使用ajax，php到jquery获取wordpress posts数组

I am trying to write some code to retrieve wordpress posts to jquery using Ajax

I am just learning so have been alerting to the screen. This is what i have so far:

test.js

  jQuery(document).ready(function($){
   var test_name = "testname";    
   $.ajax({
     url:'/wp-content/plugins/myPlugin/test.php',
     data: {name:test_name},
     type: 'POST',
     cache: false,
     success: function(data){
       alert(data);
     },
     error: function(data){
       alert('something went wrong');           
     }
   });
});

test.php

<?php
$post_args = array(
    'post_type'  => 'products',
    'numberposts' => -1
);
$myProducts = get_posts($post_args);
echo $myProducts;
?>

Can someone point me in the right direction, I can receive strings back from the test.php, so i know the test.php file is being processed. Thank you for any help/explanations

I believe I have got the solution I was looking for, thank you for pointing me towards the admin-ajax.php. Here is the code (not complete but good starter):

test.js

   var wpajax_url = document.location.protocol + '//' + document.location.host + '/wp-admin/admin-ajax.php?action=myAction';

   var myPostType = "products";

   $.ajax({
     'method':'post',
     'url':wpajax_url,
     'data': {aPostType: myPostType},
     'datatype':'json', 
     'cache': false,
     'success': function(data){
       alert(data);
     },
     'error': function(data){
       alert('something went wrong');
     }
   });

test.php

//register myAction with wordpress
add_action('wp_ajax_nopriv_myAction','myAction';
add_action('wp_ajax_myAction','myAction');

function myAction(){
        $post_args = array(
                'post_type'  => $_POST['aPostType'],
                'numberposts' => -1
        );

        $posts = get_posts( $post_args );

        foreach ( $posts as $key => $post) {
            $postArray[$key]= $post->post_title;
        }
        // return result as json
       $json_result = json_encode( $postArray );
       die( $json_result );
}

Hope this can help someone else