JSON Search Data Feed Plugin for Wordpress

search-data-feed.php

<?php
/*
Plugin Name: WPSE Search Data Feed
Plugin URI: http://wordpress.stackexchange.com
Description: Provides interface to search and get result in JSON data
Author: Sisir
Version: 1.0
Author URI: http://developerpage.net
*/

add_action('wp_ajax_nopriv_wpse144893_search', 'wpse144893_search_data'); // allow logged out users
add_action('wp_ajax_wpse144893_search', 'wpse144893_search_data'); // allow logged in users

function wpse144893_search_data(){

    $errors = array();
    $data = array(
        'status' => 'error',
        'message' => '',
        'result' => array()
    );

    if(!isset($_REQUEST['term']) || empty($_REQUEST['term']))
        $errors[] = 'No search term given!';


    if(!isset($_REQUEST['limit']) || empty($_REQUEST['limit']))
        $limit = 10;
    else
        $limit = (int) $_REQUEST['limit'];

    if(empty($errors)){

        $term = sanitize_text_field($_REQUEST['term']);

        // setup query data
        $args = array(
            'posts_per_page' => $limit,
            's' => $term
        );

        $query = new WP_Query($args); // run query

        $results = array();
        if($query->have_posts()): while($query->have_posts()): $query->the_post();
            $post_item = array(
                'title' => get_the_title(),
                'excerpt' => get_the_excerpt(),
                'permalink' => get_permalink()
            );
            $results[] = $post_item;
        endwhile;
            $data['status'] = 'success';
            $data['message'] = 'Results found!';
            $data['result'] = $results;
        else:
            $errors[] = 'No post found!';
            $data['message'] = $errors;
        endif;
    }

    echo json_encode($data); // print json

    die(); // kill the script
}