It’s possible to integrate all kinds of external data to Relevanssi weights. Koko Analytics is a great analytics plugin. It collects stats about your visitors and stores them in the local database, which means those stats are available for Relevanssi.
For some sites, this makes a lot of sense. For example, I have Kirjavinkit, a book review site with an archive of about 10,000 book review posts. The popularity of the posts is primarily driven by external search traffic and seems like a good indicator of what users find interesting and valuable.
Integrating the Koko stats as a factor in the weight calculations is straightforward. The best tool to use is the relevanssi_results filter hook. It lets us modify the weights of the posts. For each post, we calculate a weight multiplier based on the visitor stats and then multiple the weight of the post with that.
I add some normalization here. I normalize all weights to the 1–1,000 range. I also set the minimum weight to 1 to avoid punishing the rarely-visited posts.
To avoid performance problems, I fetch all the stats once and store them in a global variable so that when the function processes all posts, it only needs to make one database request.
Here’s the code:
function rlv_koko_weight( int $post_id ) : float {
global $relevanssi_koko_weights;
if ( empty( $relevanssi_koko_weights ) ) {
global $wpdb;
$stats = $wpdb->get_results( "SELECT id, SUM(visitors) AS visits FROM {$wpdb->prefix}koko_analytics_post_stats GROUP BY id" );
foreach ( $stats as $post_stats ) {
$relevanssi_koko_weights[ $post_stats->id ] = $post_stats->visits;
}
$max_visits = max( $relevanssi_koko_weights );
$factor = $max_visits / 1000; // This controls the normalization.
foreach ( $relevanssi_koko_weights as $post_id => $visits ) {
$weight = $visits / $factor;
if ( $weight < 1 ) {
$weight = 1;
}
$relevanssi_koko_weights[ $post_id ] = $weight;
}
}
return $relevanssi_koko_weights[ $post_id ] ?? 1;
}
add_filter( 'relevanssi_results', 'rlv_koko_weights' );
function rlv_koko_weights( $post_weights ) {
foreach ( $post_weights as $post_id => $weight ) {
$post_weights[ $post_id ] = rlv_koko_weight( intval( $post_id ) ) * $weight;
}
return $post_weights;
}