PHP Simple router

php-simple-router.php

<?php

$ROUTES = [
  'GET' => [
    'home' => 'Home::index',
    'ping' => 'Session::getPing',
  ],
  'POST' => [
    'ping' => 'Session::postPing',
  ]
];

$parse_url = parse_url( $_SERVER['REQUEST_URI'] );
if($parse_url['path']==='/') { $parse_url['path']='/home'; }

$url = $parse_url;
$url['path'] =  rtrim( $url['path'], '/' );
if($url['path']=='') { $url['path']='/home'; }

if(isset($url['query'])) {
  parse_str( $url['query'], $url['params'] );
}
$url['crumbs'] = explode('/', trim($url['path'],'/'));

$method = strtoupper($_SERVER['REQUEST_METHOD']);
$url['method'] = $method;
$_action = $url['crumbs'][0];
if(isset($ROUTES[$url['method']]) && isset($ROUTES[$url['method']][$_action])) {
  $action = $ROUTES[$url['method']][$_action];
  if($action) {
    $p = explode('::', $action);
    $controller_file_name = __DIR__ . "lib/controller/{$p[0]}Controller.php";
    if(file_exists($controller_file_name)) {
      require_once($controller_file_name);
      $response = call_user_func($action, $url);
      echo $response;
    } else {
      throw new Exception("Not Implemented", 501);
    }
  } else {
    throw new Exception("Method Not Allowed", 405);
  }
} else {
  throw new Exception("Not Found", 404);
}
die;