PHP cURL HTTP CODE return 0 – How to solve?

Description

I was trying to use cURL in PHP, but somehow HTTP code returns 0 instead of any valid response code such as 200, 500, or 403.

This is the code I am using

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $this->api . '/login');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'Referer: ' . $this->api
]);
$httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
$r = curl_exec($ch);

curl_close($ch);
        
if ($httpcode != 200) {
    throw new Exception('API returned HTTP code of ' . $httpcode);
}

Some of you might noticed, the error lies in line 11 – $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);

That line should be called after executing the cURL.

Solution

The solution is quite obvious. I need to call curl_getinfo after curl_exec

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $this->api . '/login');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'Referer: ' . $this->api
]);
$r = curl_exec($ch);
$httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);

curl_close($ch);
        
if ($httpcode != 200) {
    throw new Exception('API returned HTTP code of ' . $httpcode);
}

Problem solved!