How to transmit user group information via SAML attributes to Nextcloud?

Hey!
New to casdoor as well. And honestly, truly wonderful.
Was able to configure SSO and SAML auth with nextcloud. But now, i'm trying to transmit the group information from the user during the auth and don't know how to do.
Tried through a custom attribute but can only transmit a predefined value, not the current user groups belonging.
Do you have any lead ?
Thanks

can you provide the format of groups you want?

In code level

because it's not a string, it's list

Not sure of what you mean 😅

"AAA|BBB|CCC", or what

AAA is a group, you know what I mean?

yes got it

I m gonna check on nextcloud wiki, brb thank you

From what i've seen, Nextcloud expects multiple ,one per group, under one element
I feel like it doesn't accept other inputs with separators
Do I answer your question ?

Update:
Quite hard to get more accurate information as it's for entreprise support users https://portal.nextcloud.com/article/Authentication/Single-Sign-On-(SSO)/Configuring-Single-Sign-On

can you support it in the code, make a PR?

Sorry, quite unfamiliar with this ? Is PR Pull Request on git ?

yes

Ok will make a PR

Checked a bit deeper, not enough knowledge to offer a code update sorry 😕
Opening an issue instead