Issue
This is the controller i have so far created:
@Controller
public class DownloadController
{
@GetMapping(path = "/download")
public ResponseEntity<Resource> download(
@RequestParam(value = "file", required = true, defaultValue = "") String param)
{
if (!param.equals("win") && !param.equals("linux") && !param.equals("mac"))
{
return null;
}
HttpHeaders header = new HttpHeaders();
header.add(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + param + ".zip");
header.add("Cache-Control", "no-cache, no-store, must-revalidate");
header.add("Pragma", "no-cache");
header.add("Expires", "0");
File file = new File("/dl/" + param + ".zip");
System.out.println("File exists: " + file.isFile() + "path: " + file.getPath()); // <- returns false and path: \dl\{param}.zip
InputStreamResource isr;
try
{
isr = new InputStreamResource(new FileInputStream(new File("/dl/" + param + ".zip")));
return ResponseEntity.ok().headers(header).contentLength(file.length())
.contentType(MediaType.APPLICATION_OCTET_STREAM).body(isr);
} catch (FileNotFoundException e)
{
return null;
}
}
}
Structure:
I'd like to provide files for download, which are in a folder as shown in structure.
I am doing it this way, because files provided for download might change and I do not want to re-deploy application. However files are not found.
Solution
Use below code for fetch resource files from your storage
private final Path root = Paths.get("dl");
public Resource load(String filename) {
try {
Path file = root.resolve(filename);
Resource resource = new UrlResource(file.toUri());
if (resource.exists() || resource.isReadable()) {
return resource;
} else {
throw new RuntimeException("Could not read the file!");
}
} catch ( MalformedURLException e) {
throw new RuntimeException("Error: " + e.getMessage());
}
}
Also use this code to send file through the rest call. (Implement in the controller)
@GetMapping("/fetch/{filename:.+}")
@ResponseBody
public ResponseEntity<Resource> getFile( @PathVariable String filename )
{
Resource file = load( filename );
return ResponseEntity.ok()
.header( HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + file.getFilename() + "\"" ).body( file );
}
Answered By - Chamikara Samarasekara
Answer Checked By - Dawn Plyler (JavaFixing Volunteer)
