Bang Faceted Search

A faceted search is one that allows you to drill down by various fields: price, size, colour, shipping location etc. It complements a free text search rather than replaces it.

Using this plugin, you can create a faceted search interface for your pages, posts, or any other custom post type. You can add “facets” for:

• Taxonomies
• Custom fields
• Dates (day, week, month or year)
• Author

These facets are widgets that can be easily changed in the admin interface.

You can have multiple search pages for different post types. If your WordPress installation uses multi-site, you can search across the different sites.

1. Upload the bang-faceted-search directory to your /wp-content/plugins/ directory
2. Activate the plugin through the ‘Plugins’ menu in WordPress
3. Create a template search.php in your theme
4. Go to Settings > Faceted Search to set up your search pages.

Creating a search page

By default, you’ll have a single search address, at the site root /. This lines up with WordPress search.

In the WordPress admin adrea, go to Settings > Faceted Search. At the top is

Creating a search template

You need to create a search template in your theme called search.php, if you don’t already have one. This template will be used whenever the user searches your site. You can have more than one search template, each.

Add this code to your functions.php to create a search-specific sidebar:

register_sidebar(array(
  'name' => 'Search',
  'id' => 'search'
));

Your search template should include that sidebar:

<?php dynamic_sidebar('search'); ?>

Then in the admin interface, drag Facet widgets into that sidebar to add, customise and re-order the search widgets for your site.

Customising the faceted search

Your site can have more than the default search page, and you can use the faceted search plugin to search custom post types.

To make a custom search, create a page with a custom template in your theme. For example, if you have a page called /products, then create a template in your theme called products.php. Near the start of this template, call this code:

$faceted_search = bang_faceted_search(null, array(
  'force' => array(
    'post_type' => 'product'
  )
));

Later on, display the results with something like:

if ($faceted_search->has_posts()) {
  echo "<h1>Search results</h1>";
  $faceted_search->write_feedback();

  $posts = $faceted_search->get_posts();
  global $post;
  $original_post = $post;
  foreach ($posts as $post) {
    setup_postdata($post);
    // ... write the post ...
  }
  $post = $original_post;
  setup_postdata($post);
  echo $faceted_search->paginate();
}

What’s wrong with a simple search field?

Nothing, but faceted search makes your search richer.

Faceted search doesn’t replace the normal search field, it complements it. You can have both, without any boundary between them.

What’s a “facet”?

It’s a means of narrowing down search results. A user might want to narrow down by categories or tags, by the author of a post, by the date it was published or by the contents of a taxonomy or custom field.

Why don’t I see any faceted search links?

Make sure to create a search sidebar, and put some widgets into it.

If a facet widget has the Hide empty terms option checked, then that facet may easily disappear from a view when all its links would produce zero results.

Can I put other widgets into the same sidebar as the facet widgets?

Yes. It’s a normal sidebar, you can put any widgets into it.

Can I put facet widets into other sidebars?

If the page you’re on isn’t a search page, facet widgets will be invisible.

Does this work with Relevanssi?

Yes. If you have the Relevanssi plugin switched on at the same time, they’ll cooperate to deliver the best search results.

Does this work with my eCommerce/calendar/reviews/other plugin?

You can make a faceted search on any post type, but it won’t understand any special fields like ‘price’ or ‘score’ if they’re implemented in a non-standard way.

Can I make my own facets? Can I filter the results? Can I change how the plugin works?

Yes, yes and yes.

If you use a plugin that defines its own post types, such as an ecommerce or events calendar plugin, then you might want to make your own facet widgets. Create a WordPress widget and register it in the normal way. Look at the code of the included widgets to get an idea how to implement the links.

There are a lot more actions and filters you can hook into – have a look through the code to find them. Here are just a few of them:

• bang_fs_query – The parameters to WP_Query
• bang_fs_results – The posts returned
• bang_fs_count – The number of results
• bang_fs_feedback_args – The fields to display in the feedback
• bang_fs_options – The plugin settings

Be aware that the internal workings of the plugin are subject to change, so the names and details of these hooks may change in future version.

2.0

• Settings page makes this plugin suitable for non-developers
• Simplified widgets by moving common options to the settings page
• Auto switch between a list and a dropdown based on number of options
• Updates to work with WordPress 3.8+
• Better integration with Relevanssi and other plugins
• WPMU: Network Search allows you to search between the sites on your network

1.0

• First version