Python Dash - callback value from another file

0
votes

I create a dashboard based on flask and dash python
How can I refresh data pulled from another .py file with a specified interval? I have a weather_api.py file that returns data from openweathermap API and I refer to it such as:

html.Div(children=[
        html.Div(children=[html.Img(src="http://openweathermap.org/img/wn/{}@2x.png".format(WEATHER_API.icon))]),
        html.Div(children=[html.H2("{} ".format(round(WEATHER_API.current_temperature))),
        html.Span(["Data", html.Br()]),
        html.Span("{}".format(WEATHER_API.weather_description))]),
        ])
])

at the beginning of the file I import WEATHER_API - and then it will refer to variables e.g.: html.Span("{}".format(WEATHER_API.weather_description))

I would like this data to be refreshed every e.g. 10 minutes - now it works so that the data is only from the beginning - as soon as I run the Dash, it "pulls" data from the API only once. Is it possible to somehow set up @callback to retrieve data from WEATHER_API every 10 minutes - as if starting WEATHER_API.py every 10 minutes?

2
pythonflaskplotly-dash

2 Answers

1
votes

Yes. You need the interval component.

Here are some examples of it in use to provide live updates.

1
votes

I found a solution - you can easily return a function value from another script - all you need is a proper reference:

import script.py

app.layout = html.Div(
    [

        html.Div(id="number-output"),
        dcc.Interval(id='interval-component',
interval=1000,  # in millisecondsn_intervals=0
        ),
    ]
)


@app.callback(Output('number-output', 'children'),
              [Input('interval-component', 'n_intervals')])

def update_output(n):
    return html.Span('Output: {}'.format(script.test()))

A useful example: https://dash.plotly.com/live-updates