[PHP] CodeIgniter4 Controllers 알아보기

CodeIgniter 4.1.1 의 컨트롤러 분석

 

심심해서 해보는 거라 그냥 참고만 하면 될 듯 싶다.

하지만 피드백을 주신다면 항상 감사합니다.

 

코드이그나이터는 컴포저로 파일을 받아와서 

rewrite.php를 시작으로 index.php 를 불러온다.

 

index.php

// Valid PHP Version?
$minPHPVersion = '7.3';
if (version_compare(PHP_VERSION, $minPHPVersion, '<'))
{
	die("Your PHP version must be {$minPHPVersion} or higher to run CodeIgniter. Current version: " . PHP_VERSION);
}
unset($minPHPVersion);

// Path to the front controller (this file)
define('FCPATH', __DIR__ . DIRECTORY_SEPARATOR);

/*
 *---------------------------------------------------------------
 * BOOTSTRAP THE APPLICATION
 *---------------------------------------------------------------
 * This process sets up the path constants, loads and registers
 * our autoloader, along with Composer's, loads our constants
 * and fires up an environment-specific bootstrapping.
 */

// Ensure the current directory is pointing to the front controller's directory
chdir(__DIR__);

// Load our paths config file
// This is the line that might need to be changed, depending on your folder structure.
require realpath(FCPATH . '../app/Config/Paths.php') ?: FCPATH . '../app/Config/Paths.php';
// ^^^ Change this if you move your application folder

$paths = new Config\Paths();

// Location of the framework bootstrap file.
$bootstrap = rtrim($paths->systemDirectory, '\\/ ') . DIRECTORY_SEPARATOR . 'bootstrap.php';
$app       = require realpath($bootstrap) ?: $bootstrap;

/*
 *---------------------------------------------------------------
 * LAUNCH THE APPLICATION
 *---------------------------------------------------------------
 * Now that everything is setup, it's time to actually fire
 * up the engines and make this app do its thang.
 */
$app->run();

public/index.php의 모든 부분이고 상세한 건 더 봐야겠지만 여기서부터 $app->run() 부분에서 실제 어플리케이션이 시작되는 것 같다.

 

$app->run()의 내부로 들어가게 되면

아래와 같은 코드들을 확인할 수 있는데 꽤 알기좋게 잘 만들어져 있어서 확인이 편하다.

 

run 함수 내부

public function run(RouteCollectionInterface $routes = null, bool $returnResponse = false)
{
  $this->startBenchmark();

  $this->getRequestObject();
  $this->getResponseObject();

  $this->forceSecureAccess();

  $this->spoofRequestMethod();

  Events::trigger('pre_system');

  // Check for a cached page. Execution will stop
  // if the page has been cached.
  $cacheConfig = new Cache();
  $response    = $this->displayCache($cacheConfig);
  if ($response instanceof ResponseInterface)
  {
  	if ($returnResponse)
    {
    	return $response;
    }

    $this->response->pretend($this->useSafeOutput)->send();
    $this->callExit(EXIT_SUCCESS);
    }

  try
  {
  	return $this->handleRequest($routes, $cacheConfig, $returnResponse);
  }
  catch (RedirectException $e)
  {
    $logger = Services::logger();
    $logger->info('REDIRECTED ROUTE at ' . $e->getMessage());

    // If the route is a 'redirect' route, it throws
    // the exception with the $to as the message
    $this->response->redirect(base_url($e->getMessage()), 'auto', $e->getCode());
    $this->sendResponse();

    $this->callExit(EXIT_SUCCESS);
  }
  catch (PageNotFoundException $e)
  {
  $this->display404errors($e);
  }
}

run()의 함수 내부 구조이고 위치는 vendor 폴더에서 codeigniter4/framework/system/Codeigniter.php 에서 확인할 수 있다.

 

return $this->handleRequest($routes, $cacheConfig, $returnResponse);

위 코드블록에서 handleRequest로 들어가면 컨트롤러가 어떻게 만들어져 있는지 확인할 수 있는데,

그전에 tryToRouteIt함수를 통해서 라우팅 과정도 확인할 수 있었다.

 

handleRequest 함수 내부

protected function handleRequest(?RouteCollectionInterface $routes, Cache $cacheConfig, bool $returnResponse = false)
{
  $routeFilter = $this->tryToRouteIt($routes);

  // Run "before" filters
  $filters = Services::filters();

  // If any filters were specified within the routes file,
  // we need to ensure it's active for the current request
  if (! is_null($routeFilter))
  {
  	$filters->enableFilter($routeFilter, 'before');
  	$filters->enableFilter($routeFilter, 'after');
  }

  $uri = $this->request instanceof CLIRequest ? $this->request->getPath() : $this->request->getUri()->getPath();

  // Never run filters when running through Spark cli
  if (! defined('SPARKED'))
  {
    $possibleResponse = $filters->run($uri, 'before');

    // If a ResponseInterface instance is returned then send it back to the client and stop
    if ($possibleResponse instanceof ResponseInterface)
    {
    	return $returnResponse ? $possibleResponse : $possibleResponse->pretend($this->useSafeOutput)->send();
    }

    if ($possibleResponse instanceof Request)
    {
    	$this->request = $possibleResponse;
    }
  }

  $returned = $this->startController();

  // Closure controller has run in startController().
  if (! is_callable($this->controller))
  {
    $controller = $this->createController();

    if (! method_exists($controller, '_remap') && ! is_callable([$controller, $this->method], false))
    {
    	throw PageNotFoundException::forMethodNotFound($this->method);
    }

    	// Is there a "post_controller_constructor" event?
    	Events::trigger('post_controller_constructor');

    	$returned = $this->runController($controller);
    }
    else
    {
    	$this->benchmark->stop('controller_constructor');
    	$this->benchmark->stop('controller');
    }

    // If $returned is a string, then the controller output something,
    // probably a view, instead of echoing it directly. Send it along
    // so it can be used with the output.
    $this->gatherOutput($cacheConfig, $returned);

    // Never run filters when running through Spark cli
    if (! defined('SPARKED'))
    {
      $filters->setResponse($this->response);
      // Run "after" filters
      $response = $filters->run($uri, 'after');
    }
    else
    {
      $response = $this->response;

   	  // Set response code for CLI command failures
      if (is_numeric($returned) || $returned === false)
      {
          $response->setStatusCode(400);
      }
  }

  if ($response instanceof ResponseInterface)
  {
  	$this->response = $response;
  }

  // Save our current URI as the previous URI in the session
  // for safer, more accurate use with `previous_url()` helper function.
  $this->storePreviousURL((string) current_url(true));

  unset($uri);

  if (! $returnResponse)
  {
  	$this->sendResponse();
  }

  //--------------------------------------------------------------------
  // Is there a post-system event?
  //--------------------------------------------------------------------
  Events::trigger('post_system');

  return $this->response;
}

 

여기서 아래 코드에서 컨트롤러가 실행되는 코드인데,

$returned = $this->runController($controller);

 

runController 함수 내부

protected function runController($class)
{
  // If this is a console request then use the input segments as parameters
  $params = defined('SPARKED') ? $this->request->getSegments() : $this->router->params(); // @phpstan-ignore-line

  if (method_exists($class, '_remap'))
  {
  $output = $class->_remap($this->method, ...$params);
  }
  else
  {
  $output = $class->{$this->method}(...$params);
  }

  $this->benchmark->stop('controller');

  return $output;
}

$output 변수가 있는 라인줄에서 개발자가 만들어놓은 컨트롤러 클래스의 함수로 접근하고 있는 것을 확인할 수 있었다.

 

위와 같은 과정은 Xdebug에서 callStack을 확인하면 알 수 있으므로 알아보면 된다.

버전이 바뀌면 위 코드 과정은 비슷하겠지만 코드들은 바뀔 수 있으므로 어떻게 동작하는지만 확인하면 좋을 것 같다.