Solara•15mo ago

Authorization example using a Thread/Task is even possible?

Hello!

I'm playing with/studying the Authorization https://solara.dev/apps/authorization/users example.

I'm trying to extend it to show a Spinner / ProgressLinear once the user clicks the Login button because in my use case the login function could take several seconds to finish.

I would like to hide/change the Login button for a spinner.

I have tried several task related methods, trying to make the login function a task, called from LoginForm. But I'm not able to get it properly working, sometimes the spinner is not shown, but the function success (due to user and login_failed hooks sometimes) others it shows it but the app goes crazy. I think it could be related to how Layout and check_auth are being magically managed behind the scenes. I don't know.

At this point, I'm about to throw the towel with this example and try another approach

but before I would like to know if there is an "easy" way to solve this for this example or if this is a deadend and I should indeed take another aproach.

Thanks!

MaartenBreddels•10/7/24, 1:23 PM

I hope this demo helps: https://py.cafe/maartenbreddels/solara-auth-example

Does this work for you? If yes, can you tell us what you did wrong so we can improve the documentation?

PyCafe - Solara - Authorization and authentication example - Solara

Create & Share Streamlit, Dash and Python Apps Online.

PunxsutawneyOP•10/7/24, 2:54 PM

It works now!. Thanks a lot! I see what is different, not sure I understand why it matters so much.

My code differs in that I changed the lambda call to the the global @task decorated task function for a local @task decorated function call because I wanted to do more things locally using the local context... (I'm not using async/coroutines in my code but your approach works now for my code also) ..

This was my NOT working code, the rest is like the original:

@solara.component
def LoginForm():
username = solara.use_reactive("admin")
password = solara.use_reactive("admin")

@solara.lab.task
def check_credentials():
print('check_credentials - enter')
return login(username.value, password.value)

with solara.Card("Login"):
solara.Markdown(
"""
This is an example login form.

use admin/admin to login as admin.
use test/test to login as a normal user.""")

solara.InputText(label="Username", value=username)
solara.InputText(label="Password", password=True, value=password)

solara.Button(label="Login", on_click=check_credentials, disabled=check_credentials.pending)
solara.ProgressLinear(check_credentials.pending)

if check_credentials.value:
solara.Error("Wrong username or password")

MaartenBreddels•10/7/24, 3:04 PM

you keep re-defining the task, because it runs in the body of the component, for this, you should be using use_task

PunxsutawneyOP•10/7/24, 3:18 PM

I see, of course, I do re-redefine it!, thanks for pointing it out. The funny thing is that I use task for other activities and so far everything works pretty well. I even tried some other approaches here using use_task also but I had trouble to activate the task just using the button click, never did this before, I tried making it dependant on a use_reactive variable than was set by the button, but things got a bit messy very quickly and it was not working well....

MaartenBreddels•10/7/24, 3:38 PM

did you make it depend on the reactive variable object, or its value?

MaartenBreddels•10/7/24, 3:38 PM

the value can change, while the reactive variable does not

MaartenBreddels•10/7/24, 3:38 PM

could that be it?