#-----------------------------------------------------------------------------
# Copyright (c) 2012 - 2024, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
#-----------------------------------------------------------------------------
''' Implement and provide message protocols for communication between Bokeh
Servers and clients.
'''
#-----------------------------------------------------------------------------
# Boilerplate
#-----------------------------------------------------------------------------
from __future__ import annotations
import logging # isort:skip
log = logging.getLogger(__name__)
#-----------------------------------------------------------------------------
# Imports
#-----------------------------------------------------------------------------
# Standard library imports
import json
from typing import (
TYPE_CHECKING,
Any,
Literal,
overload,
)
# Bokeh imports
from .exceptions import ProtocolError
from .message import Message
from .messages.ack import ack
from .messages.error import error
from .messages.ok import ok
from .messages.patch_doc import patch_doc
from .messages.pull_doc_reply import pull_doc_reply
from .messages.pull_doc_req import pull_doc_req
from .messages.push_doc import push_doc
from .messages.server_info_reply import server_info_reply
from .messages.server_info_req import server_info_req
if TYPE_CHECKING:
from ..core.types import ID
from ..document.document import Document
from ..document.events import DocumentPatchedEvent
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# Globals and constants
#-----------------------------------------------------------------------------
__all__ = (
'Protocol',
)
MessageType = Literal[
"ACK",
"ERROR",
"OK",
"PATCH-DOC",
"PULL-DOC-REPLY",
"PULL-DOC-REQ",
"PUSH-DOC",
"SERVER-INFO-REPLY",
"SERVER-INFO-REQ",
]
SPEC: dict[MessageType, type[Message[Any]]] = {
"ACK": ack,
"ERROR": error,
"OK": ok,
"PATCH-DOC": patch_doc,
"PULL-DOC-REPLY": pull_doc_reply,
"PULL-DOC-REQ": pull_doc_req,
"PUSH-DOC": push_doc,
"SERVER-INFO-REPLY": server_info_reply,
"SERVER-INFO-REQ": server_info_req,
}
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# General API
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#-----------------------------------------------------------------------------
# Dev API
#-----------------------------------------------------------------------------
[docs]
class Protocol:
''' Provide a message factory for the Bokeh Server message protocol.
'''
_messages: dict[MessageType, type[Message[Any]]]
def __init__(self) -> None:
self._messages = SPEC
def __repr__(self) -> str:
return "Protocol()"
@overload
def create(self, msgtype: Literal["ACK"], **metadata: Any) -> ack: ...
@overload
def create(self, msgtype: Literal["ERROR"], request_id: ID, text: str, **metadata: Any) -> error: ...
@overload
def create(self, msgtype: Literal["OK"], request_id: ID, **metadata: Any) -> ok: ...
@overload
def create(self, msgtype: Literal["PATCH-DOC"], events: list[DocumentPatchedEvent], **metadata: Any) -> patch_doc: ...
@overload
def create(self, msgtype: Literal["PULL-DOC-REPLY"], request_id: ID, document: Document, **metadata: Any) -> pull_doc_reply: ...
@overload
def create(self, msgtype: Literal["PULL-DOC-REQ"], **metadata: Any) -> pull_doc_req: ...
@overload
def create(self, msgtype: Literal["PUSH-DOC"], document: Document, **metadata: Any) -> push_doc: ...
@overload
def create(self, msgtype: Literal["SERVER-INFO-REPLY"], request_id: ID, **metadata: Any) -> server_info_reply: ...
@overload
def create(self, msgtype: Literal["SERVER-INFO-REQ"], **metadata: Any) -> server_info_req: ...
[docs]
def create(self, msgtype: MessageType, *args: Any, **kwargs: Any) -> Message[Any]:
''' Create a new Message instance for the given type.
Args:
msgtype (str) :
'''
if msgtype not in self._messages:
raise ProtocolError(f"Unknown message type {msgtype!r} for Bokeh protocol")
return self._messages[msgtype].create(*args, **kwargs) # type: ignore [attr-defined]
[docs]
def assemble(self, header_json: str, metadata_json: str, content_json: str) -> Message[Any]:
''' Create a Message instance assembled from json fragments.
Args:
header_json (``JSON``) :
metadata_json (``JSON``) :
content_json (``JSON``) :
Returns:
message
'''
header = json.loads(header_json)
if 'msgtype' not in header:
log.error(f"Bad header with no msgtype was: {header!r}")
raise ProtocolError("No 'msgtype' in header")
return self._messages[header["msgtype"]].assemble(header_json, metadata_json, content_json)
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# Private API
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#-----------------------------------------------------------------------------
# Code
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