CodeIgniter input class, implementing PATCH and DELETE HTTP request methods

MY_Input.php

<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class MY_Input extends CI_Input {
	protected $raw;
	protected $delete;
	protected $patch;

	public function __construct() {
		parent::__construct();
		
		$this->raw = file_get_contents('php://input');
	
		if ( !empty($this->raw) ) {
			if ( $this->request_method() == 'DELETE' ) {
				$this->delete = $this->_sanitize_request($this->raw);
			} else if ( $this->request_method() == 'PATCH' ) {
				$this->patch = $this->_sanitize_request($this->raw);
			}
		}
	}

	public function request_method() {
		return strtoupper($this->server('REQUEST_METHOD'));
	}

	public function patch($index = NULL, $xss_clean = FALSE) {
		if ($index === NULL AND ! empty($this->patch) ) {
			$patch = array();
 
			foreach (array_keys($this->patch) as $key) {
				$patch[$key] = $this->_fetch_from_array($this->patch, $key, $xss_clean);
			}

			return $patch;
		}
 
		return $this->_fetch_from_array($this->patch, $index, $xss_clean);
	}

	public function delete($index = NULL, $xss_clean = FALSE) {
		if ($index === NULL AND ! empty($this->delete) ) {
			$delete = array();
 
			foreach (array_keys($this->delete) as $key) {
				$delete[$key] = $this->_fetch_from_array($this->delete, $key, $xss_clean);
			}

			return $delete;
		}
 
		return $this->_fetch_from_array($this->delete, $index, $xss_clean);
	}

	private function _sanitize_request($raw) {
		$object = json_decode($raw, TRUE);
		$data = array();

		if ( is_array($object) ) {
			foreach( $object as $key => &$val) {
				if(!is_object($val) ) {
					$data[$this->_clean_input_keys($key)] = $this->_clean_input_data($val);
				}
			}

			unset($val);
		}

		return $data;
	}
}