Dash 4.2 WebSockets

:rocket: We’re excited to announce Dash 4.2, which introduces WebSocket callbacks. This is a meaningful shift for Dash apps that need real-time interaction or streaming data. Dash apps can now push updates to the browser while a callback is still running. No Celery setup just to update a progress bar. And no recursive callback tricks previously used.

A few things that stand out:

set_props() can stream updates to the UI instantly during execution
get_prop() lets callbacks read browser state mid-execution
• Persistent callbacks can run for the lifetime of a session and continuously push updates

Read more on our Blog page.

This is great news! :tada:

You can find the docs here:

think of the following …

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