Uploader.php

<?php
namespace app\models;
use Yii;
use yii\base\Model;
use yii\web\UploadedFile;
class Uploader extends Model
{
    public $img;
    public function rules()
    {
        return [
            [['img'], 'file', 'skipOnEmpty' => false, 'extensions' => 'png, jpg, jpeg'],
        ];
    }
    public static function uld() {
        $model = new self;
        $model->img = UploadedFile::getInstanceByName('upload');
        if (!$model->validate()) $message = $model->errors;
        $filename = date('d.m.Y_').rand(0, PHP_INT_MAX).'.'.$model->img->extension;
        $path_dir = Yii::getAlias('@webroot/img/editor/');
        
        if (!is_dir($path_dir)) mkdir($path_dir);
        $full_path = $path_dir.$filename;
        $link = Yii::getAlias('@web/img/editor/');
        if(@$model->img->saveAs($full_path)){
            $message = "Файл загружен";
        } else $message = 'Не удалось сохранить файл(ы). Не найденный путь: '.$full_path;
        $callback = $_REQUEST['CKEditorFuncNum'];
        echo '<script type="text/javascript">window.parent.CKEDITOR.tools.callFunction("'.$callback.'", "'.$link.$filename.'", "'.$message.'" );</script>';
    } 
}