Symfony2 - Force file download

Question

I'm trying to download a file when a user clicks on download link.

In Controller:

    $response = new Response();
    $response->headers->set('Content-type', 'application/octect-stream');
    $response->headers->set('Content-Disposition', sprintf('attachment; filename="%s"', $filename));
    $response->headers->set('Content-Length', filesize($filename));

    return $response;

This is opening the dialog box to save the file, but it says the file is 0 bytes. And changing it to:

        $response = new Response();
        $response->headers->set('Content-type', 'application/octect-stream');
        $response->headers->set('Content-Disposition', sprintf('attachment; filename="%s"', $filename));
        $response->headers->set('Content-Length', filesize($filename));
        $response->headers->set('Content-Transfer-Encoding', 'binary');
        $response->setContent(readfile($filename));

        return $response;

I get a bunch of weird characters instead of the file download dialog box.

Finally, switching the "setContent" line to:

    $response->setContent(file_get_contents($filename));

It returns a PHP error:

Fatal error: Allowed memory size...

Any clues on how to achieve this? I've done it before in PHP (wihtout MVC), but I don't know what can be missing to do it through Symfony2...

Maybe the solution is setting the memory_limit in PHP.INI, but I guess it´s not the best practice...

Answer 1

The most comfortable solution is

use Symfony\Component\HttpFoundation\BinaryFileResponse;
use Symfony\Component\HttpFoundation\ResponseHeaderBag;

$response = new BinaryFileResponse($file);
$response->setContentDisposition(ResponseHeaderBag::DISPOSITION_ATTACHMENT);

return $response;

Answer 2

I finally solved this without X-SendFile (which is probably the best practice). Anyway, for those who can't get X-Sendfile apache module to work (shared hosting), here's a solution:

// Generate response
$response = new Response();

// Set headers
$response->headers->set('Cache-Control', 'private');
$response->headers->set('Content-type', mime_content_type($filename));
$response->headers->set('Content-Disposition', 'attachment; filename="' . basename($filename) . '";');
$response->headers->set('Content-length', filesize($filename));

// Send headers before outputting anything
$response->sendHeaders();

$response->setContent(file_get_contents($filename));

return $response;

Answer 3

You shouldn't use PHP for downloading files because it's a task for an Apache or Nginx server. Best option is to use X-Accel-Redirect (in case of Nginx) / X-Sendfile (in case of Apache) headers for file downloading.

Following action snippet can be used with configured Nginx to download files from Symfony2:

return new Response('', 200, array('X-Accel-Redirect' => $filename));

UPD1: Code for apache with configured mod_xsendfile:

return new Response('', 200, array(
    'X-Sendfile'          => $filename,
    'Content-type'        => 'application/octet-stream',
    'Content-Disposition' => sprintf('attachment; filename="%s"', $filename))
);

Answer 4

As of Symfony 3.2 you can use the file() controller helper which is a shortcut for creating a BinaryFileResponse as mentioned in a previous answer:

public function fileAction()
{
    // send the file contents and force the browser to download it
    return $this->file('/path/to/some_file.pdf');
}