|
|
""" |
|
|
:mod:`websockets.exceptions` defines the following hierarchy of exceptions. |
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|
|
|
* :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` |
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|
|
|
|
""" |
|
|
|
|
|
from __future__ import annotations |
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|
|
|
import warnings |
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|
|
|
from .imports import lazy_import |
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|
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|
__all__ = [ |
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|
"WebSocketException", |
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|
"ConnectionClosed", |
|
|
"ConnectionClosedOK", |
|
|
"ConnectionClosedError", |
|
|
"InvalidURI", |
|
|
"InvalidProxy", |
|
|
"InvalidHandshake", |
|
|
"SecurityError", |
|
|
"ProxyError", |
|
|
"InvalidProxyMessage", |
|
|
"InvalidProxyStatus", |
|
|
"InvalidMessage", |
|
|
"InvalidStatus", |
|
|
"InvalidHeader", |
|
|
"InvalidHeaderFormat", |
|
|
"InvalidHeaderValue", |
|
|
"InvalidOrigin", |
|
|
"InvalidUpgrade", |
|
|
"NegotiationError", |
|
|
"DuplicateParameter", |
|
|
"InvalidParameterName", |
|
|
"InvalidParameterValue", |
|
|
"ProtocolError", |
|
|
"PayloadTooBig", |
|
|
"InvalidState", |
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|
"ConcurrencyError", |
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|
] |
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|
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|
class WebSocketException(Exception): |
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|
""" |
|
|
Base class for all exceptions defined by websockets. |
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|
""" |
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|
class ConnectionClosed(WebSocketException): |
|
|
""" |
|
|
Raised when trying to interact with a closed connection. |
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|
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|
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. |
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|
|
|
""" |
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|
|
|
def __init__( |
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|
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) |
|
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|
|
|
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}" |
|
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|
|
|
@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, |
|
|
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", |
|
|
"InvalidStatusCode": ".legacy.exceptions", |
|
|
"RedirectHandshake": ".legacy.exceptions", |
|
|
"WebSocketProtocolError": ".legacy.exceptions", |
|
|
}, |
|
|
) |
|
|
|
