in ProxyError, a subclass of InvalidHandshake.
- try:
- return socks_proxy.connect(ws_uri.host, ws_uri.port, **kwargs)
- except (OSError, TimeoutError, socket.timeout):
- raise
- except Exception as exc:
- raise ProxyError("failed to connect to SOCKS proxy") from exc
-
- except ImportError:
-
- def connect_socks_proxy(
- proxy: Proxy,
- ws_uri: WebSocketURI,
- deadline: Deadline,
- **kwargs: Any,
- ) -> socket.socket:
- raise ImportError("python-socks is required to use a SOCKS proxy")
-
-
- def prepare_connect_request(
- proxy: Proxy,
- ws_uri: WebSocketURI,
- user_agent_header: str | None = None,
- ) -> bytes:
- host = build_host(ws_uri.host, ws_uri.port, ws_uri.secure, always_include_port=True)
- headers = Headers()
- headers["Host"] = build_host(ws_uri.host, ws_uri.port, ws_uri.secure)
- if user_agent_header is not None:
- headers["User-Agent"] = user_agent_header
- if proxy.username is not None:
- assert proxy.password is not None # enforced by parse_proxy()
- headers["Proxy-Authorization"] = build_authorization_basic(
- proxy.username, proxy.password
- )
- # We cannot use the Request class because it supports only GET requests.
- return f"CONNECT {host} HTTP/1.1\r\n".encode() + headers.serialize()
-
-
- def read_connect_response(sock: socket.socket, deadline: Deadline) -> Response:
- reader = StreamReader()
- parser = Response.parse(
- reader.read_line,
- reader.read_exact,
- reader.read_to_eof,
- include_body=False,
- )
- try:
- while True:
- sock.settimeout(deadline.timeout())
- data = sock.recv(4096)
- if data:
- reader.feed_data(data)
- else:
- reader.feed_eof()
- next(parser)
- except StopIteration as exc:
- assert isinstance(exc.value, Response) # help mypy
- response = exc.value
- if 200 <= response.status_code < 300:
- return response
- else:
- raise InvalidProxyStatus(response)
- except socket.timeout:
- raise TimeoutError("timed out while connecting to HTTP proxy")
- except Exception as exc:
- raise InvalidProxyMessage(
- "did not receive a valid HTTP response from proxy"
- ) from exc
- finally:
- sock.settimeout(None)
-
-
- def connect_http_proxy(
- proxy: Proxy,
- ws_uri: WebSocketURI,
- deadline: Deadline,
- *,
- user_agent_header: str | None = None,
- ssl: ssl_module.SSLContext | None = None,
- server_hostname: str | None = None,
- **kwargs: Any,
- ) -> socket.socket:
- # Connect socket
-
- kwargs.setdefault("timeout", deadline.timeout())
- sock = socket.create_connection((proxy.host, proxy.port), **kwargs)
-
- # Initialize TLS wrapper and perform TLS handshake
-
- if proxy.scheme == "https":
- if ssl is None:
- ssl = ssl_module.create_default_context()
- if server_hostname is None:
- server_hostname = proxy.host
- sock.settimeout(deadline.timeout())
- sock = ssl.wrap_socket(sock, server_hostname=server_hostname)
- sock.settimeout(None)
-
- # Send CONNECT request to the proxy and read response.
-
- sock.sendall(prepare_connect_request(proxy, ws_uri, user_agent_header))
- try:
- read_connect_response(sock, deadline)
- except Exception:
- sock.close()
- raise
-
- return sock
-
-
- T = TypeVar("T")
- F = TypeVar("F", bound=Callable[..., T])
-
-
- class SSLSSLSocket:
- """
- Socket-like object providing TLS-in-TLS.
-
- Only methods that are used by websockets are implemented.
-
- """
-
- recv_bufsize = 65536
-
- def __init__(
- self,
- sock: socket.socket,
- ssl_context: ssl_module.SSLContext,
- server_hostname: str | None = None,
- ) -> None:
- self.incoming = ssl_module.MemoryBIO()
- self.outgoing = ssl_module.MemoryBIO()
- self.ssl_socket = sock
- self.ssl_object = ssl_context.wrap_bio(
- self.incoming,
- self.outgoing,
- server_hostname=server_hostname,
- )
- self.run_io(self.ssl_object.do_handshake)
-
- def run_io(self, func: Callable[..., T], *args: Any) -> T:
- while True:
- want_read = False
- want_write = False
- try:
- result = func(*args)
- except ssl_module.SSLWantReadError:
- want_read = True
- except ssl_module.SSLWantWriteError: # pragma: no cover
- want_write = True
-
- # Write outgoing data in all cases.
- data = self.outgoing.read()
- if data:
- self.ssl_socket.sendall(data)
-
- # Read incoming data and retry on SSLWantReadError.
- if want_read:
- data = self.ssl_socket.recv(self.recv_bufsize)
- if data:
- self.incoming.write(data)
- else:
- self.incoming.write_eof()
- continue
- # Retry after writing outgoing data on SSLWantWriteError.
- if want_write: # pragma: no cover
- continue
- # Return result if no error happened.
- return result
-
- def recv(self, buflen: int) -> bytes:
- try:
- return self.run_io(self.ssl_object.read, buflen)
- except ssl_module.SSLEOFError:
- return b"" # always ignore ragged EOFs
-
- def send(self, data: bytes) -> int:
- return self.run_io(self.ssl_object.write, data)
-
- def sendall(self, data: bytes) -> None:
- # adapted from ssl_module.SSLSocket.sendall()
- count = 0
- with memoryview(data) as view, view.cast("B") as byte_view:
- amount = len(byte_view)
- while count < amount:
- count += self.send(byte_view[count:])
-
- # recv_into(), recvfrom(), recvfrom_into(), sendto(), unwrap(), and the
- # flags argument aren't implemented because websockets doesn't need them.
-
- def __getattr__(self, name: str) -> Any:
- return getattr(self.ssl_socket, name)
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