CodeIgniter 3 request Helper [GET | POST | REQUEST | SERVER]

request_helper.php

<?php 
/**
 * I made this file just for make things easier 
 * 
 * Sometimes I just dont like how CI Input Class works. $this->input->[method] is just too long for me
 * So, with this helper it could be simple just see @example 
 * And this helper also have function for output JSON .. 
 * 
 * @example $username = request("username","POST"); 
 * // it will empty if the request variable is not set
 * @author Herlangga Sefani Wijaya | 6 Feb 2020
 */

/**
 * get HTTP request from $_POST, $_GET, $_REQUEST, $_SERVER
 * 
 * @param String $req_var = Request Variable 
 * @param String $req_method = Request Method (POST/GET/REQUEST/SERVER) default AUTO
 * @return String empty string if no Request Variable registered
 */
function request(String $req_var, String $req_method="AUTO"){
  $ret = "";
  if(strtoupper($req_method) === "POST"){
    $ret = empty($_POST[$req_var]) ? "" : $_POST[$req_var];
  }
  else if(strtoupper($req_method) === "GET"){
    $ret = empty($_GET[$req_var]) ? "" : $_GET[$req_var];
  }
  else if(strtoupper($req_method) === "REQUEST"){
    $ret = empty($_REQUEST[$req_var]) ? "" : $_REQUEST[$req_var];
  }
  else if(strtoupper($req_method) === "SERVER"){
    $ret = empty($_SERVER[$req_var]) ? "" : $_SERVER[$req_var];
  }
  else if(strtoupper($req_method) === "AUTO"){
    if(!empty($_POST[$req_var])){
      $ret = $_POST[$req_var];
    }
    else if(!empty($_GET[$req_var])){
      $ret = $_GET[$req_var];
    }
    else if(!empty($_REQUEST[$req_var])){
      $ret = $_REQUEST[$req_var];
    }
    else if(!empty($_SERVER[$req_var])){
      $ret = $_SERVER[$req_var];
    }
  }
  return $ret;
}

/**
 * Handle Output for JSON 
 * 
 * @param Array $output = Output array for printed as JSON
 */
function output_json(Array $output=[]){
  $CI =& get_instance();
  if(ENVIRONMENT === "development"){
    $output["request"] = $_REQUEST;
  }
  $CI->output->set_content_type("application/json")->set_output(json_encode($output));
}

/* End of file application/helpers/request_helper.php */