Dear developers,

I have to update an external database table (with the date of course completion) every time a student complete a course. 

The best idea I found is to write a local plugin with an observer to the event \core\event\coursecompletion.

In the callback function I wrote a procedure to update an external database. 

When a student completes a course the event is fired but the external database is not updated. No error (syntax or db) is raised and I'm no able to check or modify code. 

I wrote the hook in local_plugin\db\events.php and the callback function in local_plugin\classes\observer.php 

Any idea of alternative and better solution ?

Thanks.