I do not think that you need to use http_build_query and perhaps your URL should be 'http://localhost:8080/snacks'

This code works for me in moodle. In $postdata I simply pass an array of parameters.

public static function curl_fetch($url,$postdata=false)
{
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_HEADER, false);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    if ($postdata) {
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata);
    }
    $contents = curl_exec($ch);
    curl_close($ch);
    return $contents;
}

Hi Daryoush,

have you tried the moodle core class "curl"?

Here an example:

require_once('config.php');
require_once($CFG->libdir.'/filelib.php');
$curl = new curl();

$url = 'http://localhost:8080/snacks';
$params = array('asid'=> 2, 'userid' => 3, 'sbm_fpth' => 5);
$result = $curl->get($url, $params);
print_object($result);

Best regards
Andreas

I was given advice to use only internal CURL class when developing with Moodle because - "Many moodle sites sit behind a web proxy and moodle uses an internal curl() class to manage this" by Dan Mardsen.
So it's probably way to go. You can find it in lib/filelib.php around line 2704.

I remember when I just started to work with internal CURL I had a problem to reach  APIs in development (maybe because of non : 80 port or because of SSL), so ngrok  ( https://ngrok.com/ ) might be handy.