运行脚本时无法从FTP服务器自动下载文件

Question

I am attempting to write a PHP page that takes the GET variable which is a filename within the FTP and download it. However, it does not seem to work. The Function itself (ftp_get) is returning as TRUE as the echo statement is being run, however nothing else happens and there is no errors in console.

<?php  
$file = $_GET['file'];

$ftp_server = "127.0.0.1";
$ftp_user_name = "user";
$ftp_user_pass = "pass";
// set up a connection or die
$conn_id = ftp_connect($ftp_server) or die("Couldn't connect to $ftp_server"); 

// login with username and password
$login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass);

if (ftp_get($conn_id, $file, $file, FTP_BINARY)) {
    echo "Successfully written to $file\n";
} else {
    echo "There was a problem\n";
}

?>

Ideally, I would simply link them to: ftp://example.com/TestFile.txt and it would download the file for them, however, it only shows them the contents of the file in their browser rather than downloading it.

I've gone through the PHP Manual site reading the FTP functions and I do believe ftp_get is the correct one I'm suppose to be using.

Is there potentially an easier way of doing this, or is it just something I'm overlooking?

Answer 1

There are two (or maybe more) ways you can do this. You could store a copy of the file on your server like you do with ftp_get and send it to the user afterwards. Or you could download it every time.

Now you can do this using ftp commands, but there is a quicker way using readfile .
Following the first example from the readfile documentation:

// Save the file as a url
$file = "ftp://{$ftp_user_name}:{$ftp_user_pass}@{$ftp_server}" . $_GET['file'];

// Set the appropriate headers for a file transfer
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename=' . basename($file));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($file));
// and send them
ob_clean();
flush();

// Send the file
readfile($file);

This will simply fetch the file and forward it's contents to the user. And the header will make the browser save the file as a download.

And you could take this even further. Let's say you save this in a file called script.php in a directory accessible to the user via http://example.com/ftp/ . If you are using apache2 and have mod_rewrite enabled you can create a .htaccess file in this directory containing:

RewriteEngine On
RewriteRule ^(.*)$ script.php?file=$1 [L]

When the user navigates to http://exmaple.com/ftp/README.md your script.php file will be called with $_GET['file'] equal to /README.md and the file from ftp://user:pass@ftp.example.com/README.md will be downloaded on his computer.