Source code for bokeh.protocol.messages.patch_doc

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# Copyright (c) 2012 - 2023, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
#-----------------------------------------------------------------------------

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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 typing import TYPE_CHECKING, Any

# Bokeh imports
from ...core.serialization import Serializer
from ...document.callbacks import invoke_with_curdoc
from ...document.json import PatchJson
from ..message import Message

if TYPE_CHECKING:
    from ...core.has_props import Setter
    from ...document.document import Document
    from ...document.events import DocumentPatchedEvent

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# Globals and constants
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__all__ = (
    'patch_doc',
)

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# General API
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# Dev API
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class patch_doc(Message[PatchJson]):
    ''' Define the ``PATCH-DOC`` message for sending Document patch events
    between remote documents.

    The ``content`` fragment of for this message is has the form:

    .. code-block:: python

        {
            'events'     : <protocol document events>
            'references' : <model references>
        }

    '''

    msgtype = 'PATCH-DOC'

    @classmethod
    def create(cls, events: list[DocumentPatchedEvent], **metadata: Any) -> patch_doc:
        ''' Create a ``PATCH-DOC`` message

        Args:
            events (list) :
                A list of patch events to apply to a document

        Any additional keyword arguments will be put into the message
        ``metadata`` fragment as-is.

        '''
        header = cls.create_header()

        if not events:
            raise ValueError("PATCH-DOC message requires at least one event")

        docs = {event.document for event in events}
        if len(docs) != 1:
            raise ValueError("PATCH-DOC message configured with events for more than one document")

        [doc] = docs
        serializer = Serializer(references=doc.models.synced_references)
        patch_json = PatchJson(events=serializer.encode(events))
        doc.models.flush_synced(lambda model: not serializer.has_ref(model))

        msg = cls(header, metadata, patch_json)

        for buffer in serializer.buffers:
            msg.add_buffer(buffer)

        return msg

    def apply_to_document(self, doc: Document, setter: Setter | None = None) -> None:
        '''

        '''
        invoke_with_curdoc(doc, lambda: doc.apply_json_patch(self.payload, setter=setter))

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# Private API
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# Code
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