App password invalidated if IMAP auth server not accessible

[duritong]

Affected apps

imap backend

Steps to reproduce

This is a copy over from nextcloud/server#12703

On a nextcloud 14.0.4 installation:

Everytime there seems to be a hickup with the imap server all the app passwords are lost.

This is especially bad, as the nexctloud client retries to auth with the lost app password, where nextcloud then tries to re-auth at the imap server, which might get you eventually locked, because of too many wrong login attempts.

@ChristophWurst mentioned:

On a second thought I'm wondering if it shouldn't be the IMAP user back-end that can store known
users and handle these cases properly with an exception that makes the instance inaccessible in
general as long as the user back-end is unavailable.

If the user back-end tells Nextcloud "this password is wrong" then Nextcloud will do its "wrong
password" procedure.

[ChristophWurst]

Probably resolved as described in nextcloud/server#12703 (comment).

[violoncelloCH]

@duritong is this solved with NC 15?

[duritong]

I am still waiting for a hickup with the imap server, but running on 15.0.2 now ;)

[violoncelloCH]

closing this... if it happens again for you, we can reopen the issue