I have a function that is takes quite a while to run due to needing to both load in large datasets from an online database and then process said data to generate a graph. Function looks like this: @app.callback( Output('figure', 'value'), Output('loading-icon-1', 'children'), # Series o…

Hello @matt-buckley , Two things, you could change this callback to a background=True callback, and provide feedback as it processes. Background Callbacks | Dash for Python Documentation | Plotly Use background callbacks to implement long-running callbacks and avoid server timeouts. …

Thanks very much! Sadly dcc.Store doesn’t work for my use case as the datasets are just too large to be supported, but background callbacks look like a good idea. However, the install instruction, pip install dash[diskcache], doesn’t seem to work for me?

[image] matt-buckley: pip install dash[diskcache] Think it should be: pip install "dash[diskcache]"

Also, take a look at the ServerSideOutput under dash-extensions. [image] Show and Tell - Server Side Caching Dash Python The Store component in Dash makes it easy to share state between callbacks . Under the hood, the data are stored as JSON in the browser. This approach i…

Thanks, this worked for installation! Sadly it seems using a background callback displays exactly the same behaviour as a regular one - could this be down to the background manager default settings? Server-side caching is definitely something I’ll look into, but I don’t think would affect the Loadin…

It would mean that you dont have to renew the info every single time, just on demand. After you run it once, subsequent callbacks could use the previously cached info. There isnt much we can do about the long function, but you can make it so it executes in the background, and you can still use the …

Yeah I think it could well be quite useful in reducing loading times, thanks. I’ll see if there are any improvements to dcc.Loading I could add based on this, as it seems that the loading icon is created asynchronously, which is why it sometimes isn’t created until much later if another function is …

dcc.Loading Not Working with Long Function Calls

Dash Python

jinnyzor October 11, 2022, 4:08pm 5

Also, take a look at the ServerSideOutput under dash-extensions.

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dcc.Loading Not Working with Long Function Calls

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