IMAP Related Crash Stack Traces in NextCloud Cron Logs Every Night

[gohrner]

Steps to reproduce

Wait for cron.php error notification mails.

Expected behavior

No error notification mail should appear.

Actual behavior

Error notification mails appear twice a day (?) with the following stack trace:

Error: Call to a member function getBodyPart() on null in /var/www/nextcloud/apps/mail/lib/IMAP/MessageMapper.php:727
Stack trace:
#0 [internal function]: OCA\Mail\IMAP\MessageMapper->OCA\Mail\IMAP\{closure}()
#1 /var/www/nextcloud/apps/mail/lib/IMAP/MessageMapper.php(738): array_map()
#2 /var/www/nextcloud/apps/mail/lib/IMAP/PreviewEnhancer.php(86): OCA\Mail\IMAP\MessageMapper->getBodyStructureData()
#3 /var/www/nextcloud/apps/mail/lib/Service/PreprocessingService.php(81): OCA\Mail\IMAP\PreviewEnhancer->process()
#4 /var/www/nextcloud/apps/mail/lib/BackgroundJob/PreviewEnhancementProcessingJob.php(94): OCA\Mail\Service\PreprocessingService->process()
#5 /var/www/nextcloud/lib/public/BackgroundJob/Job.php(78): OCA\Mail\BackgroundJob\PreviewEnhancementProcessingJob->run()
#6 /var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php(103): OCP\BackgroundJob\Job->start()
#7 /var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php(93): OCP\BackgroundJob\TimedJob->start()
#8 /var/www/nextcloud/cron.php(152): OCP\BackgroundJob\TimedJob->execute()
#9 {main}

Mail app version

2.1.1

Mailserver or service

Dovecot

Operating system

Debian 11 Bullseye

PHP engine version

PHP 7.4

Web server

Apache (supported)

Database

MariaDB

Additional info

Errors seem to have started occuring since the upgrade to NextCloud 25.0.1 and maybe a corresponding mail app update implicitly performed then.

Or it may just be a coincidence and maybe started slightly earlier - not sure.

[miaulalala]

If you're up for it you can check out the linked branch to see if that fixes the issue :)

[gohrner]

@miaulalala: Unfortunately I'm currently not able to test a separate code branch at the moment.

In case I find some time during the weekend, do I just have to clone the repo, check out the mentioned branch and replace the mail app subdirectory on the server with the new version, or do I have to perform some other steps like DB migration?

[roliverio]

I had this issue appear once when i performed a heavy message moving and deleting from outside Nextcloud's Mail app and from my local MUA. (this had never happened until Nextcloud 25 and Mail 2.xx), maybe related?

[jirireischig]

Still exists in version 2.2.1

[ChristophWurst]

@jirireischig thanks for the info. As long as the ticket stays open you can assume that we know that it hasn't been fixed and still exists.