Related Posts with SearchWP

/**
 * Related Posts
 *
 */
function ea_related_posts() {

	$related_to_show = 6;
	$related = ea_get_related_posts( $related_to_show );

	// Display Related Posts
	$loop = new WP_Query( array(
		'post__in' => $related,
		'orderby'  => 'post__in',
		'posts_per_page' => $related_to_show,
	) );

	if( $loop->have_posts() ):
		echo '<section class="related-posts">';
		echo '<header><h3>Related Posts</h3></header>';
		while( $loop->have_posts() ): $loop->the_post();
			get_template_part( 'partials/archive', 'related' );
		endwhile;
		echo '</section>';
	endif;
	wp_reset_postdata();
}
add_action( 'genesis_after_entry', 'ea_related_posts' );

/**
 * Get Related Posts
 *
 */
function ea_get_related_posts( $related_to_show = false ) {

	$related_to_show = !empty( $related_to_show ) ? intval( $related_to_show ) : get_option( 'posts_per_page' );

	// Use SearchWP
	if( class_exists( 'SearchWP_Related' ) ) {

		// Instantiate SearchWP Related
		$searchwp_related = new SearchWP_Related();

		// Use the keywords as defined in the SearchWP Related meta box
		$keywords = get_post_meta( get_the_ID(), $searchwp_related->meta_key, true );
		if( empty( $keywords ) )
			$keywords = get_the_title();

		$args = array(
			's'              => $keywords,  // The stored keywords to use
			'engine'         => 'default',  // the SearchWP engine to use
			'posts_per_page' => $related_to_show,
			'post__not_in'   => array( get_the_ID() ),
		);

		// Retrieve Related content for the current post
		$related = $searchwp_related->get( $args );

	// Fallback, use primary category
	} else {
		$loop = new WP_Query( array(
			'posts_per_page' => $related_to_show,
			'category_name' => ea_first_term( 'category', 'slug' ),
			'post__not_in' => array( get_the_ID() ),
			'fields' => 'ids',
		));
    	if( ! is_wp_error( $loop ) && !empty( $loop->posts ) )
			$related = $loop->posts;
	}

	return $related;
}