Fixing the export page issue, if there are a huge amount of exported items

Author: eduard13

app/code/Magento/ImportExport/Ui/DataProvider/ExportFileDataProvider.php

@@ -7,16 +7,23 @@
 
 namespace Magento\ImportExport\Ui\DataProvider;
 
+use Magento\Framework\App\ObjectManager;
 use Magento\Framework\View\Element\UiComponent\DataProvider\DataProvider;
 use Magento\Framework\Filesystem\DriverInterface;
 use Magento\Framework\App\Filesystem\DirectoryList;
 use Magento\Framework\Filesystem;
+use Magento\Framework\Filesystem\Io\File;
 
 /**
  * Data provider for export grid.
  */
 class ExportFileDataProvider extends DataProvider
 {
+    /**
+     * @var File|null
+     */
+    private $fileIO;
+
     /**
      * @var DriverInterface
      */
@@ -37,6 +44,7 @@ class ExportFileDataProvider extends DataProvider
      * @param \Magento\Framework\Api\FilterBuilder $filterBuilder
      * @param DriverInterface $file
      * @param Filesystem $filesystem
+     * @param File|null $fileIO
      * @param array $meta
      * @param array $data
      * @SuppressWarnings(PHPMD.ExcessiveParameterList)
@@ -51,6 +59,7 @@ public function __construct(
         \Magento\Framework\Api\FilterBuilder $filterBuilder,
         DriverInterface $file,
         Filesystem $filesystem,
+        File $fileIO = null,
         array $meta = [],
         array $data = []
     ) {
@@ -67,6 +76,9 @@ public function __construct(
             $meta,
             $data
         );
+
+        $this->fileIO = $fileIO ?: ObjectManager::getInstance()->get(File::class);
+        $this->request = $request;
     }
 
     /**
@@ -89,10 +101,14 @@ public function getData()
         }
         $result = [];
         foreach ($files as $file) {
-            $result['items'][]['file_name'] = basename($file);
+            $result['items'][]['file_name'] = $this->fileIO->getPathInfo($file)['basename'];
         }
 
+        $pageSize = (int) $this->request->getParam('paging')['pageSize'];
+        $pageCurrent = (int) $this->request->getParam('paging')['current'];
+        $pageOffset = ($pageCurrent - 1) * $pageSize;
         $result['totalRecords'] = count($result['items']);
+        $result['items'] = array_slice($result['items'], $pageOffset, $pageSize);
 
         return $result;
     }

app/code/Magento/ImportExport/view/adminhtml/ui_component/export_grid.xml

@@ -34,6 +34,9 @@
             </settings>
         </dataProvider>
     </dataSource>
+    <listingToolbar name="listing_top">
+        <paging name="listing_paging"/>
+    </listingToolbar>
     <columns name="export_grid_columns">
         <column name="file_name">
             <settings>