Prototype Interactive Bokeh Chart

chart_app.py

from bokeh.models import Plot, ColumnDataSource, GlyphRenderer
from bokeh.properties import Instance, Dict, String, Any
from bokeh.server.app import bokeh_app
from bokeh.server.utils.plugins import object_page
from bokeh.models.widgets import HBox, TextInput, VBoxForm, Select
from bokeh.charts import Bar


class ChartApp(HBox):
    """An example of a browser-based, interactive plot with column selection controls."""

    extra_generated_classes = [["ChartApp", "ChartApp", "HBox"]]

    inputs = Instance(VBoxForm)

    text = Instance(TextInput)

    value_select = Instance(Select)
    label_select = Instance(Select)

    plot = Instance(Plot)
    source = Instance(ColumnDataSource)

    data = Dict(String, Any)

    @classmethod
    def create(cls):
        obj = cls()

        obj.data = {'a': [1, 2, 3, 4],
                    'b': [3, 5, 4, 5],
                    'c': ['foo', 'bar', 'foo', 'bar']}

        col_names = list(obj.data.keys())

        obj.value_select = Select(
            title='values', name='value_select',
            options=col_names, value='a'
        )

        obj.label_select = Select(
            title='label', name='label_select',
            options=col_names, value='c'
        )

        plot = Bar(obj.data, values='a', label='c')

        obj.plot = plot

        obj.inputs = VBoxForm(
            children=[
                obj.value_select, obj.label_select
            ]
        )

        obj.children.append(obj.inputs)
        obj.children.append(obj.plot)

        return obj

    def setup_events(self):
        super(ChartApp, self).setup_events()
        if not self.value_select:
            return

        self.value_select.on_change('value', self, 'input_change')
        self.label_select.on_change('value', self, 'input_change')

    def input_change(self, obj, attrname, old, new):
        self.update_data()

    def update_data(self):
        plot = Bar(self.data,
                   values=self.value_select.value,
                   label=self.label_select.value,
                   id=self.plot._id)
        for old, new in zip(self.plot.renderers, plot.renderers):
            if isinstance(old, GlyphRenderer):
                old.data_source.data = new.data_source.data

        self.plot.x_range.factors = plot.x_range.factors
        self.plot.y_range.start = plot.y_range.start
        self.plot.y_range.end = plot.y_range.end


# The following code adds a "/bokeh/chart/" url to the bokeh-server. This
# URL will render this sine wave sliders app. If you don't want to serve this
# applet from a Bokeh server (for instance if you are embedding in a separate
# Flask application), then just remove this block of code.
@bokeh_app.route("/bokeh/chart/")
@object_page("chart")
def make_app():
    app = ChartApp.create()
    return app