Merge pull request #13791 from SORMAS-Foundation/bugfix-13433-empty-file-downloading-issue

fixed the empty PDF file downloading issue

Author: KarnaiahPesula

sormas-ui/src/main/java/de/symeda/sormas/ui/externalmessage/ExternalMessageController.java

@@ -16,6 +16,7 @@
 
 import static de.symeda.sormas.ui.externalmessage.processing.ExternalMessageProcessingUIHelper.showAlreadyProcessedPopup;
 
+import java.nio.charset.StandardCharsets;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.List;
@@ -417,6 +418,28 @@ private HorizontalLayout getExternalMessageButtonsPanel(ExternalMessageDto exter
 		return buttonsPanel;
 	}
 
+	/**
+	 * Downloads the attachment of an external message as byte array.
+	 * 
+	 * @param externalMessageUuid
+	 *            the UUID of the external message
+	 * @return the attachment as byte array wrapped in an Optional
+	 */
+	public Optional<byte[]> downloadExternalMessageAttachment(String externalMessageUuid) {
+
+		if (StringUtils.isBlank(externalMessageUuid)) {
+			return Optional.empty();
+		}
+
+		ExternalMessageDto externalMessageDto = FacadeProvider.getExternalMessageFacade().getByUuid(externalMessageUuid);
+
+		return Optional.ofNullable(externalMessageDto.getExternalMessageDetails()).map(details -> details.getBytes(StandardCharsets.UTF_8));
+	}
+
+	/**
+	 * Converts the external message to PDF format.
+	 * Keeping this method for future use cases.
+	 */
 	public Optional<byte[]> convertToPDF(String externalMessageUuid) {
 
 		ExternalMessageDto externalMessageDto = FacadeProvider.getExternalMessageFacade().getByUuid(externalMessageUuid);

sormas-ui/src/main/java/de/symeda/sormas/ui/externalmessage/ExternalMessageGrid.java

@@ -70,6 +70,7 @@ public class ExternalMessageGrid extends FilteredGrid<ExternalMessageIndexDto, E
 
 	private static final String PLACEHOLDER_SPACE = String.join("", Collections.nCopies(35, "&nbsp"));
 	private static final String PDF_FILENAME_FORMAT = "sormas_lab_message_%s_%s.pdf";
+	private static final String XML_FILENAME_FORMAT = "sormas_lab_message_%s_%s.xml";
 
 	private DataProviderListener<ExternalMessageIndexDto> dataProviderListener;
 
@@ -230,12 +231,15 @@ private Button buildDownloadButton(ExternalMessageIndexDto labMessage) {
 		Button downloadButton = new Button(VaadinIcons.DOWNLOAD);
 		downloadButton.setDescription(I18nProperties.getString(Strings.headingExternalMessageDownload));
 		final String fileName =
-			String.format(PDF_FILENAME_FORMAT, DataHelper.getShortUuid(labMessage.getUuid()), DateHelper.formatDateForExport(new Date()));
+			String.format(XML_FILENAME_FORMAT, DataHelper.getShortUuid(labMessage.getUuid()), DateHelper.formatDateForExport(new Date()));
 
 		StreamResource streamResource = new StreamResource(
-			() -> ControllerProvider.getExternalMessageController().convertToPDF(labMessage.getUuid()).map(ByteArrayInputStream::new).orElse(null),
+			() -> ControllerProvider.getExternalMessageController()
+				.downloadExternalMessageAttachment(labMessage.getUuid())
+				.map(ByteArrayInputStream::new)
+				.orElse(null),
 			fileName);
-		streamResource.setMIMEType("text/pdf");
+		streamResource.setMIMEType("application/xml");
 
 		FileDownloader fileDownloader = new FileDownloader(streamResource);
 		fileDownloader.extend(downloadButton);