How to read json file at regular interval and display in LEDDsiplay

Dash Python
1

I started simple example with dash app but couldnt find some good reference to it. Here i am reading json file once and display it in LEDDisplay and then can change value from slider. Instead i would like to read json file after regular interval where counter value is updated and that i want to show in LEDDisplay. Any recommendations or comments.

# https://dash.plotly.com/dash-daq
import dash
from dash.dependencies import Input, Output
import dash_daq as daq
from dash import dcc
from dash import html
import json
import os


file = open(r'csv_file_test.json')
json_data = json.load(file)

app = dash.Dash(__name__)

app.layout = html.Div([

    daq.LEDDisplay(
        id='entry-LED-display',
        label="Entry Counter",
        labelPosition='top',
        value=json_data['down'],
        size=200,
        color="#190CAF"
    ),     
    dcc.Input(
        id='entry-LED-display-slider',
        type='number',
        value=json_data['down']
    ),       
])

@app.callback(
    Output('entry-LED-display', 'value'),
    Input('entry-LED-display-slider', 'value')
)
def update_output(value):
    return str(value)


if __name__ == '__main__':
    app.server.run(port=8000, host='0.0.0.0')
2

You need to use dcc.Interval that will trigger a callback to load the json file
https://dash.plotly.com/dash-core-components/interval

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