Source code for bokeh.protocol

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# Copyright (c) 2012 - 2018, Anaconda, Inc. All rights reserved.
#
# Powered by the Bokeh Development Team.
#
# The full license is in the file LICENSE.txt, distributed with this software.
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''' Implement and provide message protocols for communication between Bokeh
Servers and clients.

'''

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# Boilerplate
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from __future__ import absolute_import, division, print_function, unicode_literals

import logging
log = logging.getLogger(__name__)

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# Imports
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# Standard library imports

# External imports
from tornado.escape import json_decode

# Bokeh imports
from . import messages
from . import versions
from .exceptions import ProtocolError

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

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# General API
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# Dev API
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[docs]class Protocol(object): ''' Provide a message factory for a given version of the Bokeh Server message protocol. Args: version (str) : a string identifying a protocol version, e.g. "1.0" ''' def __init__(self, version): if version not in versions.spec: raise ProtocolError("Unknown protocol version %r" % version) self._version = version self._messages = dict() for msgtype, revision in versions.spec[version]: self._messages[msgtype] = messages.index[(msgtype, revision)] def __repr__(self): return "Protocol(%r)" % self.version
[docs] def create(self, msgtype, *args, **kwargs): ''' Create a new Message instance for the given type. Args: msgtype (str) : ''' if msgtype not in self._messages: raise ProtocolError("Unknown message type %r for protocol version %s" % (msgtype, self._version)) return self._messages[msgtype].create(*args, **kwargs)
[docs] def assemble(self, header_json, metadata_json, content_json): ''' Create a Message instance assembled from json fragments. Args: header_json (``JSON``) : metadata_json (``JSON``) : content_json (``JSON``) : Returns: message ''' header = json_decode(header_json) if 'msgtype' not in header: log.error("Bad header with no msgtype was: %r", header) raise ProtocolError("No 'msgtype' in header") return self._messages[header['msgtype']].assemble( header_json, metadata_json, content_json )
@property def version(self): return self._version
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