[Solved] PDF download - PHP Fatal error - Application::getApplication() returns null

I am running an OJS installation (Version on Linux (Red Hat Enterprise Linux Server release 6.7) in Apache 2.2.15.

I am seeing these lines in my error_log:
PHP Fatal error: Call to a member function getRequest() on a non-object in .../plugins/generic/usageStats/UsageStatsPlugin.inc.php on line 223

Doing some research I could narrow this down to the fact that
returns null whenever a PDF is downloaded. The hookName is FileManager::downloadFileFinished
whenever that happens.

Is this a bug?
Is my installation somehow borked?


I took a deeper look and found that in FileManager::downloadFile() there is a call to Registry::clear() before the postDownload-Hooks get called.

Application::getApplication() calls Registry::get() which in this case can’t return anything as the registry is cleared…

So this is a bug!?
Or am I missing something?


I think this is reported in GitHub Issue 847, and fixed in 2.4.8. Can you try upgrading and confirm whether it resolves the problem?

1 Like

Thanks, Clinton!
Yes, upgrading to 2.4.8 fixed the problem. Article downloads are logged now and those “Fatal errors” are gone.
I searched this forum but forgot to search the github issues. Next time I will look there as well.

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