http/root_controller.php

   1 <?php
   2 // Hoplite
   3 // Copyright (c) 2011 Blue Static
   4 //
   5 // This program is free software: you can redistribute it and/or modify it
   6 // under the terms of the GNU General Public License as published by the Free
   7 // Software Foundation, either version 3 of the License, or any later version.
   8 //
   9 // This program is distributed in the hope that it will be useful, but WITHOUT
  10 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 // FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12 // more details.
  13 //
  14 // You should have received a copy of the GNU General Public License along with
  15 // this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 namespace hoplite\http;
  18
  19 require_once HOPLITE_ROOT . '/base/weak_interface.php';
  20 require_once HOPLITE_ROOT . '/http/request.php';
  21 require_once HOPLITE_ROOT . '/http/response.php';
  22 require_once HOPLITE_ROOT . '/http/response_code.php';
  23
  24 /*!
  25   The RootController is meant to be invoked from the index.php of the
  26   application.
  27 */
  28 class RootController
  29 {
  30   /*! @var Request */
  31   private $request = NULL;
  32
  33   /*! @var Response */
  34   private $response = NULL;
  35
  36   /*! @var UrlMap */
  37   private $url_map = NULL;
  38
  39   /*! @var OutputFilter */
  40   private $output_filter = NULL;
  41
  42   /*! @var WeakInterface<RootControllerDelegate> */
  43   private $delegate = NULL;
  44
  45   /*!
  46     Creates the controller with the request context information, typicallhy
  47     from the global scope ($GLOBALS), but can be injected for testing.
  48     @param UrlMap The routing map
  49     @param OutputFilter The object responsible for decorating output.
  50     @param array& PHP globals array
  51   */
  52   public function __construct(array $globals)
  53   {
  54     $this->response = new Response();
  55     $this->request = new Request();
  56     $this->request->data = array(
  57       '_GET'    => &$globals['_GET'],
  58       '_POST'   => &$globals['_POST'],
  59       '_COOKIE' => &$globals['_COOKIE'],
  60       '_SERVER' => &$globals['_SERVER']
  61     );
  62     $this->delegate = new \hoplite\base\WeakInterface('hoplite\http\RootControllerDelegate');
  63   }
  64
  65   /*! Accessors */
  66   public function request() { return $this->request; }
  67   public function response() { return $this->response; }
  68
  69   /*! Sets the UrlMap. */
  70   public function set_url_map(UrlMap $url_map) { $this->url_map = $url_map; }
  71
  72   /*! Sest the Output Filter. */
  73   public function set_output_filter(OutputFilter $output_filter)
  74   {
  75     $this->output_filter = $output_filter;
  76   }
  77
  78   /*! Sets the delegate. */
  79   public function set_delegate($delegate)
  80   {
  81     $this->delegate->Bind($delegate);
  82   }
  83
  84   /*!
  85     Createst the Request and Response that are used throughout the duration of
  86     the execution.
  87   */
  88   public function Run()
  89   {
  90     // The query rewriter module of the webserver rewrites a request from:
  91     //    http://example.com/webapp/user/view/42
  92     // to:
  93     //    http://example.com/webapp/index.php/user/view/42
  94     // ... which then becomes accessible from PATH_INFO.
  95     $data = $this->request->data['_SERVER'];
  96     if (isset($data['PATH_INFO']))
  97       $url = $data['PATH_INFO'];
  98     else
  99       $url = '/';
 100     if ($url[0] == '/')
 101       $url = substr($url, 1);
 102
 103     // Set the final pieces of the request.
 104     $this->request->url = $url;
 105     $this->request->http_method = $this->request->data['_SERVER']['REQUEST_METHOD'];
 106
 107     $this->delegate->OnInitialRequest($this->request, $this->response);
 108
 109     // Dispatch the request to an Action.
 110     $this->RouteRequest($this->request);
 111
 112     // When control returns here, all actions have been invoked and it's time
 113     // to start the output filter and exit.
 114     $this->Stop();
 115   }
 116
 117   /*!
 118     Prevents any other Actions from executing. This starts the OutputFilter and
 119     then exits.
 120   */
 121   public function Stop()
 122   {
 123     $this->delegate->WillStop($this->request, $this->response);
 124     $this->output_filter->FilterOutput($this->request, $this->response);
 125     $this->_Exit();
 126   }
 127
 128   /*!
 129     Wrapper around PHP exit().
 130   */
 131   protected function _Exit()
 132   {
 133     exit;
 134   }
 135
 136   /*!
 137     Invoked by Run() and can be invoked by others to evaluate and perform the
 138     lookup in the UrlMap. This then calls InvokeAction().
 139     @param Request The Request whose URL will be routed
 140   */
 141   public function RouteRequest(Request $request)
 142   {
 143     $this->delegate->WillRouteRequest($request, $this->response);
 144
 145     $url_map_value = $this->url_map->Evaluate($request);
 146
 147     $action = NULL;
 148     if ($url_map_value)
 149       $action = $this->url_map->LookupAction($url_map_value);
 150
 151     if (!$action) {
 152       $this->response->response_code = ResponseCode::NOT_FOUND;
 153       $this->Stop();
 154       return;
 155     }
 156
 157     $this->InvokeAction($action);
 158   }
 159
 160   /*!
 161     Used to run an Action and drive it through its states.
 162     @param Action
 163   */
 164   public function InvokeAction(Action $action)
 165   {
 166     $this->delegate->WillInvokeAction($action, $this->request, $this->response);
 167
 168     $action->FilterRequest($this->request, $this->response);
 169     $action->Invoke($this->request, $this->response);
 170     $action->FilterResponse($this->request, $this->response);
 171
 172     $this->delegate->DidInvokeAction($action, $this->request, $this->response);
 173   }
 174
 175   /*!
 176     Performs a reverse-lookup in the UrlMap for the pattern/fragment for the
 177     name of a given Action class.
 178     @param string Class name.
 179   */
 180   public function LookupAction($class)
 181   {
 182     $map = $this->url_map->map();
 183     foreach ($map as $pattern => $action) {
 184       if ($action == $class)
 185         return $pattern;
 186     }
 187   }
 188
 189   /*!
 190     Given a relative path, return an absolute path from the root controller.
 191     @param string The relative path for which a URL will be created
 192     @param bool Include the HTTP scheme and host to create an RFC URL if true;
 193                 if false an absolute path will be returned.
 194   */
 195   public function MakeURL($new_path, $url = FALSE)
 196   {
 197     // Detect the common paths between the REQUEST_URI and the PATH_INFO. That
 198     // common piece will be the path to the root controller.
 199     $request_uri = $this->request()->data['_SERVER']['REQUEST_URI'];
 200     $path_info = $this->request()->data['_SERVER']['PATH_INFO'];
 201     $common_uri = strstr($request_uri, $path_info, TRUE);
 202
 203     // If just constructing an absolute path, return that now.
 204     if (!$url)
 205       return $common_uri . $new_path;
 206
 207     // Otherwise, build the host part.
 208     $url = 'http';
 209     if (isset($this->request()->data['_SERVER']['HTTPS']) &&
 210         $this->request()->data['_SERVER']['HTTPS'] == 'on') {
 211       $url .= 's';
 212     }
 213     $url .= '://' . $this->request()->data['_SERVER']['HTTP_HOST'];
 214
 215     $port = $this->request()->data['_SERVER']['SERVER_PORT'];
 216     if ($port != 80 && $port != 443)
 217       $url .= ':' . $port;
 218
 219     $url .= $common_uri;
 220     return $url . $new_path;
 221   }
 222 }
 223
 224 /*!
 225   Delegate for the root controller. The controller uses WeakInterface to call
 226   these methods, so they're all optional.
 227 */
 228 interface RootControllerDelegate
 229 {
 230   public function OnInitialRequest(Request $request, Response $response);
 231
 232   public function WillRouteRequest(Request $request, Response $response);
 233
 234   public function WillInvokeAction(Action $action, Request $request, Response $response);
 235
 236   public function DidInvokeAction(Action $action, Request $request, Response $response);
 237
 238   public function WillStop(Request $request, Response $response);
 239 }