public function export()
    {
        $this->loadModel('User.Acos');
        $out = [];
        $permissions = $this->Acos->Permissions
            ->find()
            ->contain(['Acos', 'Roles'])
            ->all();

        foreach ($permissions as $permission) {
            if (!isset($out[$permission->role->slug])) {
                $out[$permission->role->slug] = [];
            }
            $out[$permission->role->slug][] = implode(
                '/',
                $this->Acos
                ->find('path', ['for' => $permission->aco->id])
                ->extract('alias')
                ->toArray()
            );
        }

        $this->title(__d('user', 'Export Permissions'));
        $this->response->body(json_encode($out, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES));
        $this->response->type('json');
        $this->response->download('permissions_' . date('Y-m-d@H:i:s-\U\TC', time()) . '.json');

        return $this->response;
    }