Searching by specific post-types

There are two different methods for stripping post-types from search results. Specific post-types can be removed from your entire search index, or you can filter the results based on the post-type.

Removing a post-type from the Algolia search index.

The strattic_search_item filter can be used to remove items from the search results. The following snippet will limit search results to the “post” post type. Note that strattic_search_item is called on each item going into Algolia.

Note: You must reindex Algolia by visiting /?strattic_search_index_update=force to ensure this change appears in your search results.

<?php

/**
 * Enable only one specific post-type in Strattic search.
 */
add_filter(
	'strattic_search_item',
	function( $data, $post ) {
		if ( 'post' !== $post->post_type ) {
			$data = null;
		}
		return $data;
	},
	1,
	2
);

Filter search results based on post-type

For some situations, you may not want to totally remove a post-type from your entire search index. In this situation, you need to specifically filter out those results. To do this, you need to send the post-type for each post to Algolia (set via the strattic_search_formatting filter), set an Algolia facet (used for only returning results based on a specification you set) and to change the request sent to Algolia (achieved via editing the JavaScript variable strattic_algolia.filters).

Here is some example code which allows you to only return results for the “post” post-type. You can adjust the JavaScript variable strattic_algolia.filters via any method you wish. A popular option for this is via filter tabs on your search page (which you would need to implement manually).

Note: You must reindex Algolia by visiting /?strattic_search_index_update=force to ensure this change appears in your search results.

<?php

/**
 * Adds post-type specific search for Algolia.
 */
class Strattic_Search_Post_Types {

	/**
	 * Constructor.
	 */
	public function __construct() {
		add_action( 'wp_head', array( $this, 'inline_script' ) );
		add_action( 'strattic_search_formatting', array( $this, 'send_post_type_to_algolia' ) );
		add_action( 'strattic_facets', array( $this, 'algolia_facets' ) );
	}

	/**
	 * Inline script to set the Algolia filter.
	 *
	 * Can also set this in an external script or in the footer.
	 */
	public function inline_script() {
		echo "
		<script>
		let strattic_algolia     = [];
		strattic_algolia.filters = \"'post_type': 'post'\";
		</script>
		";
	}

	/*
	 * Add post-type for each post sent to Algolia.
	 *
	 * @param array $item The search item.
	 * @return array The modified search item.
	 */
	public function send_post_type_to_algolia( $item ) {
		$post_id           = $item['id'];
		$item['post_type'] = get_post_type( $post_id );

		return $item;
	}

	/**
	 * Add post-type attribute for faceting in Algolia.
	 *
	 * @param array $attributes_for_faceting Attributes for faceting.
	 * @return array
	 */
	public function algolia_facets( $attributes_for_faceting ) {
		$attributes_for_faceting[] = 'searchable(post_type)';

		return $attributes_for_faceting;		
	}

}
new Strattic_Search_Post_Types;