second commit

env/lib/python3.11/site-packages/websockets/client.py

@@ -0,0 +1,400 @@
+from __future__ import annotations
+
+import os
+import random
+import warnings
+from collections.abc import Generator, Sequence
+from typing import Any
+
+from .datastructures import Headers, MultipleValuesError
+from .exceptions import (
+    InvalidHandshake,
+    InvalidHeader,
+    InvalidHeaderValue,
+    InvalidStatus,
+    InvalidUpgrade,
+    NegotiationError,
+)
+from .extensions import ClientExtensionFactory, Extension
+from .headers import (
+    build_authorization_basic,
+    build_extension,
+    build_host,
+    build_subprotocol,
+    parse_connection,
+    parse_extension,
+    parse_subprotocol,
+    parse_upgrade,
+)
+from .http11 import Request, Response
+from .imports import lazy_import
+from .protocol import CLIENT, CONNECTING, OPEN, Protocol, State
+from .typing import (
+    ConnectionOption,
+    ExtensionHeader,
+    LoggerLike,
+    Origin,
+    Subprotocol,
+    UpgradeProtocol,
+)
+from .uri import WebSocketURI
+from .utils import accept_key, generate_key
+
+
+__all__ = ["ClientProtocol"]
+
+
+class ClientProtocol(Protocol):
+    """
+    Sans-I/O implementation of a WebSocket client connection.
+
+    Args:
+        wsuri: URI of the WebSocket server, parsed
+            with :func:`~websockets.uri.parse_uri`.
+        origin: Value of the ``Origin`` header. This is useful when connecting
+            to a server that validates the ``Origin`` header to defend against
+            Cross-Site WebSocket Hijacking attacks.
+        extensions: List of supported extensions, in order in which they
+            should be tried.
+        subprotocols: List of supported subprotocols, in order of decreasing
+            preference.
+        state: Initial state of the WebSocket connection.
+        max_size: Maximum size of incoming messages in bytes;
+            :obj:`None` disables the limit.
+        logger: Logger for this connection;
+            defaults to ``logging.getLogger("websockets.client")``;
+            see the :doc:`logging guide <../../topics/logging>` for details.
+
+    """
+
+    def __init__(
+        self,
+        wsuri: WebSocketURI,
+        *,
+        origin: Origin | None = None,
+        extensions: Sequence[ClientExtensionFactory] | None = None,
+        subprotocols: Sequence[Subprotocol] | None = None,
+        state: State = CONNECTING,
+        max_size: int | None = 2**20,
+        logger: LoggerLike | None = None,
+    ) -> None:
+        super().__init__(
+            side=CLIENT,
+            state=state,
+            max_size=max_size,
+            logger=logger,
+        )
+        self.wsuri = wsuri
+        self.origin = origin
+        self.available_extensions = extensions
+        self.available_subprotocols = subprotocols
+        self.key = generate_key()
+
+    def connect(self) -> Request:
+        """
+        Create a handshake request to open a connection.
+
+        You must send the handshake request with :meth:`send_request`.
+
+        You can modify it before sending it, for example to add HTTP headers.
+
+        Returns:
+            WebSocket handshake request event to send to the server.
+
+        """
+        headers = Headers()
+
+        headers["Host"] = build_host(
+            self.wsuri.host, self.wsuri.port, self.wsuri.secure
+        )
+
+        if self.wsuri.user_info:
+            headers["Authorization"] = build_authorization_basic(*self.wsuri.user_info)
+
+        if self.origin is not None:
+            headers["Origin"] = self.origin
+
+        headers["Upgrade"] = "websocket"
+        headers["Connection"] = "Upgrade"
+        headers["Sec-WebSocket-Key"] = self.key
+        headers["Sec-WebSocket-Version"] = "13"
+
+        if self.available_extensions is not None:
+            extensions_header = build_extension(
+                [
+                    (extension_factory.name, extension_factory.get_request_params())
+                    for extension_factory in self.available_extensions
+                ]
+            )
+            headers["Sec-WebSocket-Extensions"] = extensions_header
+
+        if self.available_subprotocols is not None:
+            protocol_header = build_subprotocol(self.available_subprotocols)
+            headers["Sec-WebSocket-Protocol"] = protocol_header
+
+        return Request(self.wsuri.resource_name, headers)
+
+    def process_response(self, response: Response) -> None:
+        """
+        Check a handshake response.
+
+        Args:
+            request: WebSocket handshake response received from the server.
+
+        Raises:
+            InvalidHandshake: If the handshake response is invalid.
+
+        """
+
+        if response.status_code != 101:
+            raise InvalidStatus(response)
+
+        headers = response.headers
+
+        connection: list[ConnectionOption] = sum(
+            [parse_connection(value) for value in headers.get_all("Connection")], []
+        )
+
+        if not any(value.lower() == "upgrade" for value in connection):
+            raise InvalidUpgrade(
+                "Connection", ", ".join(connection) if connection else None
+            )
+
+        upgrade: list[UpgradeProtocol] = sum(
+            [parse_upgrade(value) for value in headers.get_all("Upgrade")], []
+        )
+
+        # For compatibility with non-strict implementations, ignore case when
+        # checking the Upgrade header. It's supposed to be 'WebSocket'.
+        if not (len(upgrade) == 1 and upgrade[0].lower() == "websocket"):
+            raise InvalidUpgrade("Upgrade", ", ".join(upgrade) if upgrade else None)
+
+        try:
+            s_w_accept = headers["Sec-WebSocket-Accept"]
+        except KeyError:
+            raise InvalidHeader("Sec-WebSocket-Accept") from None
+        except MultipleValuesError:
+            raise InvalidHeader("Sec-WebSocket-Accept", "multiple values") from None
+
+        if s_w_accept != accept_key(self.key):
+            raise InvalidHeaderValue("Sec-WebSocket-Accept", s_w_accept)
+
+        self.extensions = self.process_extensions(headers)
+
+        self.subprotocol = self.process_subprotocol(headers)
+
+    def process_extensions(self, headers: Headers) -> list[Extension]:
+        """
+        Handle the Sec-WebSocket-Extensions HTTP response header.
+
+        Check that each extension is supported, as well as its parameters.
+
+        :rfc:`6455` leaves the rules up to the specification of each
+        extension.
+
+        To provide this level of flexibility, for each extension accepted by
+        the server, we check for a match with each extension available in the
+        client configuration. If no match is found, an exception is raised.
+
+        If several variants of the same extension are accepted by the server,
+        it may be configured several times, which won't make sense in general.
+        Extensions must implement their own requirements. For this purpose,
+        the list of previously accepted extensions is provided.
+
+        Other requirements, for example related to mandatory extensions or the
+        order of extensions, may be implemented by overriding this method.
+
+        Args:
+            headers: WebSocket handshake response headers.
+
+        Returns:
+            List of accepted extensions.
+
+        Raises:
+            InvalidHandshake: To abort the handshake.
+
+        """
+        accepted_extensions: list[Extension] = []
+
+        extensions = headers.get_all("Sec-WebSocket-Extensions")
+
+        if extensions:
+            if self.available_extensions is None:
+                raise NegotiationError("no extensions supported")
+
+            parsed_extensions: list[ExtensionHeader] = sum(
+                [parse_extension(header_value) for header_value in extensions], []
+            )
+
+            for name, response_params in parsed_extensions:
+                for extension_factory in self.available_extensions:
+                    # Skip non-matching extensions based on their name.
+                    if extension_factory.name != name:
+                        continue
+
+                    # Skip non-matching extensions based on their params.
+                    try:
+                        extension = extension_factory.process_response_params(
+                            response_params, accepted_extensions
+                        )
+                    except NegotiationError:
+                        continue
+
+                    # Add matching extension to the final list.
+                    accepted_extensions.append(extension)
+
+                    # Break out of the loop once we have a match.
+                    break
+
+                # If we didn't break from the loop, no extension in our list
+                # matched what the server sent. Fail the connection.
+                else:
+                    raise NegotiationError(
+                        f"Unsupported extension: "
+                        f"name = {name}, params = {response_params}"
+                    )
+
+        return accepted_extensions
+
+    def process_subprotocol(self, headers: Headers) -> Subprotocol | None:
+        """
+        Handle the Sec-WebSocket-Protocol HTTP response header.
+
+        If provided, check that it contains exactly one supported subprotocol.
+
+        Args:
+            headers: WebSocket handshake response headers.
+
+        Returns:
+           Subprotocol, if one was selected.
+
+        """
+        subprotocol: Subprotocol | None = None
+
+        subprotocols = headers.get_all("Sec-WebSocket-Protocol")
+
+        if subprotocols:
+            if self.available_subprotocols is None:
+                raise NegotiationError("no subprotocols supported")
+
+            parsed_subprotocols: Sequence[Subprotocol] = sum(
+                [parse_subprotocol(header_value) for header_value in subprotocols], []
+            )
+
+            if len(parsed_subprotocols) > 1:
+                raise InvalidHeader(
+                    "Sec-WebSocket-Protocol",
+                    f"multiple values: {', '.join(parsed_subprotocols)}",
+                )
+
+            subprotocol = parsed_subprotocols[0]
+
+            if subprotocol not in self.available_subprotocols:
+                raise NegotiationError(f"unsupported subprotocol: {subprotocol}")
+
+        return subprotocol
+
+    def send_request(self, request: Request) -> None:
+        """
+        Send a handshake request to the server.
+
+        Args:
+            request: WebSocket handshake request event.
+
+        """
+        if self.debug:
+            self.logger.debug("> GET %s HTTP/1.1", request.path)
+            for key, value in request.headers.raw_items():
+                self.logger.debug("> %s: %s", key, value)
+
+        self.writes.append(request.serialize())
+
+    def parse(self) -> Generator[None]:
+        if self.state is CONNECTING:
+            try:
+                response = yield from Response.parse(
+                    self.reader.read_line,
+                    self.reader.read_exact,
+                    self.reader.read_to_eof,
+                )
+            except Exception as exc:
+                self.handshake_exc = exc
+                self.send_eof()
+                self.parser = self.discard()
+                next(self.parser)  # start coroutine
+                yield
+
+            if self.debug:
+                code, phrase = response.status_code, response.reason_phrase
+                self.logger.debug("< HTTP/1.1 %d %s", code, phrase)
+                for key, value in response.headers.raw_items():
+                    self.logger.debug("< %s: %s", key, value)
+                if response.body is not None:
+                    self.logger.debug("< [body] (%d bytes)", len(response.body))
+
+            try:
+                self.process_response(response)
+            except InvalidHandshake as exc:
+                response._exception = exc
+                self.events.append(response)
+                self.handshake_exc = exc
+                self.send_eof()
+                self.parser = self.discard()
+                next(self.parser)  # start coroutine
+                yield
+
+            assert self.state is CONNECTING
+            self.state = OPEN
+            self.events.append(response)
+
+        yield from super().parse()
+
+
+class ClientConnection(ClientProtocol):
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
+        warnings.warn(  # deprecated in 11.0 - 2023-04-02
+            "ClientConnection was renamed to ClientProtocol",
+            DeprecationWarning,
+        )
+        super().__init__(*args, **kwargs)
+
+
+BACKOFF_INITIAL_DELAY = float(os.environ.get("WEBSOCKETS_BACKOFF_INITIAL_DELAY", "5"))
+BACKOFF_MIN_DELAY = float(os.environ.get("WEBSOCKETS_BACKOFF_MIN_DELAY", "3.1"))
+BACKOFF_MAX_DELAY = float(os.environ.get("WEBSOCKETS_BACKOFF_MAX_DELAY", "90.0"))
+BACKOFF_FACTOR = float(os.environ.get("WEBSOCKETS_BACKOFF_FACTOR", "1.618"))
+
+
+def backoff(
+    initial_delay: float = BACKOFF_INITIAL_DELAY,
+    min_delay: float = BACKOFF_MIN_DELAY,
+    max_delay: float = BACKOFF_MAX_DELAY,
+    factor: float = BACKOFF_FACTOR,
+) -> Generator[float]:
+    """
+    Generate a series of backoff delays between reconnection attempts.
+
+    Yields:
+        How many seconds to wait before retrying to connect.
+
+    """
+    # Add a random initial delay between 0 and 5 seconds.
+    # See 7.2.3. Recovering from Abnormal Closure in RFC 6455.
+    yield random.random() * initial_delay
+    delay = min_delay
+    while delay < max_delay:
+        yield delay
+        delay *= factor
+    while True:
+        yield max_delay
+
+
+lazy_import(
+    globals(),
+    deprecated_aliases={
+        # deprecated in 14.0 - 2024-11-09
+        "WebSocketClientProtocol": ".legacy.client",
+        "connect": ".legacy.client",
+        "unix_connect": ".legacy.client",
+    },
+)