Dataset must contain samples with exactly 3 dimensions, 4 given

Steps to reproduce

1. Have users on your installation with set up mail accounts
2. Have suspicious login also enabled (might be important)
3. Run cron jobs

Expected behavior

Nothing happens in the logs

Actual behavior

Our log shows this error 506 times for the last 2 weeks:

{
  "reqId": "jF18I3StppDQxCchnn0q",
  "level": 3,
  "time": "2022-03-22T16:50:50+00:00",
  "remoteAddr": "",
  "user": "--",
  "app": "mail",
  "method": "",
  "url": "--",
  "message": "Cron mail sync failed for account 65",
  "userAgent": "--",
  "version": "23.0.3.2",
  "exception": {
    "Exception": "OCA\\Mail\\Exception\\ServiceException",
    "Message": "Sync failed for 65:INBOX: Dataset must contain samples with exactly 3 dimensions, 4 given.",
    "Code": 0,
    "Trace": [
      {
        "file": "/var/www/html/apps/mail/lib/Service/Sync/ImapToDbSynchronizer.php",
        "line": 135,
        "function": "sync",
        "class": "OCA\\Mail\\Service\\Sync\\ImapToDbSynchronizer",
        "type": "->"
      },
      {
        "file": "/var/www/html/apps/mail/lib/BackgroundJob/SyncJob.php",
        "line": 109,
        "function": "syncAccount",
        "class": "OCA\\Mail\\Service\\Sync\\ImapToDbSynchronizer",
        "type": "->"
      },
      {
        "file": "/var/www/html/lib/public/BackgroundJob/Job.php",
        "line": 79,
        "function": "run",
        "class": "OCA\\Mail\\BackgroundJob\\SyncJob",
        "type": "->"
      },
      {
        "file": "/var/www/html/lib/public/BackgroundJob/TimedJob.php",
        "line": 95,
        "function": "execute",
        "class": "OCP\\BackgroundJob\\Job",
        "type": "->"
      },
      {
        "file": "/var/www/html/cron.php",
        "line": 150,
        "function": "execute",
        "class": "OCP\\BackgroundJob\\TimedJob",
        "type": "->"
      }
    ],
    "File": "/var/www/html/apps/mail/lib/Service/Sync/ImapToDbSynchronizer.php",
    "Line": 249,
    "Previous": {
      "Exception": "Rubix\\ML\\Exceptions\\IncorrectDatasetDimensionality",
      "Message": "Dataset must contain samples with exactly 3 dimensions, 4 given.",
      "Code": 0,
      "Trace": [
        {
          "file": "/var/www/html/apps/suspicious_login/vendor/rubix/ml/src/Classifiers/GaussianNB.php",
          "line": 297,
          "function": "check",
          "class": "Rubix\\ML\\Specifications\\DatasetHasDimensionality",
          "type": "->"
        },
        {
          "file": "/var/www/html/apps/mail/lib/Service/Classification/ImportanceClassifier.php",
          "line": 327,
          "function": "predict",
          "class": "Rubix\\ML\\Classifiers\\GaussianNB",
          "type": "->"
        },
        {
          "file": "/var/www/html/apps/mail/lib/Listener/NewMessageClassificationListener.php",
          "line": 118,
          "function": "classifyImportance",
          "class": "OCA\\Mail\\Service\\Classification\\ImportanceClassifier",
          "type": "->"
        },
        {
          "file": "/var/www/html/lib/private/EventDispatcher/ServiceEventListener.php",
          "line": 87,
          "function": "handle",
          "class": "OCA\\Mail\\Listener\\NewMessageClassificationListener",
          "type": "->"
        },
        {
          "file": "/var/www/html/3rdparty/symfony/event-dispatcher/EventDispatcher.php",
          "line": 251,
          "function": "__invoke",
          "class": "OC\\EventDispatcher\\ServiceEventListener",
          "type": "->"
        },
        {
          "file": "/var/www/html/3rdparty/symfony/event-dispatcher/EventDispatcher.php",
          "line": 73,
          "function": "callListeners",
          "class": "Symfony\\Component\\EventDispatcher\\EventDispatcher",
          "type": "->"
        },
        {
          "file": "/var/www/html/lib/private/EventDispatcher/EventDispatcher.php",
          "line": 88,
          "function": "dispatch",
          "class": "Symfony\\Component\\EventDispatcher\\EventDispatcher",
          "type": "->"
        },
        {
          "file": "/var/www/html/apps/mail/lib/Service/Sync/ImapToDbSynchronizer.php",
          "line": 380,
          "function": "dispatch",
          "class": "OC\\EventDispatcher\\EventDispatcher",
          "type": "->"
        },
        {
          "file": "/var/www/html/apps/mail/lib/Service/Sync/ImapToDbSynchronizer.php",
          "line": 230,
          "function": "runPartialSync",
          "class": "OCA\\Mail\\Service\\Sync\\ImapToDbSynchronizer",
          "type": "->"
        },
        {
          "file": "/var/www/html/apps/mail/lib/Service/Sync/ImapToDbSynchronizer.php",
          "line": 135,
          "function": "sync",
          "class": "OCA\\Mail\\Service\\Sync\\ImapToDbSynchronizer",
          "type": "->"
        },
        {
          "file": "/var/www/html/apps/mail/lib/BackgroundJob/SyncJob.php",
          "line": 109,
          "function": "syncAccount",
          "class": "OCA\\Mail\\Service\\Sync\\ImapToDbSynchronizer",
          "type": "->"
        },
        {
          "file": "/var/www/html/lib/public/BackgroundJob/Job.php",
          "line": 79,
          "function": "run",
          "class": "OCA\\Mail\\BackgroundJob\\SyncJob",
          "type": "->"
        },
        {
          "file": "/var/www/html/lib/public/BackgroundJob/TimedJob.php",
          "line": 95,
          "function": "execute",
          "class": "OCP\\BackgroundJob\\Job",
          "type": "->"
        },
        {
          "file": "/var/www/html/cron.php",
          "line": 150,
          "function": "execute",
          "class": "OCP\\BackgroundJob\\TimedJob",
          "type": "->"
        }
      ],
      "File": "/var/www/html/apps/suspicious_login/vendor/rubix/ml/src/Specifications/DatasetHasDimensionality.php",
      "Line": 64
    },
    "CustomMessage": "Cron mail sync failed for account 65"
  },
  "id": "623a30d26bda1"
}

Note at the end that the DatasetHasDimensionality seems to be loaded from another app, so there might be a different version?

      "File": "/var/www/html/apps/suspicious_login/vendor/rubix/ml/src/Specifications/DatasetHasDimensionality.php",
      "Line": 64

Mail app version

1.11.7

Mailserver or service

mx.nc.c

Operating system

Ubuntu

PHP engine version

PHP 7.4

Web server

Apache (supported)

Database

MariaDB

Additional info

suspicious_login: 4.1.0

Start with apps/mail/lib/Service/Classification/ImportanceClassifier.php and apps/mail/lib/Service/Sync/ImapToDbSynchronizer.php, following the reported calls at lines 327 and 249. Compare the classification path with the suspicious_login Rubix ML dependency shown in the trace, then reproduce through cron mail sync. Done means synchronization no longer logs the dimensionality error for affected accounts.