#!/usr/bin/env python

from time import sleep
from random import random
from bokeh.plotting import curdoc, figure
from bokeh.models import ColumnDataSource

data = {
    "x": [0, 1, 2, 3, 4],
    "y": [6, 7, 2, 3, 5]
}

i = len(data["x"])

source = ColumnDataSource(data=data)

p = figure()
p.line(x="x", y="y", source=source)


def update():
    global i
    i += 1

    new = {
        "x": [i],
        "y": [random()*10]
    }

    source.stream(new, rollover=50)



doc = curdoc()
doc.add_periodic_callback(update, 500)
doc.add_root(p)