Visit <yoursite>/admin/settings.php?section=managelogging and enable the 'Standard log' and disable the 'Legacy log'. Visit <yoursite>/admin/settings.php?section=optionalsubsystems and enable completion tracking. Visit a course and enable completion tracking. Create an activity that has 'Completion tracking' set to 'Show activity as complete when conditions are met' and check 'Require view'. Enrol a user into a course. Visit the course as the student and view the activity. As an administration visit "<yoursite>/report/log/index.php" and view the 'Site logs'. Ensure there is only one 'Course module completion updated' event for that user.