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 . '/http/request.php';
  20 require_once HOPLITE_ROOT . '/http/response.php';
  21 require_once HOPLITE_ROOT . '/http/response_code.php';
  22
  23 /*!
  24   The RootController is meant to be invoked from the index.php of the
  25   application.
  26 */
  27 class RootController
  28 {
  29   /*! @var Request */
  30   private $request = NULL;
  31
  32   /*! @var Response */
  33   private $response = NULL;
  34
  35   /*! @var UrlMap */
  36   private $url_map = NULL;
  37
  38   /*! @var OutputFilter */
  39   private $output_filter = NULL;
  40
  41   /*! @var RootControllerDelegate */
  42   private $delegate = NULL;
  43
  44   /*!
  45     Creates the controller with the request context information, typicallhy
  46     from the global scope ($GLOBALS), but can be injected for testing.
  47     @param UrlMap The routing map
  48     @param OutputFilter The object responsible for decorating output.
  49     @param array& PHP globals array
  50   */
  51   public function __construct(array $globals)
  52   {
  53     $this->response = new Response();
  54     $this->request = new Request();
  55     $this->request->data = array(
  56       '_GET'    => &$globals['_GET'],
  57       '_POST'   => &$globals['_POST'],
  58       '_COOKIE' => &$globals['_COOKIE'],
  59       '_SERVER' => &$globals['_SERVER']
  60     );
  61   }
  62
  63   /*! Accessors */
  64   public function request() { return $this->request; }
  65   public function response() { return $this->response; }
  66
  67   /*! Sets the UrlMap. */
  68   public function set_url_map(UrlMap $url_map) { $this->url_map = $url_map; }
  69
  70   /*! Sest the Output Filter. */
  71   public function set_output_filter(OutputFilter $output_filter)
  72   {
  73     $this->output_filter = $output_filter;
  74   }
  75
  76   /*! Sets the delegate. */
  77   public function set_delegate($delegate)
  78   {
  79     $this->delegate = $delegate;
  80   }
  81   public function delegate()
  82   {
  83     return $this->delegate;
  84   }
  85
  86   /*!
  87     Createst the Request and Response that are used throughout the duration of
  88     the execution.
  89   */
  90   public function Run()
  91   {
  92     // The query rewriter module of the webserver rewrites a request from:
  93     //    http://example.com/webapp/user/view/42
  94     // to:
  95     //    http://example.com/webapp/index.php/user/view/42
  96     // ... which then becomes accessible from PATH_INFO.
  97     $data = $this->request->data['_SERVER'];
  98     if (isset($data['PATH_INFO']))
  99       $url = $data['PATH_INFO'];
 100     else
 101       $url = '/';
 102     if ($url[0] == '/')
 103       $url = substr($url, 1);
 104
 105     // Set the final pieces of the request.
 106     $this->request->url = $url;
 107     $this->request->http_method = $this->request->data['_SERVER']['REQUEST_METHOD'];
 108
 109     // Extract any PUT data as POST params.
 110     if ($this->request->http_method == 'PUT')
 111       parse_str(file_get_contents('php://input'), $this->request->data['_POST']);
 112
 113     // Register self as the active instance.
 114     $GLOBALS[__CLASS__] = $this;
 115
 116     if ($this->delegate)
 117       $this->delegate->OnInitialRequest($this->request, $this->response);
 118
 119     // Dispatch the request to an Action.
 120     $this->RouteRequest($this->request);
 121
 122     // When control returns here, all actions have been invoked and it's time
 123     // to start the output filter and exit.
 124     $this->Stop();
 125   }
 126
 127   /*!
 128     Prevents any other Actions from executing. This starts the OutputFilter and
 129     then exits.
 130   */
 131   public function Stop()
 132   {
 133     if ($this->delegate)
 134       $this->delegate->WillStop($this->request, $this->response);
 135     $this->output_filter->FilterOutput($this->request, $this->response);
 136     $this->_Exit();
 137   }
 138
 139   /*!
 140     Sets the response code and stops the controller. Returns void.
 141   */
 142   public function StopWithCode($code)
 143   {
 144     $this->response->response_code = $code;
 145     $this->Stop();
 146   }
 147
 148   /*!
 149     Sets the response code to HTTP 302 FOUND and redirects the page to a new
 150     location.
 151     @param string The destination location of the redirect.
 152   */
 153   public function StopWithRedirect($location)
 154   {
 155     $this->response->headers['Location'] = $location;
 156     $this->StopWithCode(ResponseCode::FOUND);
 157   }
 158
 159
 160   /*!
 161     Wrapper around PHP exit().
 162   */
 163   protected function _Exit()
 164   {
 165     exit;
 166   }
 167
 168   /*!
 169     Invoked by Run() and can be invoked by others to evaluate and perform the
 170     lookup in the UrlMap. This then calls InvokeAction().
 171     @param Request The Request whose URL will be routed
 172   */
 173   public function RouteRequest(Request $request)
 174   {
 175     if ($this->delegate)
 176       $this->delegate->WillRouteRequest($request, $this->response);
 177
 178     $url_map_value = $this->url_map->Evaluate($request);
 179
 180     $action = NULL;
 181     if ($url_map_value)
 182       $action = $this->url_map->LookupAction($url_map_value);
 183
 184     if (!$action) {
 185       $this->response->response_code = ResponseCode::NOT_FOUND;
 186       $this->Stop();
 187       return;
 188     }
 189
 190     $this->InvokeAction($action);
 191   }
 192
 193   /*!
 194     Used to run an Action and drive it through its states.
 195     @param Action
 196   */
 197   public function InvokeAction(Action $action)
 198   {
 199     if ($this->delegate)
 200       $this->delegate->WillInvokeAction($action, $this->request, $this->response);
 201
 202     $action->FilterRequest($this->request, $this->response);
 203     $action->Invoke($this->request, $this->response);
 204     $action->FilterResponse($this->request, $this->response);
 205
 206     if ($this->delegate)
 207       $this->delegate->DidInvokeAction($action, $this->request, $this->response);
 208   }
 209
 210   /*!
 211     Performs a reverse-lookup in the UrlMap for the pattern/fragment for the
 212     name of a given Action class.
 213     @param string Class name.
 214   */
 215   public function LookupAction($class)
 216   {
 217     $map = $this->url_map->map();
 218     foreach ($map as $pattern => $action) {
 219       if ($action == $class)
 220         return $pattern;
 221     }
 222   }
 223
 224   /*!
 225     Given a relative path, return an absolute path from the root controller.
 226     @param string The relative path for which a URL will be created
 227     @param bool Include the HTTP scheme and host to create an RFC URL if true;
 228                 if false an absolute path will be returned.
 229   */
 230   public function MakeURL($new_path, $url = FALSE)
 231   {
 232     // Detect the common paths between the REQUEST_URI and the PATH_INFO. That
 233     // common piece will be the path to the root controller.
 234     $request_uri = $this->request()->data['_SERVER']['REQUEST_URI'];
 235     $path_info = $this->request()->data['_SERVER']['PATH_INFO'];
 236     if ($path_info === NULL)
 237       $common_uri = substr($request_uri, 0, -1);
 238     else
 239       $common_uri = strstr($request_uri, $path_info, TRUE);
 240
 241     // If just constructing an absolute path, return that now.
 242     if (!$url)
 243       return $common_uri . $new_path;
 244
 245     // Otherwise, build the host part.
 246     $url = 'http';
 247     if (isset($this->request()->data['_SERVER']['HTTPS']) &&
 248         $this->request()->data['_SERVER']['HTTPS'] == 'on') {
 249       $url .= 's';
 250     }
 251     $url .= '://' . $this->request()->data['_SERVER']['HTTP_HOST'];
 252
 253     $port = $this->request()->data['_SERVER']['SERVER_PORT'];
 254     if ($port != 80 && $port != 443)
 255       $url .= ':' . $port;
 256
 257     $url .= $common_uri;
 258     return $url . $new_path;
 259   }
 260 }
 261
 262 /*!
 263   Delegate for the root controller. All methods are optional.
 264 */
 265 interface RootControllerDelegate
 266 {
 267   public function OnInitialRequest(Request $request, Response $response);
 268
 269   public function WillRouteRequest(Request $request, Response $response);
 270
 271   public function WillInvokeAction(Action $action, Request $request, Response $response);
 272
 273   public function DidInvokeAction(Action $action, Request $request, Response $response);
 274
 275   public function WillStop(Request $request, Response $response);
 276 }