#!/usr/bin/php

<?php

$client_id      =   'yourClientId' ;

$params = array(
    'response_type' => 'code',
    'client_id'     => $client_id, 
    'redirect_uri'  => 'urn:ietf:wg:oauth:2.0:oob',
    'scope'         => 'https://www.googleapis.com/auth/youtube.upload',
) ;
$url = 'https://accounts.google.com/o/oauth2/auth?' . http_build_query($params) ;
echo $url . "\n" ;

?>