includes/AjaxDispatcher.php

   1 <?php
   2 /**
   3  * Handle ajax requests and send them to the proper handler.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Ajax
  22  */
  23
  24 use MediaWiki\MediaWikiServices;
  25
  26 /**
  27  * @defgroup Ajax Ajax
  28  */
  29
  30 /**
  31  * Object-Oriented Ajax functions.
  32  * @ingroup Ajax
  33  */
  34 class AjaxDispatcher {
  35         /**
  36          * The way the request was made, either a 'get' or a 'post'
  37          * @var string $mode
  38          */
  39         private $mode;
  40
  41         /**
  42          * Name of the requested handler
  43          * @var string $func_name
  44          */
  45         private $func_name;
  46
  47         /** Arguments passed
  48          * @var array $args
  49          */
  50         private $args;
  51
  52         /**
  53          * @var Config
  54          */
  55         private $config;
  56
  57         /**
  58          * Load up our object with user supplied data
  59          */
  60         function __construct( Config $config ) {
  61                 $this->config = $config;
  62
  63                 $this->mode = "";
  64
  65                 if ( !empty( $_GET["rs"] ) ) {
  66                         $this->mode = "get";
  67                 }
  68
  69                 if ( !empty( $_POST["rs"] ) ) {
  70                         $this->mode = "post";
  71                 }
  72
  73                 switch ( $this->mode ) {
  74                         case 'get':
  75                                 $this->func_name = isset( $_GET["rs"] ) ? $_GET["rs"] : '';
  76                                 if ( !empty( $_GET["rsargs"] ) ) {
  77                                         $this->args = $_GET["rsargs"];
  78                                 } else {
  79                                         $this->args = [];
  80                                 }
  81                                 break;
  82                         case 'post':
  83                                 $this->func_name = isset( $_POST["rs"] ) ? $_POST["rs"] : '';
  84                                 if ( !empty( $_POST["rsargs"] ) ) {
  85                                         $this->args = $_POST["rsargs"];
  86                                 } else {
  87                                         $this->args = [];
  88                                 }
  89                                 break;
  90                         default:
  91                                 return;
  92                                 # Or we could throw an exception:
  93                                 # throw new MWException( __METHOD__ . ' called without any data (mode empty).' );
  94                 }
  95         }
  96
  97         /**
  98          * Pass the request to our internal function.
  99          * BEWARE! Data are passed as they have been supplied by the user,
 100          * they should be carefully handled in the function processing the
 101          * request.
 102          *
 103          * @param User $user
 104          */
 105         function performAction( User $user ) {
 106                 if ( empty( $this->mode ) ) {
 107                         return;
 108                 }
 109
 110                 if ( !in_array( $this->func_name, $this->config->get( 'AjaxExportList' ) ) ) {
 111                         wfDebug( __METHOD__ . ' Bad Request for unknown function ' . $this->func_name . "\n" );
 112                         wfHttpError(
 113                                 400,
 114                                 'Bad Request',
 115                                 "unknown function " . $this->func_name
 116                         );
 117                 } elseif ( !User::isEveryoneAllowed( 'read' ) && !$user->isAllowed( 'read' ) ) {
 118                         wfHttpError(
 119                                 403,
 120                                 'Forbidden',
 121                                 'You are not allowed to view pages.' );
 122                 } else {
 123                         wfDebug( __METHOD__ . ' dispatching ' . $this->func_name . "\n" );
 124                         try {
 125                                 $result = call_user_func_array( $this->func_name, $this->args );
 126
 127                                 if ( $result === false || $result === null ) {
 128                                         wfDebug( __METHOD__ . ' ERROR while dispatching ' .
 129                                                 $this->func_name . "(" . var_export( $this->args, true ) . "): " .
 130                                                 "no data returned\n" );
 131
 132                                         wfHttpError( 500, 'Internal Error',
 133                                                 "{$this->func_name} returned no data" );
 134                                 } else {
 135                                         if ( is_string( $result ) ) {
 136                                                 $result = new AjaxResponse( $result );
 137                                         }
 138
 139                                         // Make sure DB commit succeeds before sending a response
 140                                         $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
 141                                         $lbFactory->commitMasterChanges( __METHOD__ );
 142
 143                                         $result->sendHeaders();
 144                                         $result->printText();
 145
 146                                         wfDebug( __METHOD__ . ' dispatch complete for ' . $this->func_name . "\n" );
 147                                 }
 148                         } catch ( Exception $e ) {
 149                                 wfDebug( __METHOD__ . ' ERROR while dispatching ' .
 150                                         $this->func_name . "(" . var_export( $this->args, true ) . "): " .
 151                                         get_class( $e ) . ": " . $e->getMessage() . "\n" );
 152
 153                                 if ( !headers_sent() ) {
 154                                         wfHttpError( 500, 'Internal Error',
 155                                                 $e->getMessage() );
 156                                 } else {
 157                                         print $e->getMessage();
 158                                 }
 159                         }
 160                 }
 161         }
 162 }