Fix Possible Null value in $haystack during call to str_starts_with

[ghost]

Summary

Resolves error getting logged for a null value in $haystack for a call to str_starts_with. Since $file->getMimetype() can return null, we need to check for a null value first.

TODO

• ...

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

[provokateurin]

\OC\Files\Node\Node::getMimeType can't return null according to the docs. If there is any implementation that does, then it should be fixed instead. Can you please give some pointers on how you discovered this problem?

[ghost]

\OC\Files\Node\Node::getMimeType can't return null according to the docs. If there is any implementation that does, then it should be fixed instead. Can you please give some pointers on how you discovered this problem?

Can't but does. Ran into the following error when adding new files to a fresh install.

{
  "reqId": "t1h99RQmybeZaXEk6yyD",
  "level": 3,
  "time": "2025-10-05T05:25:09+00:00",
  "remoteAddr": "",
  "user": "--",
  "app": "core",
  "method": "",
  "url": "--",
  "message": "Error while running background job OC\\FilesMetadata\\Job\\UpdateSingleMetadata (id: 13881, arguments: [\"user\",26966])",
  "userAgent": "--",
  "version": "31.0.9.1",
  "exception": {
    "Exception": "TypeError",
    "Message": "str_starts_with(): Argument #1 ($haystack) must be of type string, null given",
    "Code": 0,
    "Trace": [
      {
        "file": "/var/www/html/lib/private/Blurhash/Listener/GenerateBlurhashMetadata.php",
        "line": 67,
        "function": "str_starts_with",
        "args": [
          null,
          "image/"
        ]
      },
      {
        "file": "/var/www/html/lib/private/EventDispatcher/ServiceEventListener.php",
        "line": 68,
        "function": "handle",
        "class": "OC\\Blurhash\\Listener\\GenerateBlurhashMetadata",
        "type": "->",
        "args": [
          {
            "__class__": "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent"
          }
        ]
      },
      {
        "file": "/var/www/html/3rdparty/symfony/event-dispatcher/EventDispatcher.php",
        "line": 220,
        "function": "__invoke",
        "class": "OC\\EventDispatcher\\ServiceEventListener",
        "type": "->",
        "args": [
          {
            "__class__": "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent"
          },
          "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent",
          {
            "__class__": "Symfony\\Component\\EventDispatcher\\EventDispatcher"
          }
        ]
      },
      {
        "file": "/var/www/html/3rdparty/symfony/event-dispatcher/EventDispatcher.php",
        "line": 56,
        "function": "callListeners",
        "class": "Symfony\\Component\\EventDispatcher\\EventDispatcher",
        "type": "->",
        "args": [
          [
            {
              "__class__": "Closure"
            }
          ],
          "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent",
          {
            "__class__": "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent"
          }
        ]
      },
      {
        "file": "/var/www/html/lib/private/EventDispatcher/EventDispatcher.php",
        "line": 67,
        "function": "dispatch",
        "class": "Symfony\\Component\\EventDispatcher\\EventDispatcher",
        "type": "->",
        "args": [
          {
            "__class__": "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent"
          },
          "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent"
        ]
      },
      {
        "file": "/var/www/html/lib/private/EventDispatcher/EventDispatcher.php",
        "line": 79,
        "function": "dispatch",
        "class": "OC\\EventDispatcher\\EventDispatcher",
        "type": "->",
        "args": [
          "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent",
          {
            "__class__": "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent"
          }
        ]
      },
      {
        "file": "/var/www/html/lib/private/FilesMetadata/FilesMetadataManager.php",
        "line": 100,
        "function": "dispatchTyped",
        "class": "OC\\EventDispatcher\\EventDispatcher",
        "type": "->",
        "args": [
          {
            "__class__": "OCP\\FilesMetadata\\Event\\MetadataBackgroundEvent"
          }
        ]
      },
      {
        "file": "/var/www/html/lib/private/FilesMetadata/Job/UpdateSingleMetadata.php",
        "line": 43,
        "function": "refreshMetadata",
        "class": "OC\\FilesMetadata\\FilesMetadataManager",
        "type": "->",
        "args": [
          {
            "__class__": "OC\\Files\\Node\\File"
          },
          2
        ]
      },
      {
        "file": "/var/www/html/lib/public/BackgroundJob/Job.php",
        "line": 61,
        "function": "run",
        "class": "OC\\FilesMetadata\\Job\\UpdateSingleMetadata",
        "type": "->",
        "args": [
          [
            "user",
            26966
          ]
        ]
      },
      {
        "file": "/var/www/html/lib/public/BackgroundJob/QueuedJob.php",
        "line": 43,
        "function": "start",
        "class": "OCP\\BackgroundJob\\Job",
        "type": "->",
        "args": [
          {
            "__class__": "OC\\BackgroundJob\\JobList"
          }
        ]
      },
      {
        "file": "/var/www/html/lib/public/BackgroundJob/QueuedJob.php",
        "line": 29,
        "function": "start",
        "class": "OCP\\BackgroundJob\\QueuedJob",
        "type": "->",
        "args": [
          {
            "__class__": "OC\\BackgroundJob\\JobList"
          }
        ]
      },
      {
        "file": "/var/www/html/cron.php",
        "line": 170,
        "function": "execute",
        "class": "OCP\\BackgroundJob\\QueuedJob",
        "type": "->",
        "args": [
          {
            "__class__": "OC\\BackgroundJob\\JobList"
          }
        ]
      }
    ],
    "File": "/var/www/html/lib/private/Blurhash/Listener/GenerateBlurhashMetadata.php",
    "Line": 67,
    "message": "Error while running background job OC\\FilesMetadata\\Job\\UpdateSingleMetadata (id: 13881, arguments: [\"user\",26966])",
    "exception": {},
    "CustomMessage": "Error while running background job OC\\FilesMetadata\\Job\\UpdateSingleMetadata (id: 13881, arguments: [\"user\",26966])"
  }
}

[provokateurin]

Ok, then we'll have to check where that came from.

[provokateurin]

@lps-rocks I found some places where this problem could originate from. Can you run occ info:file 26966 and post the output here? It might give some pointers about the specific root cause.

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