How to reimplement the long-living shared auto-index client?

[weinibuliu]

Hello everyone!

First of all, I'm very excited that NiceGui has finally released version 3.0. I'm delighted to see the many improvements it includes. Therefore, I'm planning to migrate my project from 2.x to 3.x, but I'm running into some difficulties.

My project has almost all elements in the global scope because I'm using NiceGui as a web UI—it only serves a single user, not multiple users. This has the advantage of keeping the frontend and backend completely separate. Furthermore, when I access the page from another device on the local network, NiceGui doesn't need to rebuild a new page, and the content remains consistent across different pages.

I noticed that 3.0 removed the long-living shared client for various reasons, but I suspect it's something I'm relying on (and after initial attempts, it seems to be). Is there any way I can reimplement it myself?

[evnchn]

Hello @weinibuliu. I knew this would come up one day so I memorized things a bit in the codebase.

In NiceGUI 2.x basically the approach boiled down to:

1. Force-enter a Client and build the response for "/"

@app.get('/')
def _get_index(request: Request) -> Response:
    return Client.auto_index_client.build_response(request)

2. Force-enter the context of the Client in the outside-code

Client.auto_index_client = Client(page('/'), request=None).__enter__()  # pylint: disable=unnecessary-dunder-call

3. Various logic to ensure auto-index-client specific (non-)functionality

---

If you really want to share a client (which, again, may or may not work), you only need to do task 1 of the above. See if it works, and get ready to fixing things if it doesn't. Cheers!

[rodja]

We now provide the "script mode" which should work as a drop-in replacement for the shared client in most of the circumstances. I wonder what the problem is in your code base. Can you, please, create a minimum reproducible example? This would allow us and the community to help more efficiently.

[weinibuliu]

We now provide the "script mode" which should work as a drop-in replacement for the shared client in most of the circumstances. I wonder what the problem is in your code base. Can you, please, create a minimum reproducible example? This would allow us and the community to help more efficiently.

Thanks for your reply. I knew I can still put the elements in the global scope like this. In 3.x, it will work.

import time

from nicegui import ui

ui.label(str(time.time()))
ui.run()

But in 3.x, when I open the page on other devices or press F5, it will create a new page so the label will be updated. In 2.x, it will not update. This is why I want to reimplement the long-living shared client.

[evnchn]

Throws error in console but otherwise appears to work as how you expect (not re-ran the inner stuff). Use at your own risk!

import time

from fastapi import Request
from fastapi.responses import Response

from nicegui import Client, app, ui

with Client(ui.page('/')) as my_shared_client:
    ui.label(str(time.time()))


@app.get('/')
def get_index(request: Request) -> Response:
    return my_shared_client.build_response(request)


ui.run()

[weinibuliu]

@evnchn Thanks! I will carefully evaluate the feasibility of this approach to decide whether to transform my project in this way.