isTopSeller example

'supplierMedia' => $product->getManufacturer()->getCoverMedia() ? $this->convertMediaStruct($product->getManufacturer()->getCoverMedia()) : null,
            ];

            $data = array_merge($data, $manufacturer);
            $data['supplier_attributes'] = $product->getManufacturer()->getAttributes();
        }

        $marketing = $product->getAttribute('marketing');
        if ($marketing instanceof MarketingAttribute) {
            $data['newArticle'] = $marketing->isNew();
            $data['sUpcoming'] = $marketing->comingSoon();
            $data['topseller'] = $marketing->isTopSeller();
        }

        $today = new DateTime();
        if ($product->getReleaseDate() && $product->getReleaseDate() > $today) {
            $data['sReleasedate'] = $this->dateToString($product->getReleaseDate());
            $data['sReleaseDate'] = $data['sReleasedate'];
        }

        return $this->eventManager->filter('Legacy_Struct_Converter_List_Product_Data', $data, [
            'product' => $product,
        ]);
    }