Pass Error status in /dev/reload stream

[freddyaboulton]

Description

Let clients know when an error happened during reload. Also refactored the route to support more than one client connecting simultaneously.

Logic is here and should not conflict with #8056 but will wait for #8056

There are two message types in the thread reload and error.

Edit: also errors are shown in the UI now

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[gradio-pr-bot]

🪼 branch checks and previews

•	Name	Status	URL
	Spaces	ready!	Spaces preview
	Website	ready!	Website preview
	Storybook	failed!	Details
🦄	Changes	detected!	Details

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/7f6c699dc9626b3c0cf2e707c963fbdc169bc565/gradio-4.28.3-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@7f6c699dc9626b3c0cf2e707c963fbdc169bc565#subdirectory=client/python"

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/app	patch
gradio	patch

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Pass Error status in /dev/reload stream

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[pngwn]

I think it would be nice to show the full trace here but I guess the error toast is too small for that?

[freddyaboulton]

I think so and they should have access to the server logs anyways (that's the idea on spaces as well I believe)

[pngwn]

Would be cool if it was all viewable in the browser tho, on a single screen you often have to choose 2 of browser, terminal, editor. Can discuss later anyway, this is much better DX!

[pngwn]

Tested and works great! Thanks @freddyaboulton!

[freddyaboulton]

Just added the python traceback to the console! Thanks for the review @pngwn

[aliabid94]

nit: could use this internally in Block.svelte whenever we add a message too

[aliabid94]

Looks great, thanks freddy! Only thought is if I wonder if the error message should show more than just "Error reloading app", maybe the actual traceback?

EDIT: just saw that was discussed above.

Also, I wish the reload error toast would go away immediately as soon as I fixed the app, but that's probably a bit tricky.

[freddyaboulton]

Thanks for the review @aliabid94 ! Will think about how we can close the error toast automatically!

[pngwn]

Also, I wish the reload error toast would go away immediately as soon as I fixed the app, but that's probably a bit tricky.

I think this should be possible.

If each error message takes an id of the fn_index, then when we change the status of that fn_index to 'not an error' we can call a 'close_message' function on the Toast component (export one) that could filter out toasts with the given id. This is probably a good idea for all statuses tbh, because after the fn has run again those status are stale and irrelevant.

[pngwn]

We need to refactor the progress stuff tbh it has gotten a bit out of hand, very hard to parse now. One problem @freddyaboulton and I came across is that the loading status centres around components, changing statuses for functions is harder than we felt it should be. Can look into it.