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 = $this->request->data['_SERVER']['REQUEST_METHOD'];
 106
 107     // Extract any PUT data as POST params.
 108     if ($this->request->http_method == 'PUT')
 109       parse_str(file_get_contents('php://input'), $this->request->data['_POST']);
 110
 111     // Register self as the active instance.
 112     $GLOBALS[__CLASS__] = $this;
 113
 114     $this->delegate->OnInitialRequest($this->request, $this->response);
 115
 116     // Dispatch the request to an Action.
 117     $this->RouteRequest($this->request);
 118
 119     // When control returns here, all actions have been invoked and it's time
 120     // to start the output filter and exit.
 121     $this->Stop();
 122   }
 123
 124   /*!
 125     Prevents any other Actions from executing. This starts the OutputFilter and
 126     then exits.
 127   */
 128   public function Stop()
 129   {
 130     $this->delegate->WillStop($this->request, $this->response);
 131     $this->output_filter->FilterOutput($this->request, $this->response);
 132     $this->_Exit();
 133   }
 134
 135   /*!
 136     Wrapper around PHP exit().
 137   */
 138   protected function _Exit()
 139   {
 140     exit;
 141   }
 142
 143   /*!
 144     Invoked by Run() and can be invoked by others to evaluate and perform the
 145     lookup in the UrlMap. This then calls InvokeAction().
 146     @param Request The Request whose URL will be routed
 147   */
 148   public function RouteRequest(Request $request)
 149   {
 150     $this->delegate->WillRouteRequest($request, $this->response);
 151
 152     $url_map_value = $this->url_map->Evaluate($request);
 153
 154     $action = NULL;
 155     if ($url_map_value)
 156       $action = $this->url_map->LookupAction($url_map_value);
 157
 158     if (!$action) {
 159       $this->response->response_code = ResponseCode::NOT_FOUND;
 160       $this->Stop();
 161       return;
 162     }
 163
 164     $this->InvokeAction($action);
 165   }
 166
 167   /*!
 168     Used to run an Action and drive it through its states.
 169     @param Action
 170   */
 171   public function InvokeAction(Action $action)
 172   {
 173     $this->delegate->WillInvokeAction($action, $this->request, $this->response);
 174
 175     $action->FilterRequest($this->request, $this->response);
 176     $action->Invoke($this->request, $this->response);
 177     $action->FilterResponse($this->request, $this->response);
 178
 179     $this->delegate->DidInvokeAction($action, $this->request, $this->response);
 180   }
 181
 182   /*!
 183     Performs a reverse-lookup in the UrlMap for the pattern/fragment for the
 184     name of a given Action class.
 185     @param string Class name.
 186   */
 187   public function LookupAction($class)
 188   {
 189     $map = $this->url_map->map();
 190     foreach ($map as $pattern => $action) {
 191       if ($action == $class)
 192         return $pattern;
 193     }
 194   }
 195
 196   /*!
 197     Given a relative path, return an absolute path from the root controller.
 198     @param string The relative path for which a URL will be created
 199     @param bool Include the HTTP scheme and host to create an RFC URL if true;
 200                 if false an absolute path will be returned.
 201   */
 202   public function MakeURL($new_path, $url = FALSE)
 203   {
 204     // Detect the common paths between the REQUEST_URI and the PATH_INFO. That
 205     // common piece will be the path to the root controller.
 206     $request_uri = $this->request()->data['_SERVER']['REQUEST_URI'];
 207     $path_info = $this->request()->data['_SERVER']['PATH_INFO'];
 208     $common_uri = strstr($request_uri, $path_info, TRUE);
 209
 210     // If just constructing an absolute path, return that now.
 211     if (!$url)
 212       return $common_uri . $new_path;
 213
 214     // Otherwise, build the host part.
 215     $url = 'http';
 216     if (isset($this->request()->data['_SERVER']['HTTPS']) &&
 217         $this->request()->data['_SERVER']['HTTPS'] == 'on') {
 218       $url .= 's';
 219     }
 220     $url .= '://' . $this->request()->data['_SERVER']['HTTP_HOST'];
 221
 222     $port = $this->request()->data['_SERVER']['SERVER_PORT'];
 223     if ($port != 80 && $port != 443)
 224       $url .= ':' . $port;
 225
 226     $url .= $common_uri;
 227     return $url . $new_path;
 228   }
 229 }
 230
 231 /*!
 232   Delegate for the root controller. The controller uses WeakInterface to call
 233   these methods, so they're all optional.
 234 */
 235 interface RootControllerDelegate
 236 {
 237   public function OnInitialRequest(Request $request, Response $response);
 238
 239   public function WillRouteRequest(Request $request, Response $response);
 240
 241   public function WillInvokeAction(Action $action, Request $request, Response $response);
 242
 243   public function DidInvokeAction(Action $action, Request $request, Response $response);
 244
 245   public function WillStop(Request $request, Response $response);
 246 }