Metronet

Today I was assigned an exciting task for a few of our sites on WordPress.

Make «Mest populære» based on number of FB likes.

I thought this would make a great blog post since it would utilize some really neat WordPress functionality.

To make this easier let’s break this up into 2 parts.

Part 1 – Functions.php

Here’s what you’ll need to add to your theme’s functions.php or a plugin of some sort.

[php]

// Sort Posts by Facebook Likes
function mn_fb_like_sort_hourly() {

global $wpdb;

// Loop Through All Posts
$args = array( ‘posts_per_page’ => ‘-1′ );
$the_query = new WP_Query( $args );
while ( $the_query->have_posts() ) : $the_query->the_post();

// Get Facebook Likes From FB Graph API
$data = file_get_contents(‘http://graph.facebook.com/?id=’. get_permalink());
$obj = json_decode($data);
$like_no = intval($obj->{‘shares’});

// Add Facebook Likes to Post Meta
update_post_meta(get_the_ID(), ‘_mn_fb_likes’, $like_no);

endwhile;
wp_reset_postdata();
}
add_action(‘mn_fb_like_sort’, ‘mn_fb_like_sort_hourly’);

function mn_fb_like_sort_cron() {
if ( !wp_next_scheduled( ‘mn_fb_like_sort’ ) ) {
wp_schedule_event(time(), ‘hourly’, ‘mn_fb_like_sort’);
}
}
add_action(‘wp’, ‘mn_fb_like_sort_cron’);

[/php]

Let’s loop through all of our posts.

[php]

// Loop Through All Posts
$args = array( ‘posts_per_page’ => ‘-1′ );
$the_query = new WP_Query( $args );
while ( $the_query->have_posts() ) : $the_query->the_post();

[/php]

Now let’s use Facebook’s Graph API to get the number of likes.

[php]

// Get Facebook Likes From FB Graph API
$data = file_get_contents(‘http://graph.facebook.com/?id=’. get_permalink());
$obj = json_decode($data);
$like_no = intval($obj->{‘shares’});

[/php]

Let’s add the number of likes to post meta. We’ll need this to sort later.

[php]

// Add Facebook Likes to Post Meta
update_post_meta(get_the_ID(), ‘_mn_fb_likes’, $like_no);

[/php]

Lastly, let’s use wp_schedule_event() to update these hourly. We don’t need to update these on every page load, causing a decrease in site performance.

[php]

function mn_fb_like_sort_cron() {
if ( !wp_next_scheduled( ‘mn_fb_like_sort’ ) ) {
wp_schedule_event(time(), ‘hourly’, ‘mn_fb_like_sort’);
}
}
add_action(‘wp’, ‘mn_fb_like_sort_cron’);

[/php]

That’s it for functions.php. Let’s move on to displaying these in our template/theme somewhere.

Part 2 – Theme/Template

Here’s an example loop. Let’s get the 4 most liked posts.

[php]

// Loop Through All Posts
$args = array(
‘posts_per_page’     => ’4′,
‘meta_key’             => ‘_mn_fb_likes’,
‘orderby’            => ‘meta_value_num’,
‘order’                => ‘DESC’
);
$query = new WP_Query( $args );

while ( $query->have_posts() ) : $query->the_post();
// Loop!
endwhile;
wp_reset_postdata();

[/php]

Let me know what you think or if you’ve accomplished this another way. Comments and/or criticism are always welcome!

Also, if your looking to get more involved with WordPress in and around the Oslo area check out the Oslo WordPress Meetup Group.