index.php

<?php

namespace WPPerformance\Search;

require_once __DIR__ . '/vendor/autoload.php';
require_once __DIR__ . '/src/SearchClient.php';
require_once __DIR__ . '/src/wp-cli.php';

use WPPerformance\Search\Inc\Search_Client;

/**
 * Plugin Name:     WP Performance Search Meilisearch
 * Description:     Add Meilisearch Search feature
 * Text Domain:     wp-performance-meilisearch
 * Version:         1.0.0
 */
if (!defined('WP_ENV')) {
    define('WP_ENV', 'development');
}
/**
 * get current post types
 */
function getPostTypes()
{
    return ['post', 'page', 'snippet'];
}

/**
 * get meta keys autorized for meilisearch
 */
function getMetaKeys()
{
    // exemple for seo press
    return ['_seopress_titles_title', '_seopress_titles_desc'];
}

/**
 * get index name for meilisearch
 * add prefix env
 */
function wp_perf_search_index_name($defaultName = 'content')
{
    return WP_ENV . '_' . $defaultName;
}

add_action(
    'wp_footer',
    function () {
        echo '<script type="text/javascript">'
            . 'var MEILISEARCH_URL = "' . MEILISEARCH_URL . '";'
            . 'var MEILISEARCH_KEY_PUBLIC = "' . MEILISEARCH_KEY_PUBLIC . '";'
            . 'var MEILISEARCH_APP_INDEX = "' . namespace\wp_perf_search_index_name() . '";'
            . '</script>';
    }
);

// init keys for search
Search_Client::initKeys(MEILISEARCH_URL, MEILISEARCH_KEY_SECRET);

/**
 * map data
 */
function wp_perf_post_to_record($post)
{
    /** add tags */
    $tags = array_map(function (\WP_Term $term) {
        return $term->name;
    }, wp_get_post_terms($post->ID, 'post_tag'));

    /** add cat */
    $cat = array_map(function (\WP_Term $term) {
        return $term->name;
    }, wp_get_post_terms($post->ID, 'category'));

    return [
        'id' => $post->ID,
        'title' => $post->post_title,
        'author' => [
            'id' => $post->post_author,
            'name' => get_user_by('ID', $post->post_author)->display_name,
        ],
        'excerpt' => html_entity_decode(get_the_excerpt($post)),
        'content' => html_entity_decode(strip_tags($post->post_content)),
        'tags' => $tags,
        'categories' => $cat,
        'url' => get_permalink($post->ID),
        'custom_field' => get_post_meta($post->id, $post->custom_type),
    ];
}

/** same for all but you can change by post type */
// add_filter('post_to_record', __NAMESPACE__ . '\wp_perf_post_to_record');
// add_filter('snippet_to_record', __NAMESPACE__ . '\wp_perf_post_to_record');
// add_filter('page_to_record', __NAMESPACE__ . '\wp_perf_post_to_record');

/**
 * hook meta update
 */
function wp_perf_update_post_meta($meta_id, $object_id, $meta_key, $_meta_value)
{
    $search = Search_Client::getInstance();

    if (in_array($meta_key, namespace\getMetaKeys())) {
        $index = $search->index(
            namespace\wp_perf_search_index_name()
        );

        $index->updateDocuments([
            'id' => $object_id,
            $meta_key => $_meta_value,
        ]);
    }
}

add_action('update_post_meta', __NAMESPACE__ . '\wp_perf_update_post_meta', 10, 4);

/**
 * hook post update or create
 */
function wp_perf_update_post($id, \WP_Post $post, $update)
{
    if (wp_is_post_revision($id) || wp_is_post_autosave($id)) {
        return $post;
    }

    if (!in_array($post->post_type, namespace\getPostTypes())) {
        return $post;
    }

    $search = Search_Client::getInstance();

    $record = (array) wp_perf_post_to_record($post);

    if (!isset($record['id'])) {
        $record['id'] = $post->ID;
    }

    $index = $search->index(
        namespace\wp_perf_search_index_name()
    );

    if ('trash' == $post->post_status) {
        $index->deleteDocument($record['id']);
    } else {
        $index->updateDocuments([$record]);
    }

    return $post;
}

add_action('save_post', __NAMESPACE__ . '\wp_perf_update_post', 10, 3);