I have been working with the http://bit.ly API and decided to change the short URLs on my site to include the short URLs provided by http://bit.ly. The API is pretty straightforward and I created a few WordPress functions to to get it all working.

Before we even start, you would need to registered with http://bit.ly and then check out this page http://bit.ly/a/your_api_key to get your API key and your login.

Now, let’s add a function to automatically create a http://bit.ly short URL when you publish a post. We will hook into the publish_post action and then use the http://bit.ly API to fetch a shortened URL. Place the following into your theme’s function.php file.

add_action('publish_post', 'create_bitly');

function create_bitly($postID) {
	global $wpdb;
	$login = 'YOUR LOGIN'; // change this to your login
	$apikey = 'YOUR API KEY'; // change this to your API key

	$longURL = get_permalink($postID); // here we get the permalink to your post

	// This is the API call to fetch the shortened URL
	$apiurl = 'http://api.bit.ly/v3/shorten?longUrl='.urlencode($longURL).'&login='.$login.'&apiKey='.$apikey;

	// We are using cURL
	$curl = curl_init();
	curl_setopt($curl, CURLOPT_CONNECTTIMEOUT, 5);
	curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
	curl_setopt($curl, CURLOPT_URL, $apiurl);
	$results = json_decode(curl_exec($curl));
	$shortURL =  $results->data->url; // the short URL

	update_post_meta($postID, 'bitlyURL', $shortURL); // adding the short URL to a custom field called bitlyURL

You can read more about the http://bit.ly API here: http://code.google.com/p/bitly-api/wiki/ApiDocumentation

In order to add your new short URL to your header, you first need to remove the default shortlink tag and then create a function that will place the proper code between your <head> tags.

remove_action( 'wp_head', 'wp_shortlink_wp_head', 10, 0 ); // removing the default shortlink
add_action( 'wp_head', 'bilty_shortlink_head'); // adding the new bit.ly shortlink

function bilty_shortlink_head() {
	global $post;
	$shortURL = get_post_meta($post->ID, 'bitlyURL', true);
	if(!empty($shortURL)) {
		echo '<link rel="shortlink" href="'.$shortURL.'" />'."\n";
	} else {
		echo '<link rel="shortlink" href="'.get_bloginfo('url').'?p='.$post->ID.'" />'."\n";

If you want to display your new short URLs, you can do so by using the `wp_get_shortlink()` function. But first you need to make sure that WordPress knows to replace the default short URL with the new http://bit.ly short URL.

add_filter('pre_get_shortlink', 'get_bitly_shortlink'); // filtering the WP function

function get_bitly_shortlink() {
	global $post;
	$shortURL = get_post_meta($post->ID, 'bitlyURL', true);
	if(!empty($shortURL)) {
		 return $shortURL;
	} else {
		return get_bloginfo('url').'?p='.$post->ID;

You can place the following code anywhere within the loop of your single.php theme file to display your short URL.

Short URL: <a href="<?php echo wp_get_shortlink($post->ID); ?>" title="<?php the_title(); ?>"><?php echo wp_get_shortlink($post->ID); ?></a>