WordPress AJAX check permission

ajax-permission.php

// if both logged in and not logged in users can send this AJAX request,
// add both of these actions, otherwise add only the appropriate one
add_action( 'wp_ajax_nopriv_myajax-submit', 'myajax_submit' );
add_action( 'wp_ajax_myajax-submit', 'myajax_submit' );

function myajax_submit() {

	$nonce = $_POST['postCommentNonce'];

	// check to see if the submitted nonce matches with the
	// generated nonce we created earlier
	if ( ! wp_verify_nonce( $nonce, 'myajax-post-comment-nonce' ) )
		die ( 'Busted!')

	// ignore the request if the current user doesn't have
	// sufficient permissions
	if ( current_user_can( 'edit_posts' ) ) {
		// get the submitted parameters
		$postID = $_POST['postID'];

		// generate the response
		$response = json_encode( array( 'success' => true ) );

		// response output
		header( "Content-Type: application/json" );
		echo $response;
	}

	// IMPORTANT: don't forget to "exit"
	exit;
}