/**
* Serialize HTTP headers to be sent in an FCGI record.
*
* @param HttpResponse $response
* @param int $size
* @return string
*/
protected function serializeHeaders(HttpResponse $response, int $size = null) : string
{
$reason = \trim($response->getReasonPhrase());
if ('' === $reason) {
$reason = Http::getReason($response->getStatusCode());
}
$buffer = \sprintf("Status: %03u%s\r\n", $response->getStatusCode(), \rtrim(' ' . $reason));
if ($size !== null) {
$buffer .= "Content-Length: {$size}\r\n";
}
foreach ($response->getHeaders() as $name => $header) {
$name = Http::normalizeHeaderName($name);
foreach ($header as $value) {
$buffer .= $name . ': ' . $value . "\r\n";
}
}
return $buffer;
}