Best way to send HTTP response code in PHP - php

Question

From reading the php spec and other questions on Stack Overflow, I can see three ways of sending an HTTP response code from PHP:
header("HTTP/1.0 404 Not Found");
^ ^ ^
A B C
header(" ", false, 404);
^ ^ ^
C D B
http_response_code(404);
^
B
A: Defines HTTP header
B: Response code
C: Message
D: To replace previous header or not
What is the difference between these and which one is the best to use? Is my understanding of the parameters correct?
Thanks,
Tugzrida.

Answer 1

To answer your question about what is the difference, I found this comment in the PHP docs (thanks Steven):
http_response_code is basically a shorthand way of writing a http
status header, with the added bonus that PHP will work out a suitable
Reason Phrase to provide by matching your response code to one of the
values in an enumeration it maintains within
php-src/main/http_status_codes.h. Note that this means your response
code must match a response code that PHP knows about. You can't create
your own response codes using this method, however you can using the
header method.
In summary - The differences between http_response_code and header
for setting response codes:
Using http_response_code will cause PHP to match and apply a Reason Phrase from a list of Reason Phrases that are hard-coded into
the PHP source code.
Because of point 1 above, if you use http_response_code you must set a code that PHP knows about. You can't set your own custom code,
however you can set a custom code (and Reason Phrase) if you use the
header method.
I was curious about how some popular frameworks send the header in a standard response:
Symfony (and Laravel, by inheritance) sets the raw header:
// status
header(sprintf('HTTP/%s %s %s', $this->version, $this->statusCode, $this->statusText), true, $this->statusCode);
Zend Framework 2 also sets the raw header:
public function renderStatusLine()
{
$status = sprintf(
'HTTP/%s %d %s',
$this->getVersion(),
$this->getStatusCode(),
$this->getReasonPhrase()
);
return trim($status);
}
And so does Yii
protected function sendHeaders()
{
if (headers_sent()) {
return;
}
$statusCode = $this->getStatusCode();
header("HTTP/{$this->version} $statusCode {$this->statusText}");
// ...