[Bug]: workflow engine - no backgroundjobs created for trigger "tag assigned"

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

I tried to set up various flows. Tried both in the admin panel as well as user. The flows don´t run, however. Trying to troubleshoot, I checked the database (Mariadb) and found, that in the oc_background-jobs (or called similar) table no entry for “OCA/workflow” is created as it should (tried to implement workflow_ocr and PDF-conversion workflow as well as notification workflow). The cron job seems to be running without issues.
I think the issue might lay in the workflow engine itself.

Steps to reproduce

1. install workflow plugin (pdf-converter, pdf-ocr, notification-workflow)
2. set up (tag assigned, file created and any combination of these)
3. wait for cron job (or force it)
4. expected behavior: get notification after a tag was assigned, get a .odt converted to PDF, get OCR done on a PDF or a jpg.

Expected behavior

expected behavior: get notification after a tag was assigned, get a .odt converted to PDF, get OCR done on a PDF or a jpg.

Installation method

Other Community project

Nextcloud Server version

27

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.2

Web server

Nginx

Database engine version

MariaDB

Is this bug present after an update or on a fresh install?

Fresh Nextcloud Server install

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

{
    "system": {
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "******************",
            "192.168.178.201"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "27.0.1.2",
        "overwrite.cli.url": "https:\/\/*************",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "default_language": "de",
        "enable_previews": true,
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "overwritehost": "cloud.mikoshi.de",
        "activity_expire_days": 14,
        "allow_local_remote_servers": true,
        "auth.bruteforce.protection.enabled": true,
        "blacklisted_files": [
            ".htaccess",
            "Thumbs.db",
            "thumbs.db"
        ],
        "cron_log": true,
        "default_phone_region": "DE",
        "enabledPreviewProviders": [
            "OC\\Preview\\PNG",
            "OC\\Preview\\JPEG",
            "OC\\Preview\\GIF",
            "OC\\Preview\\BMP",
            "OC\\Preview\\XBitmap",
            "OC\\Preview\\Movie",
            "OC\\Preview\\PDF",
            "OC\\Preview\\MP3",
            "OC\\Preview\\TXT",
            "OC\\Preview\\MarkDown"
        ],
        "filesystem_check_changes": 0,
        "filelocking.enabled": "true",
        "htaccess.RewriteBase": "\/",
        "integrity.check.disabled": false,
        "knowledgebaseenabled": false,
        "log_rotate_size": "104857600",
        "logfile": "\/var\/log\/nextcloud\/nextcloud.log",
        "loglevel": 2,
        "logtimezone": "Europe\/Berlin",
        "memcache.local": "\\OC\\Memcache\\APCu",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "overwriteprotocol": "https",
        "preview_max_x": 1024,
        "preview_max_y": 768,
        "preview_max_scale_factor": 1,
        "preview_libreoffice_path": "\/usr\/bin\/libreoffice",
        "profile.enabled": false,
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 0,
            "password": "***REMOVED SENSITIVE VALUE***",
            "timeout": 0.5,
            "dbindex": 1
        },
        "quota_include_external_storage": false,
        "share_folder": "\/Freigaben",
        "skeletondirectory": "",
        "trashbin_retention_obligation": "auto, 7",
        "mail_smtpmode": "smtp",
        "mail_smtpsecure": "ssl",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "465",
        "mail_smtpauth": 1,
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "simpleSignUpLink.shown": false,
        "maintenance": false,
        "default_locale": "de_DE",
        "data-fingerprint": "fead994bf6459f6edb3f3a9caf8a4bf6",
        "updater.release.channel": "stable",
        "maintenance_window_start": 1
    }
}

List of activated Apps

Enabled:
  - activity: 2.19.0
  - admin_audit: 1.17.0
  - analytics: 4.9.4
  - announcementcenter: 6.6.1
  - bruteforcesettings: 2.7.0
  - calendar: 4.4.4
  - circles: 27.0.1
  - cloud_federation_api: 1.10.0
  - comments: 1.17.0
  - contacts: 5.3.2
  - contactsinteraction: 1.8.0
  - dashboard: 7.7.0
  - dav: 1.27.0
  - deck: 1.10.0
  - end_to_end_encryption: 1.13.1
  - federatedfilesharing: 1.17.0
  - files: 1.22.0
  - files_accesscontrol: 1.17.0
  - files_automatedtagging: 1.17.0
  - files_pdfviewer: 2.8.0
  - files_rightclick: 1.6.0
  - files_sharing: 1.19.0
  - files_trashbin: 1.17.0
  - files_versions: 1.20.0
  - flow_notifications: 1.7.0
  - forms: 3.3.1
  - groupfolders: 15.0.1
  - guests: 2.5.0
  - integration_github: 2.0.6
  - integration_openai: 1.0.11
  - integration_replicate: 1.0.7
  - logreader: 2.12.0
  - lookup_server_connector: 1.15.0
  - mail: 3.2.5
  - music: 1.8.4
  - news: 22.0.0
  - nextcloud_announcements: 1.16.0
  - notes: 4.8.1
  - notifications: 2.15.0
  - oauth2: 1.15.1
  - password_policy: 1.17.0
  - photos: 2.3.0
  - previewgenerator: 5.3.0
  - privacy: 1.11.0
  - provisioning_api: 1.17.0
  - recommendations: 1.6.0
  - registration: 2.2.0
  - related_resources: 1.2.0
  - richdocuments: 8.1.1
  - richdocumentscode: 23.5.202
  - root_cache_cleaner: 0.1.5
  - serverinfo: 1.17.0
  - settings: 1.9.0
  - sharebymail: 1.17.0
  - side_menu: 3.10.3
  - spreed: 17.0.3
  - suspicious_login: 5.0.0
  - systemtags: 1.17.0
  - terms_of_service: 2.2.0
  - text: 3.8.0
  - theming: 2.2.0
  - translate: 1.1.6
  - twofactor_backupcodes: 1.16.0
  - twofactor_nextcloud_notification: 3.7.0
  - twofactor_totp: 9.0.0
  - updatenotification: 1.17.0
  - user_status: 1.7.0
  - viewer: 2.1.0
  - weather_status: 1.7.0
  - workflow_ocr: 1.27.1
  - workflow_pdf_converter: 1.12.0
  - workflowengine: 2.9.0
Disabled:
  - encryption: 2.15.0 (installed 2.15.0)
  - federation: 1.17.0 (installed 1.17.0)
  - files_external: 1.19.0
  - firstrunwizard: 2.16.0 (installed 2.16.0)
  - maps: 1.1.0 (installed 1.1.0)
  - support: 1.10.0 (installed 1.10.0)
  - survey_client: 1.15.0 (installed 1.15.0)
  - talk_matterbridge: 1.26.0
  - user_ldap: 1.17.0

Nextcloud Signing status

signed

Nextcloud Logs

{"reqId":"8dELPKLLUGdwxtQmU2kJ","level":3,"time":"2023-08-08T22:35:01+02:00","remoteAddr":"","user":"--","app":"core","method":"","url":"--","message":"Error while running background job (class: OCA\\GroupFolders\\BackgroundJob\\ExpireGroupVersions, arguments: )","userAgent":"--","version":"27.0.1.2","exception":{"Exception":"TypeError","Message":"OCA\\GroupFolders\\ACL\\ACLManagerFactory::getACLManager(): Argument #1 ($user) must be of type OCP\\IUser, null given, called in /var/www/nextcloud/apps/groupfolders/lib/Mount/MountProvider.php on line 206","Code":0,"Trace":[{"file":"/var/www/nextcloud/apps/groupfolders/lib/Mount/MountProvider.php","line":206,"function":"getACLManager","class":"OCA\\GroupFolders\\ACL\\ACLManagerFactory","type":"->"},{"file":"/var/www/nextcloud/apps/groupfolders/lib/Versions/VersionsBackend.php","line":172,"function":"getMount","class":"OCA\\GroupFolders\\Mount\\MountProvider","type":"->"},{"file":"/var/www/nextcloud/apps/groupfolders/lib/Versions/GroupVersionsExpireManager.php","line":68,"function":"getAllVersionedFiles","class":"OCA\\GroupFolders\\Versions\\VersionsBackend","type":"->"},{"file":"/var/www/nextcloud/apps/groupfolders/lib/Versions/GroupVersionsExpireManager.php","line":59,"function":"expireFolder","class":"OCA\\GroupFolders\\Versions\\GroupVersionsExpireManager","type":"->"},{"file":"/var/www/nextcloud/apps/groupfolders/lib/BackgroundJob/ExpireGroupVersions.php","line":43,"function":"expireAll","class":"OCA\\GroupFolders\\Versions\\GroupVersionsExpireManager","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/Job.php","line":86,"function":"run","class":"OCA\\GroupFolders\\BackgroundJob\\ExpireGroupVersions","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php","line":103,"function":"start","class":"OCP\\BackgroundJob\\Job","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php","line":93,"function":"start","class":"OCP\\BackgroundJob\\TimedJob","type":"->"},{"file":"/var/www/nextcloud/cron.php","line":152,"function":"execute","class":"OCP\\BackgroundJob\\TimedJob","type":"->"}],"File":"/var/www/nextcloud/apps/groupfolders/lib/ACL/ACLManagerFactory.php","Line":37,"message":"Error while running background job (class: OCA\\GroupFolders\\BackgroundJob\\ExpireGroupVersions, arguments: )","exception":[],"CustomMessage":"Error while running background job (class: OCA\\GroupFolders\\BackgroundJob\\ExpireGroupVersions, arguments: )"},"id":"64d2a8812b3dd"}

Additional info

install method: bare metal, manual

Reproduce one workflow from the listed steps, then start at cron.php and inspect the background-jobs table while the workflowengine, workflow_ocr, or workflow_pdf_converter apps are enabled. Compare the observed job creation with the reported GroupFolders background-job error in apps/groupfolders/lib/BackgroundJob/ExpireGroupVersions.php. Done means the selected trigger creates and runs its background job and performs the expected action.