<?php
$USERAGENT   = "Please change this!";
$REQUEST_URL = "https://api.spiget.org/v2/resources/12345";

$options     = array('http' => array('user_agent' => $USERAGENT));
$context     = stream_context_create($options);
$response    = @file_get_contents($REQUEST_URL, false, $context);

if(!isset($response) || is_null($response)) {
  // error handling
}

$data = json_decode($response, true);
// TODO: process data
print_r($data);