Mage2\Catalog\Models\Product::getAttribute PHP Method

    public function getAttribute($key)
    {
        if (isset($this->attributes[$key])) {
            return $this->attributes[$key];
        }
        //
        if ($key == 'website_id') {
            $websites = $this->websites()->get()->pluck('id');
            return $websites->all();
        }
        if ($key == 'price') {
            return $this->getPrice();
        }
        //
        if ($key == 'category_id') {
            $categories = $this->categories()->get()->pluck('id');
            return $categories->all();
        }
        if ($key == 'reviews') {
            return $this->reviews()->get();
        }
        $value = null;
        //$cacheKey = ProductAttribute::class . "_" . $key;
        //if(Cache::has($cacheKey)) {
        //    $productAttribute = Cache::get($cacheKey);
        //} else {
        $productAttribute = ProductAttribute::where('identifier', '=', $key)->get()->first();
        //Cache::put($cacheKey , $productAttribute, $minute = 100);
        //}
        if (null == $productAttribute) {
            return;
        }
        switch ($productAttribute->type) {
            case 'VARCHAR':
                $value = $this->_getProductVarcharValue($productAttribute);
                break;
            case 'INTEGER':
                $value = $this->_getProductIntegerValue($productAttribute);
                break;
            case 'FLOAT':
                $value = $this->_getProductFloatValue($productAttribute);
                break;
            case 'TEXT':
                $value = $this->_getProductTextValue($productAttribute);
                break;
            case 'DATETIME':
                $value = $this->_getProductdatetimeValue($productAttribute);
                break;
            default:
                break;
        }
        return $value;
    }