horike

We adopted the Elasticsearch to search engine. You can also search, such as post title, post content, custom fields by replacing the WordPress of standard search function. The accuracy of the search feature dramatically improves in WordPress.
<h4>Setting</h4>
<ul>
<li>In the <a href="https://wordpress.org/plugins/wp-simple-elasticsearch/screenshots/" rel="ugc">screenshoot section</a> you can look on the first screenshot. </li>
<li>Require setting to <code>Elasticsearch Endpoint</code>,<code>Port</code>,<code>index</code>,<code>type</code> and push <code>Save Changes</code>. It is default search target <code>post title</code>, <code>post content</code>.</li>
<li>Please push <code>Post Data sync to Elasticsearch</code>. So Posts data are sent to Elasticsearch.</li>
</ul>

WP Simple Elasticsearch

This plugin is that WordPress of standard search using ?s=xxx to replace WordPress DB with Elasticsearch.

Paris Holley

This plugin is NOT a simple drop-in, it is expected you have some understanding of what an ElasticSearch server is and how it works. The goals/features of this plugin are:
<ul>
<li>Replace default wordpress search functionality with that of an ElasticSearch server.</li>
<li>Ability to specify what data points should be indexed and what the relevancy of those points are.</li>
<li>Fall back to default wordpress search if ElasticSearch server is not responsive.</li>
<li>Update ElasticSearch server when posts are removed/added/unpublished.</li>
<li>Provide a faceting API for building your own custom searches</li>
</ul>
Please submit bugs or contributions to the github location and not on wordpress’ system:
https://github.com/parisholley/wordpress-fantastic-elasticsearch/
API/filter/faceting documentation can be found on the wiki:
https://github.com/parisholley/wordpress-fantastic-elasticsearch/wiki

Fantastic ElasticSearch

Improve wordpress search performance/accuracy and enable faceted search by leveraging an ElasticSearch server.

WP Simple Elasticsearch vs Fantastic ElasticSearch