aizatto

WP Ajax Query allows you to query your WordPress database using the same query paramaters you would use for WP_Query, and return a JSON respresentation of the query results. This allows developers to easily interface with WordPress without having to relearn a new API.
<h3>How It Works</h3>
The Ajax Query interface would be available at http://example.com/wp-admin/admin-ajax.php?action=query
A sample jQuery request would be like: 
 $.get(ajaxurl, { action: ‘query’ }, function () { }, ‘json’);
Querying for a post: 
 $.get(ajaxurl, { action: ‘query’, p: 1 }, function () { }, ‘json’);
JSON results: 
 { 
 “id”: 1, 
 “type”: ‘post’, 
 “title”: “Hello World”, 
 “permalink”: “http:\/\/example.com\/?p=1” 
 }
Query a category: 
 $.get(ajaxurl, { action: ‘query’, cat: 1 }, function () { }, ‘json’);
JSON results: 
 { 
 “id”: 1 
 “type”: “category”, 
 “permalink”: “http:\/\/example.com\/?cat=1”, 
 “terms”: [], 
 “posts”: [] 
 }
<pre><code>terms and `posts` represents an array of either terms that are sub categories of the category, or posts belonging to the category.<h3>Why I Created It</h3>
</code></pre>
Needed a common way to query the database for posts and taxonomies across multiple plugins, and didn’t find a suitable replacement.

WP Ajax Query

WP Ajax Query allows you to query your WordPress database using the same query paramaters you would use for WP_Query, and return a JSON respresentatio …

Stanislav Khromov

This plugin provides JSON and XML output formats for Toolset Views.
The plugin will also fetch all available custom fields for each post, making it truly simple to integrate WordPress 
with other systems that speak JSON and XML.
New in version 2.0
This plugin now supports Taxonomy and User queries!
Usage
Basic usage
Create your View, go to Settings -> Views Output Formats and pick your format. You will get a link to the XML or JSON version of the query.
<h3>Requirements</h3>
<ul>
<li>PHP 5.3 or higher</li>
</ul>
<h3>Translations</h3>
<ul>
<li>None</li>
</ul>
<h3>Upcoming features</h3>
Support for attaching taxonomy data to posts is planned
Feel free to contribute over at GitHub: 
https://github.com/khromov/wp-views-output-formats

Views Output Formats

Export your WordPress data in XML and JSON formats easily!

WP Ajax Query vs Views Output Formats