Better error messages for file actions failures

⚠️ 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 (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• Nextcloud Server is running on 64bit capable CPU, PHP and OS.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

File actions via the Webinterface such as delete or move, have a chance of failing.
A popup will appear saying 'Error deleting file "Test".' or 'Could not move "Test"'
The nextcloud log does not log anything when this happens.
The webserver log does provide a hint with:
"PUT /remote.php/webdav/sdufghiusdhgu/file5293.txt HTTP/2.0" 201 0 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36 Edg/111.0.1661.54"
"DELETE /remote.php/dav/files/administrator/sdufghiusdhgu/file5293.txt HTTP/2.0" 423 285 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36 Edg/111.0.1661.54"

The webserver code "423" makes me suspect that the filelocking is not releasing its locks properly.

I also believe that the more performance a system has the less likely the problem is to occur. However due to the random nature of the error I am not certain about that.

Steps to reproduce

1. Upload Folder containing hundreds or even thousands of files
2. Go into folder and select all files
3. Delete files
4. Sometimes some of the files wont get deleted and the error 'Error deleting file "Test".' pops up.

Expected behavior

1. Upload Folder containing hundreds or even thousands of files
2. Go into folder and select all files
3. Delete files
4. All files get deleted reliably or at least the log tells me why it failed

Installation method

Community Manual installation with Archive

Nextcloud Server version

26

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.1

Web server

Nginx

Database engine version

MySQL

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

Fresh Nextcloud Server install

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

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

Configuration report

{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "***REMOVED SENSITIVE VALUE***"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "26.0.0.11",
        "overwrite.cli.url": "https:\/\/***REMOVED SENSITIVE VALUE***",
        "overwritehost": "***REMOVED SENSITIVE VALUE***",
        "overwriteprotocol": "https",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "3306",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "default_phone_region": "de",
        "default_language": "de_DE",
        "default_locale": "de_DE",
        "memcache.local": "\\OC\\Memcache\\APCu",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 0,
            "timeout": 0
        },
        "mail_smtpmode": "smtp",
        "mail_smtpsecure": "tls",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauthtype": "LOGIN",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "587",
        "mail_smtpauth": 1,
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "maintenance": false,
        "theme": "",
        "loglevel": 3,
        "log_authfailip": true,
        "twofactor_enforced": "true",
        "twofactor_enforced_groups": [
            "fatestgroup"
        ],
        "twofactor_enforced_excluded_groups": [
            "admin"
        ],
        "updater.release.channel": "stable",
        "app_install_overwrite": [
            "files_lock",
            "files_pdfviewer",
            "groupfolders",
            "files_antivirus"
        ],
        "allow_local_remote_servers": true,
        "defaultapp": "files",
        "trashbin_retention_obligation": "7, 7",
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***"
    }
}

List of activated Apps

Enabled:
  - activity: 2.18.0
  - admin_audit: 1.16.0
  - bruteforcesettings: 2.6.0
  - calendar: 4.3.1
  - circles: 26.0.0
  - cloud_federation_api: 1.9.0
  - comments: 1.16.0
  - contacts: 5.2.0
  - contactsinteraction: 1.7.0
  - dashboard: 7.6.0
  - dav: 1.25.0
  - external: 5.1.0
  - federatedfilesharing: 1.16.0
  - federation: 1.16.0
  - files: 1.21.1
  - files_accesscontrol: 1.16.0
  - files_antivirus: 4.0.3
  - files_automatedtagging: 1.16.1
  - files_downloadactivity: 1.16.0
  - files_external: 1.18.0
  - files_lock: 26.0.0
  - files_pdfviewer: 2.7.0
  - files_retention: 1.15.0
  - files_rightclick: 1.5.0
  - files_sharing: 1.18.0
  - files_trashbin: 1.16.0
  - files_versions: 1.19.1
  - firstrunwizard: 2.15.0
  - forms: 3.2.0
  - group_default_quota: 0.1.6
  - groupfolders: 14.0.0
  - logreader: 2.11.0
  - lookup_server_connector: 1.14.0
  - mail: 3.0.2
  - nextcloud_announcements: 1.15.0
  - notifications: 2.14.0
  - notify_push: 0.6.2
  - oauth2: 1.14.0
  - password_policy: 1.16.0
  - photos: 2.2.0
  - privacy: 1.10.0
  - provisioning_api: 1.16.0
  - recommendations: 1.5.0
  - related_resources: 1.1.0-alpha1
  - richdocuments: 8.0.0
  - serverinfo: 1.16.0
  - settings: 1.8.0
  - sharebymail: 1.16.0
  - spreed: 16.0.2
  - support: 1.9.0
  - survey_client: 1.14.0
  - systemtags: 1.16.0
  - text: 3.7.2
  - theming: 2.1.1
  - twofactor_admin: 4.1.9
  - twofactor_backupcodes: 1.15.0
  - twofactor_email: 2.7.2
  - updatenotification: 1.16.0
  - user_status: 1.6.0
  - viewer: 1.10.0
  - weather_status: 1.6.0
  - workflowengine: 2.8.0
Disabled:
  - drawio: 2.1.0 (installed 2.1.0)
  - electronicsignatures: 2.0.3 (installed 2.0.3)
  - encryption: 2.14.0 (installed 2.12.0)
  - files_fulltextsearch: 25.0.0 (installed 25.0.0)
  - fulltextsearch: 25.0.0 (installed 25.0.0)
  - fulltextsearch_elasticsearch: 25.0.0 (installed 25.0.0)
  - impersonate: 1.13.0 (installed 1.13.0)
  - richdocumentscode: 22.5.802 (installed 22.5.802)
  - suspicious_login: 4.4.0 (installed 4.1.0)
  - theming_customcss: 1.13.0 (installed 1.13.0)
  - twofactor_totp: 8.0.0-alpha.0 (installed 8.0.0-alpha.0)
  - user_ldap: 1.16.0 (installed 1.16.0)

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

Empty Logs

Additional info

I also encountered the issue on a nextcloud v25 kubernetes cluster, nextcloud v25 aio, aswell as the most simplistic lamp stack installation I could think of . Which makes me suspect the issue can be reproduced on any setup.

Start with the file-action requests at remote.php/webdav and remote.php/dav, especially the DELETE response showing HTTP 423, and trace how the file-locking failure reaches the web interface. Reproduce the bulk-delete steps with many files and compare the Nextcloud and webserver logs; done means failures are reliably handled or explain their cause in the log.