通过http发布的文件下载将返回zip文件内容

Question

I could see many related topics, but I have a specific problem. I am using spring boot controller to download a zip file. I am able to download the file when it is http verb get, but as I have to pass a big json payload I changed to post. Since then instead of downloading it as file it is responding the contents of the file with some ascii characters. Below is the method in controller for downloading the file.

@ApiResponses(value = { @ApiResponse(code = 404, message = "file could not be found"),
        @ApiResponse(code = 200, message = "File was created sucessfully") })
@PostMapping(path="/download-file/1.0", produces="application/zip")
public ResponseEntity<InputStreamResource> downloadFile(
        @ApiParam(value = "File creation contents", required = true) @RequestBody InputDetailsVO inputDetailsVO) {
    File file = null;
    InputStreamResource resource = null;
    HttpHeaders headers = new HttpHeaders();
    try {
        //Creating InputStreamResource out of zip file
        resource = new InputStreamResource(new FileInputStream(file));          
        String contentType = "application/zip";
        if (!StringUtils.isEmpty(contentType)) {
           headers.setContentType(MediaType.parseMediaType(contentType));
        }
        headers.add("Content-Disposition","attachment; filename=\""+file.getName()+"\"");
    } catch (Exception e) {
        log.error("Issue with file creation",e);

    }
    return ResponseEntity.ok()
            .contentLength(file.length())
            .contentType(MediaType
                          .parseMediaType(MediaType.APPLICATION_OCTET_STREAM_VALUE))
             .headers(headers).body(resource);
}   

Below is the response I am getting instead of file download

    PK;��N <?xml version="1.0" encoding="UTF-8"?>
<employeeDetails>
<name>Harry</name>
<age>30</30>
<email>test@test.com</test>
</employeeDetails>PK�qB�@Y;YPK;��N�qB�@Y;Yemployee details.xmlPKL�Y

Answer 1

Try like this, you can download any type of file. I assume that InputDetailsVO contains the name of the file or you can have your own logic to pick the file name. On the top of this method, you can provide swagger related annotations.

@PostMapping(value = "/download-file/1.0", produces = MediaType.APPLICATION_OCTET_STREAM_VALUE)
  public ResponseEntity<?> downloadFile(@RequestBody InputDetailsVO inputDetailsVO) {
    String dirPath = "your-location-path";
    byte[] fileBytes = null;
    try {
       String fileName = inputDetailsVO.getFileName();
      fileBytes = Files.readAllBytes(Paths.get(dirPath + fileName));
    } catch (IOException e) {
      e.printStackTrace();
    }
    return ResponseEntity.ok()
        .contentType(MediaType.APPLICATION_OCTET_STREAM)
        .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + fileName + "\"")
        .body(fileBytes);
  }

Answer 2

I also had a similar use case. I am sharing the code which had solved the issue.

  @RequestMapping(value="/download",method=RequestMethod.GET,produces="application/zip" )
        public ResponseEntity<?> download(HttpServletResponse response) throws IOException
        {
            //Some Code...

            File file = new File("F:\\Folder\\Folder\\Folder\\"+filename); 
            InputStreamResource resource2 = new InputStreamResource(new FileInputStream(file));
            response.setContentType("application/zip");
            response.setHeader("Content-Disposition", String.format("inline; filename=\"" + filename + "\""));
            response.setHeader("responseType", "arraybuffer");
            response.setHeader("Content-Length", ""+file.length());

            return new ResponseEntity<InputStreamResource>(resource2,HttpStatus.ACCEPTED);

        }