Added book search.

src/Service/FileService.php

@@ -60,7 +60,7 @@ class FileService
         $file = new File();
         $file->setFileName(trim($ebook->getClientOriginalName()));
         $file->setFileSize($ebook->getSize());
-        $file->setExtension($ebook->guessClientExtension());
+        $file->setExtension($ebook->getClientOriginalExtension());
         $file->setBook($book);
         $this->fileRepository->add($file, true);