PHP - CURL strange behaviour while setting headers - php

Question

I have written a function in PHP to send a CURl request.
The code is given below.
function curl_post($url,$fields,$headers=[],$connect_timeout = 3,$timeout = 20) {
$ch = curl_init();
$postvars = '';
foreach($fields as $key=>$value) {
$postvars .= $key . "=" . $value . "&";
}
$postvars = trim($postvars,'&');
$postvars = json_encode($fields);
curl_setopt($ch,CURLOPT_URL,$url);
curl_setopt($ch,CURLOPT_POST, 1); //0 for a get request
curl_setopt($ch,CURLOPT_POSTFIELDS,$postvars);
curl_setopt($ch,CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch,CURLOPT_CONNECTTIMEOUT ,$connect_timeout);
curl_setopt($ch,$timeout, 20);
$refined_headers = [];
if(sizeof($headers)) {
foreach($headers as $name => $value) {
$refined_headers[] = "'".$name.": ".$value."'";
}
print_r($refined_headers);
//$refined_headers = ['Content-Type: application/json'];
//echo $refined_headers;exit;
curl_setopt($ch,CURLOPT_HTTPHEADER,$refined_headers);
}
$response = curl_exec($ch);
$info = curl_getinfo($ch,CURLINFO_CONTENT_TYPE);
print_r($info);
curl_close ($ch);
return $response;
}
So I called the function like this
$url = API_ENDPOINT.$method.'/';
$response = curl_post($url,$params_to_send,$headers);
echo $response;
where $url contains my API url and $params contain the parameters as associative array and $headers as follows
$headers = ['Content-Type'=>'application/json'];
My problem is that, the content type header is setting. But when I manually set it inside the curl_post function like
$refined_headers = ['Content-Type: application/json']
it is working perfectly.
What is the problem with my code.

Answer 1

Fixed the issue. The problem was
I put two single quotes before and after the header, which was not needed
$refined_headers[] = "'".$name.": ".$value."'";
I changed that to the following and the issueis resolved.
$refined_headers[] = $name.": ".$value;