add_action function not working when publishing post or page

Why this code, not working in my wordpress?

/*-----------------------------------------------------------------------------------*/
# SHORT URL
/*-----------------------------------------------------------------------------------*/

/* If the link has already been created, get it from the post meta instead of making a curl request for every page load. */
function link_pendek() {
    global $post;
    $_link = get_permalink($post->ID);
    $_existing = get_post_meta($post->ID, 'short_url', true);
    if ($_existing !== false && !empty($_existing)) return;
    $_link = curl_get_result('http://api.bit.ly/v3/shorten?login=USERNAME&apiKey=APIKEY&longUrl='.urlencode($_link).'&format=txt');
    update_post_meta($post->ID, 'short_url', $_link);
}

/* returns a result from url */
function curl_get_result($url) {
    $ch = curl_init();
    $timeout = 5;
    curl_setopt($ch,CURLOPT_URL,$url);
    curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
    curl_setopt($ch,CURLOPT_CONNECTTIMEOUT,$timeout);
    $data = curl_exec($ch);
    curl_close($ch);
    return $data;
}
add_action('publish_page', 'link_pendek');
add_action('publish_post', 'link_pendek');