Dash Community
We’re working on a really cool new addition to Dash: An in-browser interactive debugger.
The idea is to make debugging your callbacks easier: whenever an exception occurs, we’ll popup the exception and display an interactive debugger so that you can introspect the variables. We’ll also display front-end error messages to you, so that you don’t need to check the browser’s console.
To start, we’re using the same debugger as Flask (the Werkzeug Debugger)
This work is part of our “Dash - A Pleasant and Productive Developer Experience” project (Projects · plotly · GitHub) which has been funded by an organization (see Consulting, Training & Open-Source Development for more details about sponsoring dash development).
Here’s a simple example of what this looks like:
and the example:
# Playing around with "Dash Dev Tools":
# https://github.com/plotly/dash/issues/292
import dash
from dash.dependencies import Input, Output
import dash_core_components as dcc
import dash_html_components as html
app = dash.Dash()
app.layout = html.Div([
html.H1('Dash Dev Tools'),
dcc.Dropdown(
options=[
{'label': i, 'value': i}
for i in ['nyc', 'la', 'mtl']
],
value='nyc',
id='dropdown'
),
html.Div(id='output')
])
@app.callback(Output('output', 'children'), [Input('dropdown', 'value')])
def update_output(value):
1/0
if __name__ == '__main__':
app.run_server(debug=True)
We need your feedback! Please take it for a spin and let us know what you think 
To get started, see Dash Dev Tools · Issue #292 · plotly/dash · GitHub
