Downloading a zip file from a folder on my web server - php

Question

I have an application that allows users to download mulitple files from a S3 bucket through an EC2 instance in one zip folder.
The process works fine, however, I would like the system to create a folder for each user when they want to download files, and then the files are downloaded to this folder and then put in a zip folder, within the user's folder, and then this zip folder is downloaded.
The files are downloading to this folder fine, and they are also zipping correctly, but my problem is that it is not downloading the zip file from the user's folder, and the download is showing as an empty zip file.
Below is my 'download all' code:
mkdir($userId);
$allName = $vshort . "v" . $number . "_All.zip";
$allName = str_replace(" ", "_", $allName);
if (isset($_POST['downloadAll']))
{
$zip = new ZipArchive();
$zip->open("{$userId}/{$allName}", ZipArchive::CREATE);
$s3->registerStreamWrapper();
foreach ($items as $item)
{
$fid = $item->item_file_id;
$file = ItemFile::locateId($fid);
$a = $file[0]->item_file_type;
$b = $file[0]->item_file_app;
$c = $file[0]->item_file_name;
$fileName = $a . "/" . $b . "/" . $c;
$download = $s3->getCommand('GetObject', [
'Bucket' => AWS_BUCKET,
'Key' => $fileName
]);
$streamFile = $c;
$user = User::locate($_SESSION['email']);
$uid = $user->user_id;
$cid = $user->user_company_id;
$history = new History();
$history->insert($fid, $uid, $cid);
$req = $s3->createPresignedRequest($download, '+1 minutes');
$link = (string)$req->getUri();
$stream = file_get_contents($link);
header($_SERVER["SERVER_PROTOCOL"] . " 200 OK");
header("Cache-Control: public"); // needed for internet explorer
header("Content-Type: application/'$a'");
header("Content-Disposition: attachment; filename='$c'");
file_put_contents($streamFile, $stream);
$zip->addFile($streamFile);
$downArray[] = $streamFile;
}
$zip->close();
$dLink = "https://mywebsite/" . $userId . "/" . $allName;
$size = filesize($allName);
header("Content-type: application/zip");
header("Content-Disposition: attachment; filename=$allName");
header("Content-length: " . $size);
header("Expires: 0");
ob_end_clean();
stream_context_set_default([
'ssl' => [
'verify_peer' => false,
'verify_peer_name' => false,
]
]);
readfile($dLink);
unlink($allName);
foreach ($downArray as $down)
{
unlink($down);
}
}
I have a feeling it is something to do with my headers but I'm not sure, any help will be greatly appreciated.
NOTE: I will be deleting the folder once the user has exited the page.
Below is what I am seeing on the web server
The folder '6' is the user id for the user in question

Answer 1

You appear to be calling readfile() on your download link ($dLink), which would serve the file throught HTTP. You probably meant to call readfile on $allName, the filesystem path of the same file. My guess is that your http request to $dLink is failing somehow. Also, you mkdir($userId), but never use that directory.
Apart from that, it seems your $allName variable contains the basename of the zipfile (i.e 'myzip-v-20_ALL.zip'). I would recommend opening your zipfile to a full path to your data directory, so you keep filesystem and http paths separate.
$allNameFilesystem = "{$userId}/{$allName}";
$allNameHttp = "https://mywebsite/{$userId}{$allName}";
// ...
$zip->open($allNameFilesystem, ZipArchive::CREATE);
// ...
// The download link is $allNameHttp
That is, if you actually need the http path. In this case, if you change readfile to use the filesystem path, you really don't use the http path anymore in your code.