| """ |
| :mod:`websockets.exceptions` defines the following hierarchy of exceptions. |
| |
| * :exc:`WebSocketException` |
| * :exc:`ConnectionClosed` |
| * :exc:`ConnectionClosedOK` |
| * :exc:`ConnectionClosedError` |
| * :exc:`InvalidURI` |
| * :exc:`InvalidProxy` |
| * :exc:`InvalidHandshake` |
| * :exc:`SecurityError` |
| * :exc:`ProxyError` |
| * :exc:`InvalidProxyMessage` |
| * :exc:`InvalidProxyStatus` |
| * :exc:`InvalidMessage` |
| * :exc:`InvalidStatus` |
| * :exc:`InvalidStatusCode` (legacy) |
| * :exc:`InvalidHeader` |
| * :exc:`InvalidHeaderFormat` |
| * :exc:`InvalidHeaderValue` |
| * :exc:`InvalidOrigin` |
| * :exc:`InvalidUpgrade` |
| * :exc:`NegotiationError` |
| * :exc:`DuplicateParameter` |
| * :exc:`InvalidParameterName` |
| * :exc:`InvalidParameterValue` |
| * :exc:`AbortHandshake` (legacy) |
| * :exc:`RedirectHandshake` (legacy) |
| * :exc:`ProtocolError` (Sans-I/O) |
| * :exc:`PayloadTooBig` (Sans-I/O) |
| * :exc:`InvalidState` (Sans-I/O) |
| * :exc:`ConcurrencyError` |
| |
| """ |
|
|
| from __future__ import annotations |
|
|
| import warnings |
|
|
| from .imports import lazy_import |
|
|
|
|
| __all__ = [ |
| "WebSocketException", |
| "ConnectionClosed", |
| "ConnectionClosedOK", |
| "ConnectionClosedError", |
| "InvalidURI", |
| "InvalidProxy", |
| "InvalidHandshake", |
| "SecurityError", |
| "ProxyError", |
| "InvalidProxyMessage", |
| "InvalidProxyStatus", |
| "InvalidMessage", |
| "InvalidStatus", |
| "InvalidHeader", |
| "InvalidHeaderFormat", |
| "InvalidHeaderValue", |
| "InvalidOrigin", |
| "InvalidUpgrade", |
| "NegotiationError", |
| "DuplicateParameter", |
| "InvalidParameterName", |
| "InvalidParameterValue", |
| "ProtocolError", |
| "PayloadTooBig", |
| "InvalidState", |
| "ConcurrencyError", |
| ] |
|
|
|
|
| class WebSocketException(Exception): |
| """ |
| Base class for all exceptions defined by websockets. |
| |
| """ |
|
|
|
|
| class ConnectionClosed(WebSocketException): |
| """ |
| Raised when trying to interact with a closed connection. |
| |
| Attributes: |
| rcvd: If a close frame was received, its code and reason are available |
| in ``rcvd.code`` and ``rcvd.reason``. |
| sent: If a close frame was sent, its code and reason are available |
| in ``sent.code`` and ``sent.reason``. |
| rcvd_then_sent: If close frames were received and sent, this attribute |
| tells in which order this happened, from the perspective of this |
| side of the connection. |
| |
| """ |
|
|
| def __init__( |
| self, |
| rcvd: frames.Close | None, |
| sent: frames.Close | None, |
| rcvd_then_sent: bool | None = None, |
| ) -> None: |
| self.rcvd = rcvd |
| self.sent = sent |
| self.rcvd_then_sent = rcvd_then_sent |
| assert (self.rcvd_then_sent is None) == (self.rcvd is None or self.sent is None) |
|
|
| def __str__(self) -> str: |
| if self.rcvd is None: |
| if self.sent is None: |
| return "no close frame received or sent" |
| else: |
| return f"sent {self.sent}; no close frame received" |
| else: |
| if self.sent is None: |
| return f"received {self.rcvd}; no close frame sent" |
| else: |
| if self.rcvd_then_sent: |
| return f"received {self.rcvd}; then sent {self.sent}" |
| else: |
| return f"sent {self.sent}; then received {self.rcvd}" |
|
|
| |
|
|
| @property |
| def code(self) -> int: |
| warnings.warn( |
| "ConnectionClosed.code is deprecated; " |
| "use Protocol.close_code or ConnectionClosed.rcvd.code", |
| DeprecationWarning, |
| ) |
| if self.rcvd is None: |
| return frames.CloseCode.ABNORMAL_CLOSURE |
| return self.rcvd.code |
|
|
| @property |
| def reason(self) -> str: |
| warnings.warn( |
| "ConnectionClosed.reason is deprecated; " |
| "use Protocol.close_reason or ConnectionClosed.rcvd.reason", |
| DeprecationWarning, |
| ) |
| if self.rcvd is None: |
| return "" |
| return self.rcvd.reason |
|
|
|
|
| class ConnectionClosedOK(ConnectionClosed): |
| """ |
| Like :exc:`ConnectionClosed`, when the connection terminated properly. |
| |
| A close code with code 1000 (OK) or 1001 (going away) or without a code was |
| received and sent. |
| |
| """ |
|
|
|
|
| class ConnectionClosedError(ConnectionClosed): |
| """ |
| Like :exc:`ConnectionClosed`, when the connection terminated with an error. |
| |
| A close frame with a code other than 1000 (OK) or 1001 (going away) was |
| received or sent, or the closing handshake didn't complete properly. |
| |
| """ |
|
|
|
|
| class InvalidURI(WebSocketException): |
| """ |
| Raised when connecting to a URI that isn't a valid WebSocket URI. |
| |
| """ |
|
|
| def __init__(self, uri: str, msg: str) -> None: |
| self.uri = uri |
| self.msg = msg |
|
|
| def __str__(self) -> str: |
| return f"{self.uri} isn't a valid URI: {self.msg}" |
|
|
|
|
| class InvalidProxy(WebSocketException): |
| """ |
| Raised when connecting via a proxy that isn't valid. |
| |
| """ |
|
|
| def __init__(self, proxy: str, msg: str) -> None: |
| self.proxy = proxy |
| self.msg = msg |
|
|
| def __str__(self) -> str: |
| return f"{self.proxy} isn't a valid proxy: {self.msg}" |
|
|
|
|
| class InvalidHandshake(WebSocketException): |
| """ |
| Base class for exceptions raised when the opening handshake fails. |
| |
| """ |
|
|
|
|
| class SecurityError(InvalidHandshake): |
| """ |
| Raised when a handshake request or response breaks a security rule. |
| |
| Security limits can be configured with :doc:`environment variables |
| <../reference/variables>`. |
| |
| """ |
|
|
|
|
| class ProxyError(InvalidHandshake): |
| """ |
| Raised when failing to connect to a proxy. |
| |
| """ |
|
|
|
|
| class InvalidProxyMessage(ProxyError): |
| """ |
| Raised when an HTTP proxy response is malformed. |
| |
| """ |
|
|
|
|
| class InvalidProxyStatus(ProxyError): |
| """ |
| Raised when an HTTP proxy rejects the connection. |
| |
| """ |
|
|
| def __init__(self, response: http11.Response) -> None: |
| self.response = response |
|
|
| def __str__(self) -> str: |
| return f"proxy rejected connection: HTTP {self.response.status_code:d}" |
|
|
|
|
| class InvalidMessage(InvalidHandshake): |
| """ |
| Raised when a handshake request or response is malformed. |
| |
| """ |
|
|
|
|
| class InvalidStatus(InvalidHandshake): |
| """ |
| Raised when a handshake response rejects the WebSocket upgrade. |
| |
| """ |
|
|
| def __init__(self, response: http11.Response) -> None: |
| self.response = response |
|
|
| def __str__(self) -> str: |
| return ( |
| f"server rejected WebSocket connection: HTTP {self.response.status_code:d}" |
| ) |
|
|
|
|
| class InvalidHeader(InvalidHandshake): |
| """ |
| Raised when an HTTP header doesn't have a valid format or value. |
| |
| """ |
|
|
| def __init__(self, name: str, value: str | None = None) -> None: |
| self.name = name |
| self.value = value |
|
|
| def __str__(self) -> str: |
| if self.value is None: |
| return f"missing {self.name} header" |
| elif self.value == "": |
| return f"empty {self.name} header" |
| else: |
| return f"invalid {self.name} header: {self.value}" |
|
|
|
|
| class InvalidHeaderFormat(InvalidHeader): |
| """ |
| Raised when an HTTP header cannot be parsed. |
| |
| The format of the header doesn't match the grammar for that header. |
| |
| """ |
|
|
| def __init__(self, name: str, error: str, header: str, pos: int) -> None: |
| super().__init__(name, f"{error} at {pos} in {header}") |
|
|
|
|
| class InvalidHeaderValue(InvalidHeader): |
| """ |
| Raised when an HTTP header has a wrong value. |
| |
| The format of the header is correct but the value isn't acceptable. |
| |
| """ |
|
|
|
|
| class InvalidOrigin(InvalidHeader): |
| """ |
| Raised when the Origin header in a request isn't allowed. |
| |
| """ |
|
|
| def __init__(self, origin: str | None) -> None: |
| super().__init__("Origin", origin) |
|
|
|
|
| class InvalidUpgrade(InvalidHeader): |
| """ |
| Raised when the Upgrade or Connection header isn't correct. |
| |
| """ |
|
|
|
|
| class NegotiationError(InvalidHandshake): |
| """ |
| Raised when negotiating an extension or a subprotocol fails. |
| |
| """ |
|
|
|
|
| class DuplicateParameter(NegotiationError): |
| """ |
| Raised when a parameter name is repeated in an extension header. |
| |
| """ |
|
|
| def __init__(self, name: str) -> None: |
| self.name = name |
|
|
| def __str__(self) -> str: |
| return f"duplicate parameter: {self.name}" |
|
|
|
|
| class InvalidParameterName(NegotiationError): |
| """ |
| Raised when a parameter name in an extension header is invalid. |
| |
| """ |
|
|
| def __init__(self, name: str) -> None: |
| self.name = name |
|
|
| def __str__(self) -> str: |
| return f"invalid parameter name: {self.name}" |
|
|
|
|
| class InvalidParameterValue(NegotiationError): |
| """ |
| Raised when a parameter value in an extension header is invalid. |
| |
| """ |
|
|
| def __init__(self, name: str, value: str | None) -> None: |
| self.name = name |
| self.value = value |
|
|
| def __str__(self) -> str: |
| if self.value is None: |
| return f"missing value for parameter {self.name}" |
| elif self.value == "": |
| return f"empty value for parameter {self.name}" |
| else: |
| return f"invalid value for parameter {self.name}: {self.value}" |
|
|
|
|
| class ProtocolError(WebSocketException): |
| """ |
| Raised when receiving or sending a frame that breaks the protocol. |
| |
| The Sans-I/O implementation raises this exception when: |
| |
| * receiving or sending a frame that contains invalid data; |
| * receiving or sending an invalid sequence of frames. |
| |
| """ |
|
|
|
|
| class PayloadTooBig(WebSocketException): |
| """ |
| Raised when parsing a frame with a payload that exceeds the maximum size. |
| |
| The Sans-I/O layer uses this exception internally. It doesn't bubble up to |
| the I/O layer. |
| |
| The :meth:`~websockets.extensions.Extension.decode` method of extensions |
| must raise :exc:`PayloadTooBig` if decoding a frame would exceed the limit. |
| |
| """ |
|
|
| def __init__( |
| self, |
| size_or_message: int | None | str, |
| max_size: int | None = None, |
| current_size: int | None = None, |
| ) -> None: |
| if isinstance(size_or_message, str): |
| assert max_size is None |
| assert current_size is None |
| warnings.warn( |
| "PayloadTooBig(message) is deprecated; " |
| "change to PayloadTooBig(size, max_size)", |
| DeprecationWarning, |
| ) |
| self.message: str | None = size_or_message |
| else: |
| self.message = None |
| self.size: int | None = size_or_message |
| assert max_size is not None |
| self.max_size: int = max_size |
| self.current_size: int | None = None |
| self.set_current_size(current_size) |
|
|
| def __str__(self) -> str: |
| if self.message is not None: |
| return self.message |
| else: |
| message = "frame " |
| if self.size is not None: |
| message += f"with {self.size} bytes " |
| if self.current_size is not None: |
| message += f"after reading {self.current_size} bytes " |
| message += f"exceeds limit of {self.max_size} bytes" |
| return message |
|
|
| def set_current_size(self, current_size: int | None) -> None: |
| assert self.current_size is None |
| if current_size is not None: |
| self.max_size += current_size |
| self.current_size = current_size |
|
|
|
|
| class InvalidState(WebSocketException, AssertionError): |
| """ |
| Raised when sending a frame is forbidden in the current state. |
| |
| Specifically, the Sans-I/O layer raises this exception when: |
| |
| * sending a data frame to a connection in a state other |
| :attr:`~websockets.protocol.State.OPEN`; |
| * sending a control frame to a connection in a state other than |
| :attr:`~websockets.protocol.State.OPEN` or |
| :attr:`~websockets.protocol.State.CLOSING`. |
| |
| """ |
|
|
|
|
| class ConcurrencyError(WebSocketException, RuntimeError): |
| """ |
| Raised when receiving or sending messages concurrently. |
| |
| WebSocket is a connection-oriented protocol. Reads must be serialized; so |
| must be writes. However, reading and writing concurrently is possible. |
| |
| """ |
|
|
|
|
| |
| from . import frames, http11 |
|
|
|
|
| lazy_import( |
| globals(), |
| deprecated_aliases={ |
| |
| "AbortHandshake": ".legacy.exceptions", |
| "InvalidStatusCode": ".legacy.exceptions", |
| "RedirectHandshake": ".legacy.exceptions", |
| "WebSocketProtocolError": ".legacy.exceptions", |
| }, |
| ) |
|
|
