Notebook demonstrating data streaming with bokeh plots. Unfortunally I have not managed to make it show the plot before the cell finishes execution.

no_plot_until_end_of_cell.ipynb

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import nest_asyncio\n",
    "nest_asyncio.apply()\n",
    "\n",
    "from bokeh.models import ColumnDataSource\n",
    "from bokeh.layouts import row\n",
    "from bokeh.plotting import figure\n",
    "\n",
    "document = None\n",
    "callback = None\n",
    "\n",
    "def modify_doc(doc):\n",
    "    i = 1\n",
    "    data = {\"x_values\": [0],\n",
    "            \"y_values\": [0]}\n",
    "    source = ColumnDataSource(data=data)\n",
    "\n",
    "    opts = dict(plot_width=250, plot_height=250, min_border=0)\n",
    "    p1 = figure(**opts)\n",
    "    p1.circle(x=\"x_values\", y=\"y_values\", source=source, size=5)\n",
    "    doc.add_root(row(p1))\n",
    "    \n",
    "    def update_source():\n",
    "        data = source.data\n",
    "        data[\"x_values\"].append(data[\"x_values\"][-1] + 1)\n",
    "        data[\"y_values\"].append(data[\"y_values\"][-1] + 1)\n",
    "        source.data.update(data)\n",
    "\n",
    "    global callback\n",
    "    callback = doc.add_periodic_callback(update_source, 1000)\n",
    "    global document\n",
    "    document = doc"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stderr",
     "output_type": "stream",
     "text": [
      "WARNING:bokeh.server.util:Host wildcard '*' will allow connections originating from multiple (or possibly all) hostnames or IPs. Use non-wildcard values to restrict access explicitly\n"
     ]
    }
   ],
   "source": [
    "import threading\n",
    "import tornado\n",
    "\n",
    "from bokeh.application.handlers import FunctionHandler\n",
    "from bokeh.application import Application\n",
    "from bokeh.server.server import Server\n",
    "\n",
    "handler = FunctionHandler(modify_doc)\n",
    "app = Application(handler)\n",
    "io_loop = tornado.ioloop.IOLoop.current(instance=True)\n",
    "\n",
    "t = threading.Thread(target=io_loop.start)\n",
    "# t.daemon = True\n",
    "t.start()\n",
    "server = Server({'/': app}, port=5002, host=[\"*\"], allow_websocket_origin=[\"*\"], io_loop=io_loop)\n",
    "server.start()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "\n",
       "<script id=\"1001\">\n",
       "  var xhr = new XMLHttpRequest()\n",
       "  xhr.responseType = 'blob';\n",
       "  xhr.open('GET', \"http://127.0.0.1:5002/autoload.js?bokeh-autoload-element=1001&bokeh-absolute-url=http://127.0.0.1:5002\", true);\n",
       "  \n",
       "  xhr.onload = function (event) {\n",
       "    var script = document.createElement('script'),\n",
       "    src = URL.createObjectURL(event.target.response);\n",
       "    script.src = src;\n",
       "    document.body.appendChild(script);\n",
       "  };\n",
       "xhr.send();\n",
       "</script>"
      ],
      "text/plain": [
       "<IPython.core.display.HTML object>"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    },
    {
     "name": "stderr",
     "output_type": "stream",
     "text": [
      "ERROR:bokeh.protocol:Bad header with no msgtype was: {'events': [{'kind': 'ModelChanged', 'model': {'id': '1006'}, 'attr': 'start', 'new': -0.18761586820851694}, {'kind': 'ModelChanged', 'model': {'id': '1006'}, 'attr': 'end', 'new': 2.2067174651248167}], 'references': []}\n",
      "ERROR:bokeh.server.views.ws:Bokeh Server protocol error: No 'msgtype' in header, closing connection\n",
      "ERROR:bokeh.protocol:Bad header with no msgtype was: {'events': [{'kind': 'ModelChanged', 'model': {'id': '1006'}, 'attr': 'start', 'new': -0.18761586820851694}, {'kind': 'ModelChanged', 'model': {'id': '1006'}, 'attr': 'end', 'new': 2.2067174651248167}], 'references': []}\n",
      "ERROR:bokeh.server.views.ws:Bokeh Server protocol error: No 'msgtype' in header, closing connection\n",
      "ERROR:bokeh.protocol:Bad header with no msgtype was: {'events': [{'kind': 'ModelChanged', 'model': {'id': '1006'}, 'attr': 'start', 'new': -0.18761586820851694}, {'kind': 'ModelChanged', 'model': {'id': '1006'}, 'attr': 'end', 'new': 2.2067174651248167}], 'references': []}\n",
      "ERROR:bokeh.server.views.ws:Bokeh Server protocol error: No 'msgtype' in header, closing connection\n",
      "ERROR:bokeh.protocol:Bad header with no msgtype was: {'events': [{'kind': 'ModelChanged', 'model': {'id': '1006'}, 'attr': 'start', 'new': -0.18761586820851694}, {'kind': 'ModelChanged', 'model': {'id': '1006'}, 'attr': 'end', 'new': 2.2067174651248167}], 'references': []}\n",
      "ERROR:bokeh.server.views.ws:Bokeh Server protocol error: No 'msgtype' in header, closing connection\n"
     ]
    }
   ],
   "source": [
    "import time\n",
    "from IPython.display import HTML, display\n",
    "from bokeh.embed import server_document\n",
    "script = server_document(url=\"http://127.0.0.1:5002/\")\n",
    "display(HTML(script))\n",
    "\n",
    "for i in range(3):\n",
    "    time.sleep(1)\n",
    "\n",
    "document.remove_periodic_callback(callback)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [],
   "source": [
    "document.add_next_tick_callback(document.clear)\n",
    "server.stop()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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