function getgoogl($glurl, $apikey) {

	$userurl = rawurlencode($glurl);

	$ch = curl_init('https://www.googleapis.com/urlshortener/v1/url?key='.$apikey); 
	curl_setopt_array($ch, array(
	   CURLOPT_POST => TRUE,
	   CURLOPT_RETURNTRANSFER => TRUE,
	   CURLOPT_HTTPHEADER => array('Content-type: application/json'),
	   CURLOPT_POSTFIELDS => json_encode(array('longUrl' => $userurl))
	   )); 
	$chresults = json_decode(curl_exec($ch));
	curl_close($ch);
	
	return $chresults->id;
	}

http://snipt.org/xglpp

I needed a simple function to shorten a link with goo.gl and wrote this, thought it may help someone. Note: you still need an API key from goo.gl

Shorten with goo.gl

url, google

PHP