app\models\Task::calcStartTime PHP Метод

    public static function calcStartTime($task)
    {
        $parts = json_decode($task->time_log) ?: [];
        if (count($parts)) {
            return Utils::timestampToDateTimeString($parts[0][0]);
        } else {
            return '';
        }
    }

 protected function getDatatableColumns($entityType, $hideClient)
 {
     return [['client_name', function ($model) {
         return $model->client_public_id ? link_to("clients/{$model->client_public_id}", Utils::getClientDisplayName($model)) : '';
     }, !$hideClient], ['created_at', function ($model) {
         return link_to("tasks/{$model->public_id}/edit", Task::calcStartTime($model));
     }], ['time_log', function ($model) {
         return Utils::formatTime(Task::calcDuration($model));
     }], ['description', function ($model) {
         return $model->description;
     }], ['invoice_number', function ($model) {
         return self::getStatusLabel($model);
     }]];
 }