Streaming data with Bokeh and Panel periodic callbacks?

Panel
19

Full working example, which requires current master or Panel >=0.10.0a18 (to be released tomorrow), to work:

import panel as pn
import param
from tornado.ioloop import IOLoop
from bokeh.plotting import figure
from bokeh.models import ColumnDataSource
import numpy as np


class Application(param.Parameterized):
    do_calc = param.Action(lambda self: self._do_calc())

    def __init__(self, **params):
        super(Application, self).__init__(**params)
        self.source = ColumnDataSource({"x": range(10), "y": range(10)})
        self.figure = figure()
        self.figure.line(x="x", y="y", source=self.source)
        self.col = pn.Column(
            pn.pane.Markdown("## Title"),
            self.param.do_calc,
            self.figure,
        )
        pn.state.add_periodic_callback(self._do_calc, 200)  # <- this line does not work properly

    def _do_calc(self):
        data = list(np.random.randint(0, 2 ** 31, 10))
        self.source.data.update({"y": data})

    def panel(self):
        return self.col


def create_app():
    app = Application()
    return app.panel()

loop = IOLoop().current()
server = pn.serve(create_app, show=False, loop=loop, start=False, port=5006)

# Do stuff

server.io_loop.start()
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