[OJS] Usage stats are not visible


I am using the OJS, and after a moment here, the usage statistics stopped working, and are no longer displayed in the new articles that are published.

The following message is displayed Download data is not yet available.


And as you can see in the following image, after September 1 I have no statistics


Hi there, may be this thread of some help
Article statistics, Metrics stopped updating

Hi @blmirza,

What happens is that there are no files in other folders, all the files are in the archive folder, but there are only files until September 2nd. From then on, no statistics were recorded again. I don’t know what could have happened.

Hi @asmecher,

Something happened on the platform, since the log for that day is only until 15:28, there the statistics record stopped. I don’t know what I can do to fix this.


Hi again,

What are usage statistics log?
Kindly also check if the option of scheduled task is kept on on your config.inc.php file. I hope acron plugin is also enabled

Hi @blmirza,

The scheduled tasks are enabled and the acron module as well, and what I am saying is that I do not know what could have passed that date, since the logs files were not generated again and it was not inserted in the metrics table from that date.


Hi @asmecher, @ctgraham, @blmirza

Who can really help me with this problem we have, since these metrics are very important to us, and as I told you since September 2, the metrics table of the database was not registered again, nor in the usageStats folder.

Hi, @asmecher

I get an error in the plugins, when trying to generate the report from PKP Usage statistics report, a page with a 500 error appears, and in the php logs, the following error is displayed:

 [Fri Sep 18 20:34:11.617139 2020] [php7:error] [pid 9112] [client] PHP Fatal error:  Uncaught Error: [] operator not supported for strings in /var/www/html/xxxxxxxx/classes/statistics/MetricsDAO.inc.php:34\nStack trace:\n#0 /var/www/html/xxxxxxxx/plugins/generic/usageStats/PKPUsageStatsReportPlugin.inc.php(84): MetricsDAO->getMetrics('ojs::counter', Array, 'a:1:{s:10:"cont...', 'a:1:{s:5:"month...', NULL)\n#1 /var/www/html/xxxxxxxx/plugins/generic/usageStats/OJSUsageStatsReportPlugin.inc.php(32): PKPUsageStatsReportPlugin->getMetrics('ojs::counter', Array, 'a:1:{s:10:"cont...', 'a:1:{s:5:"month...', NULL)\n#2 /var/www/html/xxxxxxxx/lib/pkp/pages/management/PKPToolsHandler.inc.php(208): OJSUsageStatsReportPlugin->getMetrics('ojs::counter', Array, 'a:1:{s:10:"cont...', 'a:1:{s:5:"month...')\n#3 /var/www/html/xxxxxxxx/lib/pkp/pages/management/PKPToolsHandler.inc.php(64): PKPToolsHandler->generateReport(Array, Object(Request))\n#4 /var/www/html/xxxxxxxx/lib/pkp/classes/core/PKPRouter.inc.php(390): PKPT in /var/www/html/xxxxxxxx/classes/statistics/MetricsDAO.inc.php on line 34, referer: