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     $url = $this->request->data['_SERVER']['PATH_INFO'];
  96     if ($url[0] == '/')
  97       $url = substr($url, 1);
  98
  99     // Set the final pieces of the request.
 100     $this->request->url = $url;
 101     $this->request->http_method = $this->request->data['_SERVER']['REQUEST_METHOD'];
 102
 103     $this->delegate->OnInitialRequest($this->request);
 104
 105     // Dispatch the request to an Action.
 106     $this->RouteRequest($this->request);
 107
 108     // When control returns here, all actions have been invoked and it's time
 109     // to start the output filter and exit.
 110     $this->Stop();
 111   }
 112
 113   /*!
 114     Prevents any other Actions from executing. This starts the OutputFilter and
 115     then exits.
 116   */
 117   public function Stop()
 118   {
 119     $this->delegate->WillStop($this->request, $this->response);
 120     $this->output_filter->FilterOutput($this->request, $this->response);
 121     $this->_Exit();
 122   }
 123
 124   /*!
 125     Wrapper around PHP exit().
 126   */
 127   protected function _Exit()
 128   {
 129     exit;
 130   }
 131
 132   /*!
 133     Invoked by Run() and can be invoked by others to evaluate and perform the
 134     lookup in the UrlMap. This then calls InvokeAction().
 135     @param Request The Request whose URL will be routed
 136   */
 137   public function RouteRequest(Request $request)
 138   {
 139     $this->delegate->WillRouteRequest($request, $this->response);
 140
 141     $url_map_value = $this->url_map->Evaluate($request);
 142
 143     $action = NULL;
 144     if ($url_map_value)
 145       $action = $this->url_map->LookupAction($url_map_value);
 146
 147     if (!$action) {
 148       $this->response->response_code = ResponseCode::NOT_FOUND;
 149       $this->Stop();
 150       return;
 151     }
 152
 153     $this->InvokeAction($action);
 154   }
 155
 156   /*!
 157     Used to run an Action and drive it through its states.
 158     @param Action
 159   */
 160   public function InvokeAction(Action $action)
 161   {
 162     $this->delegate->WillInvokeAction($action, $this->request, $this->response);
 163
 164     $action->FilterRequest($this->request, $this->response);
 165     $action->Invoke($this->request, $this->response);
 166     $action->FilterResponse($this->request, $this->response);
 167
 168     $this->delegate->DidInvokeAction($action, $this->request, $this->response);
 169   }
 170
 171   /*!
 172     Performs a reverse-lookup in the UrlMap for the pattern/fragment for the
 173     name of a given Action class.
 174     @param string Class name.
 175   */
 176   public function LookupAction($class)
 177   {
 178     $map = $this->url_map->map();
 179     foreach ($map as $pattern => $action) {
 180       if ($action == $class)
 181         return $pattern;
 182     }
 183   }
 184 }
 185
 186 /*!
 187   Delegate for the root controller. The controller uses WeakInterface to call
 188   these methods, so they're all optional.
 189 */
 190 interface RootControllerDelegate
 191 {
 192   public function OnInitialRequest(Request $request);
 193
 194   public function WillRouteRequest(Request $request, Response $response);
 195
 196   public function WillInvokeAction(Action $action, Request $request, Response $response);
 197
 198   public function DidInvokeAction(Action $action, Request $request, Response $response);
 199
 200   public function WillStop(Request $request, Response $response);
 201 }