When we converted the Pop Art Blog to use WordPress, I learned some clever tricks that I would like to share with you. If you like what we’ve done around here, you might be interested in some of these techniques for your own site.

Use RSS Excerpts to Strip All HTML

/*
	just like the_excerpt, but really strips all the HTML, including BR tags
*/
<p><?php the_excerpt_rss(); ?></p>

We wanted to display a post excerpt on most pages. Normally, I would just use wordpress’ the_excerpt function. It automatically displays the post excerpt if it exists, and if not, then it grabs the first 50 words of the post, and even strips the HTML! Sounds great, right? Except for one thing — it doesn’t strip line breaks, so instead of a page full of single-paragraph excerpts, I had several posts with two small paragraphs displaying. Not a big deal, but it was messing up our design.

After doing a little digging in the wordpress documentation, I found that the_excerpt_rss does exactly what I was looking for. It’s intended to be used in RSS templates, but you can use it in your regular pages and it works just as well. The only hiccup is that you’ll need to wrap it in a <p> yourself.

Use the Nickname Field for Job Titles

<?php the_author_meta('nickname'); ?>

Our design shows the job title under everyone’s name. There’s no “job title” field in the user accounts, but I was able to repurpose the nickname field. To display it in the site, just use the code shown above in your post templates. Remember, the people looking at your site won’t know that you’re using the “wrong” database field! (You know, unless you tell them, like I’m doing.)

Bit.ly Shortener for Twitter Links

/*
	Bit.ly URL Shortener
	Automatically shorten a URL using the Bit.ly API
	based on code from http://davidwalsh.name/bitly-php
*/
function make_bitly_url($url) {
	$login = 'YOUR BIT.LY LOGIN';
	$appkey = 'YOUR BIT.LY API KEY';
	$format = 'xml';
	$version = '2.0.1';
	$bitly = 'http://api.bit.ly/shorten?version='.$version.'&longUrl='.urlencode($url).'&login='.$login.'&apiKey='.$appkey.'&format='.$format;
	$response = file_get_contents($bitly);
	//parse depending on desired format
	if(strtolower($format) == 'json') {
		$json = @json_decode($response,true);
		return $json['results'][$url]['shortUrl'];
	} else { //xml
		$xml = simplexml_load_string($response);
		return 'http://bit.ly/'.$xml->results->nodeKeyVal->hash;
	}
}

Adding a “retweet this” link at the bottom of every post is pretty easy. You just link to twitter.com and pass a “status” query string in the URL with whatever you want their tweet to include — namely, the URL to the post they’re retweeting. But our URLs can get pretty lengthy, since they include the post title. Obviously, with Twitter’s 140-character limit, every character counts. To get around this, I found some code by David Walsh to make a bit.ly short URL. It works great, but you’ll need to register for an API key on their site to use it. This code goes in your functions.php file, and then you can call it from any post loop like this:

<?php echo make_bitly_url(get_permalink()); ?>

Use a Custom Default Gravatar

/*
	Add new default avatars
	based on code from http://wpengineer.com/add-avatar-to-wordpress-default/
*/
if ( !function_exists('fb_addgravatar') ) {
	function fb_addgravatar( $avatar_defaults ) {
		$stormtrooper = get_bloginfo('template_directory').'/images/avatar.png';
		$avatar_defaults[$stormtrooper] = 'Storm Trooper';
		return $avatar_defaults;
	}
	add_filter( 'avatar_defaults', 'fb_addgravatar' );
}

WordPress’ built-in support for gravatars in comments is fantastic, but if your commenters don’t have a gravatar account, the default avatar will be displayed. WordPress lets you choose between a simple gray silhouette or several dynamically generated icons, none of which really fit our design. Luckily, I found this code that lets you add your own default avatar to the list — in our case, a lovely photo of a storm trooper. This code goes in your functions.php file, and it adds a new option to the default gravatar list in your admin area.

Use HTML in User Profiles

/*
	Turn off HTML filter for user profiles
*/
remove_filter('pre_user_description', 'wp_filter_kses');

Our fancy profile pages use the “Biographical Info” field in the user profiles. The only problem is that by default, wordpress strips any HTML from it. You can disable that feature by adding this bit of code to your functions.php file.

Add More RSS Feeds

<link rel="alternate" type="application/atom+xml" title="<?php bloginfo('name'); ?> Full Posts" href="<?php bloginfo('atom_url'); ?>" />
<?php
	// add comments feed on single-post pages
	if (is_single()) {
		while (have_posts()) : the_post();
			if ('open' == $post->comment_status) : /* If comments are open */
?>
<link rel="alternate" type="application/atom+xml" title="Comments on <?php the_title(); ?>" href="<?php bloginfo('url'); ?>/index.php?feed=atom&amp;p=<?php the_ID(); ?>" />
<?php
			endif;
		endwhile;
		rewind_posts();
	// add category feed on category archives
	} else if (is_category()) {
		$category = get_the_category();
?>
<link rel="alternate" type="application/atom+xml" title="Posts in the <?php echo $category[0]->cat_name; ?> category" href="<?php echo get_category_feed_link( $category[0]->cat_ID, 'atom' ); ?>" />
<?php
	// add tag feed on tag archives
	} else if (is_tag()) {
?>
<link rel="alternate" type="application/atom+xml" title="Posts tagged with <?php single_tag_title(); ?>" href="<?php echo get_tag_feed_link( get_query_var('tag_id'), 'atom' ); ?>" />
<?php
	// add author feed on author pages
	} else if (is_author()) {
		if(isset($_GET['author_name'])) :
		$curauth = get_userdatabylogin($author_name);
		else :
		$curauth = get_userdata(intval($author));
		endif;
		$authorfeedlink = get_author_feed_link( $curauth->ID, 'atom' );
	?>
<link rel="alternate" type="application/atom+xml" title="Posts by <?php echo $curauth->display_name; ?>" href="<?php echo $authorfeedlink; ?>" />
<?php
	}
?>

Finally, one of the best (and relatively unknown) features of wordpress is that you can get an RSS feed for just about every page on the site, just by adding /feed/ to the end of the URL. I wanted to take advantage of this feature to add link elements for those special feeds on different pages — for example, a feed for an author’s posts on their profile page, or for comments on a post on that post’s page. The above code is a little convoluted, but it includes all the logic to add the following feeds on the appropriate pages:

• Complete blog feed on every page
• Comments feed on individual post pages
• Category feeds on category pages
• Tag feeds on tag pages
• Author feeds on author profile pages

Note that I’ve set this up to provide Atom feeds, but you can change it by replacing every instance of atom with rss2. This code goes in your header.php file, near the rest of your meta and link elements.