Exceptions - websockets 12.0 documentation
Description: websockets.exceptions defines the following exception hierarchy:- WebSocketException,-- ConnectionClosed,- ConnectionClosedError, ConnectionClosedOK.,.,- InvalidHandshake,- SecurityError, InvalidMe...

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# Exceptions

`websockets.exceptions` defines the following exception hierarchy:

- `WebSocketException`
    - `ConnectionClosed`

        - `ConnectionClosedError`

        - `ConnectionClosedOK`

    - `InvalidHandshake`

        - `SecurityError`

        - `InvalidMessage`

        - `InvalidHeader`

            - `InvalidHeaderFormat`

            - `InvalidHeaderValue`

            - `InvalidOrigin`

            - `InvalidUpgrade`

        - `InvalidStatus`

        - `InvalidStatusCode` (legacy)

        - `NegotiationError`

            - `DuplicateParameter`

            - `InvalidParameterName`

            - `InvalidParameterValue`

        - `AbortHandshake`

        - `RedirectHandshake`

    - `InvalidState`

    - `InvalidURI`

    - `PayloadTooBig`

    - `ProtocolError`

exception websockets.exceptions.AbortHandshake(status, headers, body=b'')

  Raised to abort the handshake on purpose and return an HTTP response.

  This exception is an implementation detail.

  The public API is `process_request()`.

  status

    HTTP status code.

    Type:

      HTTPStatus

  headers

    HTTP response headers.

    Type:

      Headers

  body

    HTTP response body.

    Type:

      bytes

exception websockets.exceptions.ConnectionClosed(rcvd, sent, rcvd_then_sent=None)

  Raised when trying to interact with a closed connection.

  rcvd

    if a close frame was received, its code and reason are available in `rcvd.code` and `rcvd.reason`.

    Type:

      Optional[Close]

  sent

    if a close frame was sent, its code and reason are available in `sent.code` and `sent.reason`.

    Type:

      Optional[Close]

  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.

    Type:

      Optional[bool]

exception websockets.exceptions.ConnectionClosedError(rcvd, sent, rcvd_then_sent=None)

  Like `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.

exception websockets.exceptions.ConnectionClosedOK(rcvd, sent, rcvd_then_sent=None)

  Like `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.

exception websockets.exceptions.DuplicateParameter(name)

  Raised when a parameter name is repeated in an extension header.

exception websockets.exceptions.InvalidHandshake

  Raised during the handshake when the WebSocket connection fails.

exception websockets.exceptions.InvalidHeader(name, value=None)

  Raised when an HTTP header doesn’t have a valid format or value.

exception websockets.exceptions.InvalidHeaderFormat(name, error, header, pos)

  Raised when an HTTP header cannot be parsed.

  The format of the header doesn’t match the grammar for that header.

exception websockets.exceptions.InvalidHeaderValue(name, value=None)

  Raised when an HTTP header has a wrong value.

  The format of the header is correct but a value isn’t acceptable.

exception websockets.exceptions.InvalidMessage

  Raised when a handshake request or response is malformed.

exception websockets.exceptions.InvalidOrigin(origin)

  Raised when the Origin header in a request isn’t allowed.

exception websockets.exceptions.InvalidParameterName(name)

  Raised when a parameter name in an extension header is invalid.

exception websockets.exceptions.InvalidParameterValue(name, value)

  Raised when a parameter value in an extension header is invalid.

exception websockets.exceptions.InvalidState

  Raised when an operation is forbidden in the current state.

  This exception is an implementation detail.

  It should never be raised in normal circumstances.

exception websockets.exceptions.InvalidStatus(response)

  Raised when a handshake response rejects the WebSocket upgrade.

exception websockets.exceptions.InvalidStatusCode(status_code, headers)

  Raised when a handshake response status code is invalid.

exception websockets.exceptions.InvalidURI(uri, msg)

  Raised when connecting to a URI that isn’t a valid WebSocket URI.

exception websockets.exceptions.InvalidUpgrade(name, value=None)

  Raised when the Upgrade or Connection header isn’t correct.

exception websockets.exceptions.NegotiationError

  Raised when negotiating an extension fails.

exception websockets.exceptions.PayloadTooBig

  Raised when receiving a frame with a payload exceeding the maximum size.

exception websockets.exceptions.ProtocolError

  Raised when a frame breaks the protocol.

exception websockets.exceptions.RedirectHandshake(uri)

  Raised when a handshake gets redirected.

  This exception is an implementation detail.

exception websockets.exceptions.SecurityError

  Raised when a handshake request or response breaks a security rule.

  Security limits are hard coded.

exception websockets.exceptions.WebSocketException

  Base class for all exceptions defined by websockets.

websockets.exceptions.WebSocketProtocolError

  alias of `ProtocolError`