Alamofire download file with progress issue - php

Question

I want to download a file from server with progress. Here is the code I've tried:
let destination: (NSURL, NSHTTPURLResponse) -> (NSURL) = {
(temporaryURL, response) in
if let directoryURL = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)[0] as? NSURL {
let path = directoryURL.URLByAppendingPathComponent(response.suggestedFilename!)
return path
}
return temporaryURL
}
Alamofire.download(.GET, fileUrls[button.tag], destination: destination)
.progress { _, totalBytesRead, totalBytesExpectedToRead in
dispatch_async(dispatch_get_main_queue()) {
println("\(Float(totalBytesRead)) - \(Float(totalBytesExpectedToRead))")
if totalBytesRead == totalBytesExpectedToRead {
println("******************************")
println("finished")
println("******************************")
}
}
}
.response { (_, _, data, error) in
println(data)
println(error)
}
But totalBytesExpectedToRead is always -1. I've searched this issue and found that Content-Length on server side isn't set.
I've tried to set it but it doesn't seem to work:
$attachment_location = $_GET["filepath"];
if (file_exists($attachment_location)) {
header('Content-Description: File Transfer');
header('Content-Type:' . mime_content_type($attachment_location));
header('Content-Disposition: attachment; filename='.basename($attachment_location));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($attachment_location));
readfile($attachment_location);
die();
} else {
die("Error: File not found.");
}
Can some one tell me what I'm doing wrong? Thanks.

Answer 1

Solved by changing the code to this:
$attachment_location = $_GET["filepath"];
if (file_exists($attachment_location)) {
header('Content-Description: File Transfer');
header('Content-Type:' . mime_content_type($attachment_location));
header('Content-Disposition: attachment; filename='.basename($attachment_location));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Encoding: chunked');
header('Content-Length: ' . filesize($attachment_location), true);
readfile($attachment_location);
die();
} else {
die("Error: File not found.");
}