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Spring Boot FileLİst download zip

in spring boot project, I want to download all the files of he user into a single zip.
#GetMapping("/allFilePerson/{personId}")
public ResponseEntity<HttpStatus> allFilePerson(#PathVariable(value = "personId") Integer personId) {
List<file> fileList=service.findByFileId(personId);
....
}
This code single file download.But convert to fileList zip or rar.
#RequestMapping("/downloadFile/{fileId}")
public ResponseEntity<HttpStatus> handleFileDownloadPage(HttpServletRequest request, HttpServletResponse response, #PathVariable(value = "fileId") Integer fileId) throws IOException, Exception {
File file = service.getFile(fileId);
ServletOutputStream out = response.getOutputStream();
InputStream stream = null;
stream = new FileInputStream(file.getFilePath());
//write the file to the file specified
int bytesRead = 0;
byte[] buffer = new byte[8192];
response.setContentType("application/octet-stream");
response.setCharacterEncoding("UTF-8");
response.setHeader("Content-Disposition", String.format(" attachment; filename=\"%s\"", file.getFileName()));
while ((bytesRead = stream.read(buffer, 0, 8192)) != -1) {
out.write(buffer, 0, bytesRead);
}
out.flush();
out.close();
return ResponseEntity.ok(HttpStatus.OK);
}

Java zip files from streams instantly without using byte[]

I want to compress multiples files into a zip files, I'm dealing with big files, and then download them into the client, for the moment I'm using this:
#RequestMapping(value = "/download", method = RequestMethod.GET, produces = "application/zip")
public ResponseEntity <StreamingResponseBody> getFile() throws Exception {
File zippedFile = new File("test.zip");
FileOutputStream fos = new FileOutputStream(zippedFile);
ZipOutputStream zos = new ZipOutputStream(fos);
InputStream[] streams = getStreamsFromAzure();
for (InputStream stream: streams) {
addToZipFile(zos, stream);
}
final InputStream fecFile = new FileInputStream(zippedFile);
Long fileLength = zippedFile.length();
StreamingResponseBody stream = outputStream - >
readAndWrite(fecFile, outputStream);
return ResponseEntity.ok()
.header(HttpHeaders.ACCESS_CONTROL_EXPOSE_HEADERS, HttpHeaders.CONTENT_DISPOSITION)
.header(HttpHeaders.CONTENT_DISPOSITION, "attachment;filename=" + "download.zip")
.contentLength(fileLength)
.contentType(MediaType.parseMediaType("application/zip"))
.body(stream);
}
private void addToZipFile(ZipOutputStream zos, InputStream fis) throws IOException {
ZipEntry zipEntry = new ZipEntry(generateFileName());
zos.putNextEntry(zipEntry);
byte[] bytes = new byte[1024];
int length;
while ((length = fis.read(bytes)) >= 0) {
zos.write(bytes, 0, length);
}
zos.closeEntry();
fis.close();
}
This take a lot of time before all files are zipped and then the downloading start, and for large files this kan take a lot of time, this is the line responsible for the delay:
while ((length = fis.read(bytes)) >= 0) {
zos.write(bytes, 0, length);
}
So is there a way to download files immediately while their being zipped ?

Try this instead. Rather than using the ZipOutputStream to wrap a FileOutputStream, writing your zip to a file, then copying it to the client output stream, instead just use the ZipOutputStream to wrap the client output stream so that when you add zip entries and data it goes directly to the client. If you want to also store it to a file on the server then you can make your ZipOutputStream write to a split output stream, to write both locations at once.
#RequestMapping(value = "/download", method = RequestMethod.GET, produces = "application/zip")
public ResponseEntity<StreamingResponseBody> getFile() throws Exception {
InputStream[] streamsToZip = getStreamsFromAzure();
// You could cache already created zip files, maybe something like this:
// String[] pathsOfResourcesToZip = getPathsFromAzure();
// String zipId = getZipId(pathsOfResourcesToZip);
// if(isZipExist(zipId))
// // return that zip file
// else do the following
StreamingResponseBody streamResponse = clientOut -> {
FileOutputStream zipFileOut = new FileOutputStream("test.zip");
ZipOutputStream zos = new ZipOutputStream(new SplitOutputStream(clientOut, zipFileOut));
for (InputStream in : streamsToZip) {
addToZipFile(zos, in);
}
};
return ResponseEntity.ok()
.header(HttpHeaders.ACCESS_CONTROL_EXPOSE_HEADERS, HttpHeaders.CONTENT_DISPOSITION)
.header(HttpHeaders.CONTENT_DISPOSITION, "attachment;filename=" + "download.zip")
.contentType(MediaType.parseMediaType("application/zip")).body(streamResponse);
}
private void addToZipFile(ZipOutputStream zos, InputStream fis) throws IOException {
ZipEntry zipEntry = new ZipEntry(generateFileName());
zos.putNextEntry(zipEntry);
byte[] bytes = new byte[1024];
int length;
while ((length = fis.read(bytes)) >= 0) {
zos.write(bytes, 0, length);
}
zos.closeEntry();
fis.close();
}
public static class SplitOutputStream extends OutputStream {
private final OutputStream out1;
private final OutputStream out2;
public SplitOutputStream(OutputStream out1, OutputStream out2) {
this.out1 = out1;
this.out2 = out2;
}
#Override public void write(int b) throws IOException {
out1.write(b);
out2.write(b);
}
#Override public void write(byte b[]) throws IOException {
out1.write(b);
out2.write(b);
}
#Override public void write(byte b[], int off, int len) throws IOException {
out1.write(b, off, len);
out2.write(b, off, len);
}
#Override public void flush() throws IOException {
out1.flush();
out2.flush();
}
/** Closes all the streams. If there was an IOException this throws the first one. */
#Override public void close() throws IOException {
IOException ioException = null;
for (OutputStream o : new OutputStream[] {
out1,
out2 }) {
try {
o.close();
} catch (IOException e) {
if (ioException == null) {
ioException = e;
}
}
}
if (ioException != null) {
throw ioException;
}
}
}
For the first request for a set of resources to be zipped you wont know the size that the resulting zip file will be so you can't send the length along with the response since you are streaming the file as it is zipped.
But if you expect there to be repeated requests for the same set of resources to be zipped, then you can cache your zip files and simply return them on any subsequent requests; You will also know the length of the cached zip file so you can send that in the response as well.
If you want to do this then you will have to be able to consistently create the same identifier for each combination of the resources to be zipped, so that you can check if those resources were already zipped and return the cached file if they were. You might be able to could sort the ids (maybe full paths) of the resources that will be zipped and concatenate them to create an id for the zip file.

Spring boot: Download zipped large files while they are being processed on the server

In my app I'm zipping and then downloading larges files, the files are located in azure, so I read the files from a stream and then zip them one after another, so I can dowload the zip file after all files has been zipped, here's my code:
#RequestMapping(value = "{analyseId}/download", method = RequestMethod.GET, produces = "application/zip")
public ResponseEntity<Resource> download(#PathVariable List<String> paths) throws IOException {
String zipFileName = "zipFiles.zip";
File zipFile = new File(zipFileName);
FileOutputStream fos = new FileOutputStream(zipFile);
ZipOutputStream zos = new ZipOutputStream(fos);
for (String path : paths) {
InputStream fis = azureDataLakeStoreService.readFile(path);
addToZipFile(path , zos, fis);
}
zos.close();
fos.close();
BufferedInputStream zipFileInputStream = new BufferedInputStream(new FileInputStream(zipFile.getAbsolutePath()));
InputStreamResource resource = new InputStreamResource(zipFileInputStream);
zipFile.delete();
return ResponseEntity.ok()
.header(HttpHeaders.ACCESS_CONTROL_EXPOSE_HEADERS, HttpHeaders.CONTENT_DISPOSITION)
.header(HttpHeaders.CONTENT_DISPOSITION, "attachment;filename=" + zipFileName)
.contentType(MediaType.parseMediaType("application/octet-stream"))
.body(resource);
}
private static void addToZipFile(String path, ZipOutputStream zos, InputStream fis) throws IOException {
ZipEntry zipEntry = new ZipEntry(FilenameUtils.getName(path));
zos.putNextEntry(zipEntry);
byte[] bytes = new byte[1024];
int length;
while ((length = fis.read(bytes)) >= 0) {
zos.write(bytes, 0, length);
}
zos.closeEntry();
fis.close();
}
However on azure the request time out is set to 230 sec, and cannot be changed, however for big files it takes more than that to load and then zip the files on the server, so the connection with the client will be lost meanwhile.
So my question is since I'm getting the data from a stream, can we do all these operations simultaneously, means getting the stream and download it as the same time and not waiting till getting the whole file, or if there any other idea can any body share it here please.
Thanks.

The answer is to not download the file to the server and then send it to the client but streaming it to the client directly here's the code
#RequestMapping(value = "/download", method = RequestMethod.GET)
public StreamingResponseBody download(#PathVariable String path) throws IOException {
final InputStream fecFile = azureDataLakeStoreService.readFile(path);
return (os) -> {
readAndWrite(fecFile, os);
};
}
private void readAndWrite(final InputStream is, OutputStream os)
throws IOException {
byte[] data = new byte[2048];
int read = 0;
while ((read = is.read(data)) >= 0) {
os.write(data, 0, read);
}
os.flush();
}
I also added this configuration to ApplicationInit:
#Configuration
public static class WebConfig extends WebMvcConfigurerAdapter {
#Override
public void configureAsyncSupport(AsyncSupportConfigurer configurer) {
configurer.setDefaultTimeout(-1);
configurer.setTaskExecutor(asyncTaskExecutor());
}
#Bean
public AsyncTaskExecutor asyncTaskExecutor() {
return new SimpleAsyncTaskExecutor("async");
}
}

Spring REST - Damaged/Blank File being downloaded

I am trying to create a endpoint to render/serve PDF file.
I have gone through the following links to build the API, but still facing some issues.
link 1
link 2
Following is my code :
byte[] targetArray = null;
InputStream is = null;
InputStream objectData = object.getObjectContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(objectData));
char[] charArray = new char[8 * 1024];
StringBuilder builder = new StringBuilder();
int numCharsRead;
while ((numCharsRead = reader.read(charArray, 0, charArray.length)) != -1) {
builder.append(charArray, 0, numCharsRead);
}
reader.close();
objectData.close();
object.close();
targetArray = builder.toString().getBytes();
is = new ByteArrayInputStream(targetArray);
return ResponseEntity.ok().contentLength(targetArray.length).contentType(MediaType.APPLICATION_PDF)
.cacheControl(CacheControl.noCache()).header("Content-Disposition", "attachment; filename=" + "testing.pdf")
.body(new InputStreamResource(is));
When I hit my API using postman, I am able to download PDF file but the problem is it is totally blank. What might be the issue ?

There are multiple ways to download files from server, you can use ResponseEntity<InputStreamResource>, HttpServletResponse.Below are the two methods to download.
#GetMapping("/download1")
public ResponseEntity<InputStreamResource> downloadFile1() throws IOException {
File file = new File(FILE_PATH);
InputStreamResource resource = new InputStreamResource(new FileInputStream(file));
return ResponseEntity.ok()
.header(HttpHeaders.CONTENT_DISPOSITION,
"attachment;filename=" + file.getName())
.contentType(MediaType.APPLICATION_PDF).contentLength(file.length())
.body(resource);
}
OR
You can use StreamingResponseBody to download large files. In this case server writes data to OutputStream at same time Browser read data which means its parallel.
#RequestMapping(value = "downloadFile", method = RequestMethod.GET)
public StreamingResponseBody getSteamingFile(HttpServletResponse response) throws IOException {
response.setContentType("application/pdf");
response.setHeader("Content-Disposition", "attachment; filename=\"demo.pdf\"");
InputStream inputStream = new FileInputStream(new File("C:\\demo-file.pdf"));
return outputStream -> {
int nRead;
byte[] data = new byte[1024];
while ((nRead = inputStream.read(data, 0, data.length)) != -1) {
System.out.println("Writing some bytes..");
outputStream.write(data, 0, nRead);
}
};
}

You can try to use apache commons IOUtils. Why reinvent wheel :)
1. Open a connection to remote server
2. Copy the inputStream to the destination file outputStream.
public void downloadFileFromRemoteLocation(String serverlocation, File destinationFile) throws IOException
{
try (FileOutputStream fos = new FileOutputStream( destinationFile )){
URL url = new URL(serverlocation);
URLConnection connection = url.openConnection();
IOUtils.copy( connection.getInputStream(), fos);
}
}
if you want to stick to just Java then look at snippet below
try {
// Get the directory and iterate them to get file by file...
File file = new File(fileName);
if (!file.exists()) {
context.addMessage(new ErrorMessage("msg.file.notdownloaded"));
context.setForwardName("failure");
} else {
response.setContentType("APPLICATION/DOWNLOAD");
response.setHeader("Content-Disposition", "attachment"+
"filename=" + file.getName());
stream = new FileInputStream(file);
response.setContentLength(stream.available());
OutputStream os = response.getOutputStream();
os.close();
response.flushBuffer();
}
} catch (IOException e) {
e.printStackTrace();
} finally {
if (stream != null) {
try {
stream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}

ZipOutputStream.finish() and write file in a wrong directory and Tomcat

when i call .finish() and .close() for a zipOutputStream for download a zip file on a page of my webApp, it saves the content of zip file in my temp user folder ( example: c:/user/appdata/local/temp ) but i want to save this files in TomcatHome/temp.
// setting headers
response.setContentType("application/zip");
response.setStatus(HttpServletResponse.SC_OK);
response.addHeader("Content-Disposition", "attachment; filename=\"test.zip\"");
// creating byteArray stream, make it bufforable and passing this buffor to ZipOutputStream
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(byteArrayOutputStream);
ZipOutputStream zipOutputStream = new ZipOutputStream(bufferedOutputStream);
for (int i = 0; i < listIdFile.size(); i++) {
try {
FileDTO file = this.fileDAO.getFileById(listIdFile.get(i));
File fileFull = this.fileDAO.readFileFull(Integer.parseInt(file.getId()));
zipOutputStream.putNextEntry(new ZipEntry(file.getNomeFile()));
FileInputStream fileInputStream = new FileInputStream(fileFull);
IOUtils.copy(fileInputStream, zipOutputStream);
fileInputStream.close();
zipOutputStream.closeEntry();
} catch (Exception e) {
log.error(e.getMessage());
e.printStackTrace();
// return downloadDocumentoDaLocale(response, listIdFile);
}
}
if (zipOutputStream != null) {
// zipOutputStream.finish();
zipOutputStream.close();
zipOutputStream.finish();
IOUtils.closeQuietly(zipOutputStream);
}
IOUtils.closeQuietly(bufferedOutputStream);
IOUtils.closeQuietly(byteArrayOutputStream);
}
Any suggest?
Thank you