<form method="POST">
    <h3>Editing: wp-async-request.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
/**
 * WP Async Request
 *
 * @package WP-Background-Processing
 */

defined( 'ABSPATH' ) || exit;

/**
 * Abstract WP_Async_Request class.
 */
abstract class WP_Async_Request {

	/**
	 * Prefix
	 *
	 * (default value: 'wp')
	 *
	 * @var string
	 * @access protected
	 */
	protected $prefix = 'wp';

	/**
	 * Action
	 *
	 * (default value: 'async_request')
	 *
	 * @var string
	 * @access protected
	 */
	protected $action = 'async_request';

	/**
	 * Identifier
	 *
	 * @var mixed
	 * @access protected
	 */
	protected $identifier;

	/**
	 * Data
	 *
	 * (default value: array())
	 *
	 * @var array
	 * @access protected
	 */
	protected $data = array();

	/**
	 * Initiate new async request
	 */
	public function __construct() {
		$this-&gt;identifier = $this-&gt;prefix . '_' . $this-&gt;action;

		add_action( 'wp_ajax_' . $this-&gt;identifier, array( $this, 'maybe_handle' ) );
		add_action( 'wp_ajax_nopriv_' . $this-&gt;identifier, array( $this, 'maybe_handle' ) );
	}

	/**
	 * Set data used during the request
	 *
	 * @param array $data Data.
	 *
	 * @return $this
	 */
	public function data( $data ) {
		$this-&gt;data = $data;

		return $this;
	}

	/**
	 * Dispatch the async request
	 *
	 * @return array|WP_Error
	 */
	public function dispatch() {
		$url  = add_query_arg( $this-&gt;get_query_args(), $this-&gt;get_query_url() );
		$args = $this-&gt;get_post_args();

		return wp_remote_post( esc_url_raw( $url ), $args );
	}

	/**
	 * Get query args
	 *
	 * @return array
	 */
	protected function get_query_args() {
		if ( property_exists( $this, 'query_args' ) ) {
			return $this-&gt;query_args;
		}

		return array(
			'action' =&gt; $this-&gt;identifier,
			'nonce'  =&gt; wp_create_nonce( $this-&gt;identifier ),
		);
	}

	/**
	 * Get query URL
	 *
	 * @return string
	 */
	protected function get_query_url() {
		if ( property_exists( $this, 'query_url' ) ) {
			return $this-&gt;query_url;
		}

		return admin_url( 'admin-ajax.php' );
	}

	/**
	 * Get post args
	 *
	 * @return array
	 */
	protected function get_post_args() {
		if ( property_exists( $this, 'post_args' ) ) {
			return $this-&gt;post_args;
		}

		return array(
			'timeout'   =&gt; 0.01,
			'blocking'  =&gt; false,
			'body'      =&gt; $this-&gt;data,
			'cookies'   =&gt; $_COOKIE,
			'sslverify' =&gt; apply_filters( 'https_local_ssl_verify', false ),
		);
	}

	/**
	 * Maybe handle
	 *
	 * Check for correct nonce and pass to handler.
	 */
	public function maybe_handle() {
		// Don't lock up other requests while processing
		session_write_close();

		check_ajax_referer( $this-&gt;identifier, 'nonce' );

		$this-&gt;handle();

		wp_die();
	}

	/**
	 * Handle
	 *
	 * Override this method to perform any actions required
	 * during the async request.
	 */
	abstract protected function handle();

}
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