Note: this is not a plug and play WordPress plugin which you can just download and activate.

This is more like a starting point for filtering and searching any post types in WordPress. As a starting point check

• src/markup folder for markup.
• src/js folder for JS.
• src/css folder for CSS.

In most cases you probably want to handle markup in your theme or block. Same for JS and CSS although you can import assets directly from the plugin.

In other words, this plugin doesn't do anything on front end by default. That's up to your project.

WP_Query Route To REST API is the engine of MEOM filters.

It adds new route /wp-json/wp_query/args/ to REST API. And in JS we can query content with similar logic than in WP_Query.

Recommended method installing WP_Query Route To REST API plugin is using composer.

• @wordpress/a11y.
• @wordpress/url.

Recommended method is install those NPM modules in your project.

General logic of MEOM filters is returning HTML from the REST queries. Which means we can use same template files as in PHP.

This saves a little bit of time when same markup can be used in PHP and in JS filtering logic.

First, check inc/filters.php file.

From default_data you might want to change empty message.

Locate code:

// Build logic for this where you pull your HTML markup.
// Can be any post type and any template file.
if ( 'post' === $args['post_type'] ) {
    get_template_part( 'partials/post/post-item' );
}

In here change any template file from your theme or add any new post types your are filtering in your project.

For example:

if ( 'product' === $args['post_type'] ) {
    get_template_part( 'partials/post/product-item' );
} else {
    get_template_part( 'partials/post/default-item' );
}

Filters are configured using filters-config.json file. This helps parity between HTML markup and JS.

Add new post type keys, and inside post types new tax_query items. Demo is missing meta_query automated logic at the moment.

In filters-config.json there is post and page post type examples.

Also search and order examples are provided.

• src/markup/filters.php file for markup.
• src/js/meom-filters.js file for JS.

In markup there are data attributes data-meom-filters which we use in JS.

• data-meom-filters="form" for filters form.
• data-meom-filters-post-type="post" for which post type form is used.
• data-meom-filters="items-content" where the query results are generated.

Feel free to change this logic using classes if needed.

Aucor WP_Query enables similar logic for REST JS queries. Therefore object called args looks similar than in PHP.

// Default filter arguments.
const args = {
    post_type: postType,
    posts_per_page: 4,
    paged: 1,
};

After that look for if (postType === 'post') {} check what happens for other arguments.

In the end these arguments are passed into endpoint using fetch JS API. And it returns HTML markup from wanted template file. Remember inc/filters.php file mentioned before.

In the same time we add query arguments, we also update object urlObject. And update URL query parameters based on this.

This means that you can share the URL or refresh the page, and the query still works.

Check initFilters function where we update checkboxes or other fields based on URL.

FacetWP can be better plug and play solution.