why csv export not working? - symfony

Question

I try to do a csv export on my symfony project and i think that something is wrong because the function return a simple response and don't download the csv.
here is the function:
public function exportCsv($customers)
{
$fileName = "export_" . date("d_m_Y") . ".csv";
$response = new StreamedResponse();
$handle = fopen('php://output', 'w+');
fputcsv($handle, array('Name',
'Adress',
'City',
'Code'
), ';');
foreach ($customers as $index => $custom)
{
fputcsv($handle,array(
$custom->getName(),
$custom->getAdress(),
$custom->getCity(),
$client->getCode(),
),';');
}
fclose($handle);
$response->setStatusCode(200);
$response->headers->set('Content-Type', 'text/csv; charset=utf-8');
$response->headers->set('Content-Disposition','attachment; filename='.$fileName);
return $response;
}

Answer 1

After creating a streamed response object, you needed to add the callback function that will fill out your response object with content: $response->setCallback().
public function exportCsv($customers)
{
$fileName = "export_" . date("d_m_Y") . ".csv";
$response = new StreamedResponse();
$response->setCallback(function() {
$handle = fopen('php://output', 'w+');
fputcsv($handle, array('Name', 'Adress', 'City', 'Code'),';');
foreach ($customers as $index => $custom)
{
fputcsv($handle,array(
$custom->getName(),
$custom->getAdress(),
$custom->getCity(),
$client->getCode(),
),';');
}
fclose($handle);
});
$response->setStatusCode(200);
$response->headers->set('Content-Type', 'text/csv; charset=utf-8');
$response->headers->set('Content-Disposition','attachment;
filename='.$fileName);
return $response;
}