| | """ |
| | :mod:`websockets.exceptions` defines the following hierarchy of exceptions. |
| | |
| | * :exc:`WebSocketException` |
| | * :exc:`ConnectionClosed` |
| | * :exc:`ConnectionClosedOK` |
| | * :exc:`ConnectionClosedError` |
| | * :exc:`InvalidURI` |
| | * :exc:`InvalidHandshake` |
| | * :exc:`SecurityError` |
| | * :exc:`InvalidMessage` (legacy) |
| | * :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", |
| | "InvalidHandshake", |
| | "SecurityError", |
| | "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 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 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 ( |
| | "server rejected WebSocket connection: " |
| | f"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, |
| | cur_size: int | None = None, |
| | ) -> None: |
| | if isinstance(size_or_message, str): |
| | assert max_size is None |
| | assert cur_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.cur_size: int | None = None |
| | self.set_current_size(cur_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.cur_size is not None: |
| | message += f"after reading {self.cur_size} bytes " |
| | message += f"exceeds limit of {self.max_size} bytes" |
| | return message |
| |
|
| | def set_current_size(self, cur_size: int | None) -> None: |
| | assert self.cur_size is None |
| | if cur_size is not None: |
| | self.max_size += cur_size |
| | self.cur_size = cur_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", |
| | "InvalidMessage": ".legacy.exceptions", |
| | "InvalidStatusCode": ".legacy.exceptions", |
| | "RedirectHandshake": ".legacy.exceptions", |
| | "WebSocketProtocolError": ".legacy.exceptions", |
| | }, |
| | ) |
| |
|