Exception 'Unable to find stateless DjangoApp called' or 'NoLayout'

When i was working on some django-plotly-dash charts, i found a strange error happened from time to time, I will see some error like

KeyError at /django_plotly_dash/app/DPD-xxx/
'Unable to find stateless DjangoApp called dpd-xxx'

Sometimes I got an error like

NoLayoutException at /reports/xxx/
Layout must be a dash component or a function that returns a dash component.

Sometime I just got an blank div with text error saying

Error loading layout

BUT if i refresh the pages a few times then the errors just went away and the chart could be displayed correctly.

Have anyone experienced this? Could anyone please help pointing out what i did it wrong?

Thanks!

[GibbsConsulting]

@miaoz2001 good to hear that the error is cleared up. However, what is your motivation behind trying to encapsulate the app within a class view? The app is something that gets used by the template rendered as a result of the response of your view, rather than from within your view.

If you’re looking to control the content of the app based on your view, then take a look at initial_arguments to the template tags - this allows you to instantiate an instance of an app with values from your view.

[miaoz2001]

Thanks! I got it, I should just put all the app, layout, callback in one file and imported all at once, to keep it simple, instead i was trying to put them into a class view, which caused strange errors.

Now it is working anyway However i knid of hope that the app, layout and callback could be enclosed inside of a class view but haven’t figure it out yet

Thanks!