Source code for bokeh.client.states

#-----------------------------------------------------------------------------
# Copyright (c) 2012 - 2021, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
#-----------------------------------------------------------------------------
''' Provide a set of objects to represent different stages of a connection
to a Bokeh server.

'''

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# Boilerplate
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from __future__ import annotations

import logging # isort:skip
log = logging.getLogger(__name__)

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# Imports
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# Standard library imports
from abc import ABCMeta, abstractmethod
from enum import Enum, auto
from typing import TYPE_CHECKING, Any

# Bokeh imports
from ..core.types import ID

if TYPE_CHECKING:
    from ..protocol.message import Message
    from .connection import ClientConnection

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# Globals and constants
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__all__ = (
    'CONNECTED_BEFORE_ACK',
    'CONNECTED_AFTER_ACK',
    'DISCONNECTED',
    'ErrorReason',
    'NOT_YET_CONNECTED',
    'WAITING_FOR_REPLY',
)

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# General API
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#-----------------------------------------------------------------------------
# Dev API
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[docs]class ErrorReason(Enum): NO_ERROR = auto() HTTP_ERROR = auto() NETWORK_ERROR = auto()
class State(metaclass=ABCMeta): @abstractmethod async def run(self, connection: ClientConnection) -> None: pass
[docs]class NOT_YET_CONNECTED(State): ''' The ``ClientConnection`` is not yet connected. ''' async def run(self, connection: ClientConnection) -> None: await connection._connect_async()
[docs]class CONNECTED_BEFORE_ACK(State): ''' The ``ClientConnection`` connected to a Bokeh server, but has not yet received an ACK from it. ''' async def run(self, connection: ClientConnection) -> None: await connection._wait_for_ack()
[docs]class CONNECTED_AFTER_ACK(State): ''' The ``ClientConnection`` connected to a Bokeh server, and has received an ACK from it. ''' async def run(self, connection: ClientConnection) -> None: await connection._handle_messages()
[docs]class DISCONNECTED(State): ''' The ``ClientConnection`` was connected to a Bokeh server, but is now disconnected. '''
[docs] def __init__(self, reason: ErrorReason = ErrorReason.NO_ERROR, error_code: int | None = None, error_detail: str = "") -> None: ''' Constructs a DISCONNECT-State with given reason (``ErrorReason`` enum), error id and additional information provided as string. ''' self._error_code = error_code self._error_detail = error_detail self._error_reason = reason
@property def error_reason(self) -> ErrorReason: ''' The reason for the error encoded as an enumeration value. ''' return self._error_reason @property def error_code(self) -> int | None: ''' Holds the error code, if any. None otherwise. ''' return self._error_code @property def error_detail(self) -> str: ''' Holds the error message, if any. Empty string otherwise. ''' return self._error_detail async def run(self, connection: ClientConnection) -> None: return
[docs]class WAITING_FOR_REPLY(State): ''' The ``ClientConnection`` has sent a message to the Bokeh Server which should generate a paired reply, and is waiting for the reply. ''' _reply: Message[Any] | None def __init__(self, reqid: ID) -> None: self._reqid = reqid self._reply = None @property def reply(self) -> Message[Any] | None: ''' The reply from the server. (``None`` until the reply arrives) ''' return self._reply @property def reqid(self) -> ID: ''' The request ID of the originating message. ''' return self._reqid async def run(self, connection: ClientConnection) -> None: message = await connection._pop_message() if message is None: await connection._transition_to_disconnected(DISCONNECTED(ErrorReason.NETWORK_ERROR)) elif 'reqid' in message.header and message.header['reqid'] == self.reqid: self._reply = message await connection._transition(CONNECTED_AFTER_ACK()) else: await connection._next()
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