Working with Dash and Plotly

From Plotly’s getting start guide: “The plotly Python library is an interactive, open-source plotting library that supports over 40 unique chart types covering a wide range of statistical, financial, geographic, scientific, and 3-dimensional use-cases.”

These tools are usable in jupyter notebooks and can also be ran as their own standalone apps using plotly-dash.

Below are two examples using the standard API and the Arrow enabled API to retrieve data as a pandas.DataFrame, and then plotting the results. These examples are based off of the minimal dash app.

Non-Multistream API

from dash import Dash, html, dcc, callback, Output, Input
import plotly.express as px
import pandas as pd
import btrdb

conn = btrdb.connect()
streams = conn.streams_in_collection("YOUR_COLLECTION_HERE")
streamset = conn.streams(*[s.uuid for s in streams])
latest = streamset.latest()
end = min([pt.time for pt in latest])
start = end - btrdb.utils.timez.ns_delta(minutes=5)

df = streamset.filter(start=start, end=end).to_dataframe()

app = Dash(__name__)

app.layout = html.Div([
    html.H1(children='Title of Dash App', style={'textAlign':'center'}),
    dcc.Dropdown(df.columns, id='dropdown-selection'),
    dcc.Graph(id='graph-content')
])

@callback(
    Output('graph-content', 'figure'),
    Input('dropdown-selection', 'value')
)
def update_graph(value):
    dff = df[value]
    return px.line(dff, x=dff.index, y=value)

if __name__ == '__main__':
    app.run(debug=True)

Multistream API

from dash import Dash, html, dcc, callback, Output, Input
import plotly.express as px
import pandas as pd
import btrdb

conn = btrdb.connect()
streams = conn.streams_in_collection("YOUR_COLLECTION_HERE")
streamset = conn.streams(*[s.uuid for s in streams])
latest = streamset.latest()
end = min([pt.time for pt in latest])
start = end - btrdb.utils.timez.ns_delta(minutes=5)

df = streamset.filter(start=start, end=end).arrow_to_dataframe()
df = df.set_index('time')

app = Dash(__name__)

app.layout = html.Div([
    html.H1(children='Title of Dash App', style={'textAlign':'center'}),
    dcc.Dropdown(df.columns, id='dropdown-selection'),
    dcc.Graph(id='graph-content')
])

@callback(
    Output('graph-content', 'figure'),
    Input('dropdown-selection', 'value')
)
def update_graph(value):
    dff = df[value]
    return px.line(dff, x=dff.index, y=value)

if __name__ == '__main__':
    app.run(debug=True)