includes/api/ApiMain.php

   1 <?php
   2
   3
   4 /*
   5  * Created on Sep 4, 2006
   6  *
   7  * API for MediaWiki 1.8+
   8  *
   9  * Copyright (C) 2006 Yuri Astrakhan <FirstnameLastname@gmail.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License along
  22  * with this program; if not, write to the Free Software Foundation, Inc.,
  23  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24  * http://www.gnu.org/copyleft/gpl.html
  25  */
  26
  27 if (!defined('MEDIAWIKI')) {
  28         // Eclipse helper - will be ignored in production
  29         require_once ('ApiBase.php');
  30 }
  31
  32 /**
  33  * This is the main API class, used for both external and internal processing.
  34  */
  35 class ApiMain extends ApiBase {
  36
  37         /**
  38          * When no format parameter is given, this format will be used
  39          */
  40         const API_DEFAULT_FORMAT = 'xmlfm';
  41
  42         /**
  43          * List of available modules: action name => module class
  44          */
  45         private static $Modules = array (
  46                 'help' => 'ApiHelp',
  47                 'login' => 'ApiLogin',
  48                 'opensearch' => 'ApiOpenSearch',
  49                 'feedwatchlist' => 'ApiFeedWatchlist',
  50                 'query' => 'ApiQuery'
  51         );
  52
  53         /**
  54          * List of available formats: format name => format class
  55          */
  56         private static $Formats = array (
  57                 'json' => 'ApiFormatJson',
  58                 'jsonfm' => 'ApiFormatJson',
  59                 'php' => 'ApiFormatPhp',
  60                 'phpfm' => 'ApiFormatPhp',
  61                 'wddx' => 'ApiFormatWddx',
  62                 'wddxfm' => 'ApiFormatWddx',
  63                 'xml' => 'ApiFormatXml',
  64                 'xmlfm' => 'ApiFormatXml',
  65                 'yaml' => 'ApiFormatYaml',
  66                 'yamlfm' => 'ApiFormatYaml',
  67                 'raw' => 'ApiFormatJson',
  68                 'rawfm' => 'ApiFormatJson'
  69         );
  70
  71         private $mPrinter, $mModules, $mModuleNames, $mFormats, $mFormatNames;
  72         private $mResult, $mShowVersions, $mEnableWrite, $mRequest, $mInternalMode, $mSquidMaxage;
  73
  74         /**
  75         * Constructor
  76         * @param $request object - if this is an instance of FauxRequest, errors are thrown and no printing occurs
  77         * @param $enableWrite bool should be set to true if the api may modify data
  78         */
  79         public function __construct($request, $enableWrite = false) {
  80
  81                 $this->mInternalMode = ($request instanceof FauxRequest);
  82
  83                 // Special handling for the main module: $parent === $this
  84                 parent :: __construct($this, $this->mInternalMode ? 'main_int' : 'main');
  85
  86                 $this->mModules = self :: $Modules;
  87                 $this->mModuleNames = array_keys($this->mModules); // todo: optimize
  88                 $this->mFormats = self :: $Formats;
  89                 $this->mFormatNames = array_keys($this->mFormats); // todo: optimize
  90
  91                 $this->mResult = new ApiResult($this);
  92                 $this->mShowVersions = false;
  93                 $this->mEnableWrite = $enableWrite;
  94
  95                 $this->mRequest = & $request;
  96
  97                 $this->mSquidMaxage = 0;
  98         }
  99
 100         public function & getRequest() {
 101                 return $this->mRequest;
 102         }
 103
 104         public function & getResult() {
 105                 return $this->mResult;
 106         }
 107
 108         public function requestWriteMode() {
 109                 if (!$this->mEnableWrite)
 110                         $this->dieUsage('Editing of this site is disabled. Make sure the $wgEnableWriteAPI=true; ' .
 111                         'statement is included in the site\'s LocalSettings.php file', 'readonly');
 112         }
 113
 114         public function setCacheMaxAge($maxage) {
 115                 $this->mSquidMaxage = $maxage;
 116         }
 117
 118         public function createPrinterByName($format) {
 119                 return new $this->mFormats[$format] ($this, $format);
 120         }
 121
 122         public function execute() {
 123                 $this->profileIn();
 124                 if ($this->mInternalMode)
 125                         $this->executeAction();
 126                 else
 127                         $this->executeActionWithErrorHandling();
 128                 $this->profileOut();
 129         }
 130
 131         protected function executeActionWithErrorHandling() {
 132
 133                 // In case an error occurs during data output,
 134                 // this clear the output buffer and print just the error information
 135                 ob_start();
 136
 137                 try {
 138                         $this->executeAction();
 139                 } catch (Exception $e) {
 140                         //
 141                         // Handle any kind of exception by outputing properly formatted error message.
 142                         // If this fails, an unhandled exception should be thrown so that global error
 143                         // handler will process and log it.
 144                         //
 145
 146                         // Error results should not be cached
 147                         $this->setCacheMaxAge(0);
 148
 149                         // Printer may not be initialized if the extractRequestParams() fails for the main module
 150                         if (!isset ($this->mPrinter)) {
 151                                 $this->mPrinter = $this->createPrinterByName(self :: API_DEFAULT_FORMAT);
 152                                 if ($this->mPrinter->getNeedsRawData())
 153                                         $this->getResult()->setRawMode();
 154                         }
 155
 156                         if ($e instanceof UsageException) {
 157                                 //
 158                                 // User entered incorrect parameters - print usage screen
 159                                 //
 160                                 $errMessage = array (
 161                                 'code' => $e->getCodeString(), 'info' => $e->getMessage());
 162                                 ApiResult :: setContent($errMessage, $this->makeHelpMsg());
 163
 164                         } else {
 165                                 //
 166                                 // Something is seriously wrong
 167                                 //
 168                                 $errMessage = array (
 169                                         'code' => 'internal_api_error',
 170                                         'info' => "Exception Caught: {$e->getMessage()}"
 171                                 );
 172                                 ApiResult :: setContent($errMessage, "\n\n{$e->getTraceAsString()}\n\n");
 173                         }
 174
 175                         $headerStr = 'MediaWiki-API-Error: ' . $errMessage['code'];
 176                         if ($e->getCode() === 0)
 177                                 header($headerStr, true);
 178                         else
 179                                 header($headerStr, true, $e->getCode());
 180
 181                         // Reset and print just the error message
 182                         ob_clean();
 183                         $this->getResult()->reset();
 184                         $this->getResult()->addValue(null, 'error', $errMessage);
 185
 186                         // If the error occured during printing, do a printer->profileOut()
 187                         $this->mPrinter->safeProfileOut();
 188                         $this->printResult(true);
 189                 }
 190
 191                 // Set the cache expiration at the last moment, as any errors may change the expiration.
 192                 // if $this->mSquidMaxage == 0, the expiry time is set to the first second of unix epoch
 193                 $expires = $this->mSquidMaxage == 0 ? 1 : time() + $this->mSquidMaxage;
 194                 header('Expires: ' . wfTimestamp(TS_RFC2822, $expires));
 195                 header('Cache-Control: s-maxage=' . $this->mSquidMaxage . ', must-revalidate, max-age=0');
 196
 197                 ob_end_flush();
 198         }
 199
 200         /**
 201          * Execute the actual module, without any error handling
 202          */
 203         protected function executeAction() {
 204                 $action = $format = $version = null;
 205                 extract($this->extractRequestParams());
 206                 $this->mShowVersions = $version;
 207
 208                 // Instantiate the module requested by the user
 209                 $module = new $this->mModules[$action] ($this, $action);
 210
 211                 if (!$this->mInternalMode) {
 212
 213                         // See if custom printer is used
 214                         $this->mPrinter = $module->getCustomPrinter();
 215                         if (is_null($this->mPrinter)) {
 216                                 // Create an appropriate printer
 217                                 $this->mPrinter = $this->createPrinterByName($format);
 218                         }
 219
 220                         if ($this->mPrinter->getNeedsRawData())
 221                                 $this->getResult()->setRawMode();
 222                 }
 223
 224                 // Execute
 225                 $module->profileIn();
 226                 $module->execute();
 227                 $module->profileOut();
 228
 229                 if (!$this->mInternalMode) {
 230                         // Print result data
 231                         $this->printResult(false);
 232                 }
 233         }
 234
 235         /**
 236          * Internal printer
 237          */
 238         protected function printResult($isError) {
 239                 $printer = $this->mPrinter;
 240                 $printer->profileIn();
 241                 $printer->initPrinter($isError);
 242                 $printer->execute();
 243                 $printer->closePrinter();
 244                 $printer->profileOut();
 245         }
 246
 247         protected function getAllowedParams() {
 248                 return array (
 249                         'format' => array (
 250                                 ApiBase :: PARAM_DFLT => ApiMain :: API_DEFAULT_FORMAT,
 251                                 ApiBase :: PARAM_TYPE => $this->mFormatNames
 252                         ),
 253                         'action' => array (
 254                                 ApiBase :: PARAM_DFLT => 'help',
 255                                 ApiBase :: PARAM_TYPE => $this->mModuleNames
 256                         ),
 257                         'version' => false
 258                 );
 259         }
 260
 261         protected function getParamDescription() {
 262                 return array (
 263                         'format' => 'The format of the output',
 264                         'action' => 'What action you would like to perform',
 265                         'version' => 'When showing help, include version for each module'
 266                 );
 267         }
 268
 269         protected function getDescription() {
 270                 return array (
 271                         '',
 272                         'This API allows programs to access various functions of MediaWiki software.',
 273                         'For more details see API Home Page @ http://meta.wikimedia.org/wiki/API',
 274                         '',
 275                         'Status: ALPHA -- all features shown on this page should be working,',
 276                         '                 but the API is still in active development, and  may change at any time.',
 277                         '                 Make sure you monitor changes to this page, wikitech-l mailing list,',
 278                         '                 or the source code in the includes/api directory for any changes.',
 279                         ''
 280                 );
 281         }
 282
 283         protected function getCredits() {
 284                 return array(
 285                         'This API is being implemented by Yuri Astrakhan [[User:Yurik]] / FirstnameLastname@gmail.com',
 286                         'Please leave your comments and suggestions at http://meta.wikimedia.org/wiki/API'
 287                 );
 288         }
 289
 290         /**
 291          * Override the parent to generate help messages for all available modules.
 292          */
 293         public function makeHelpMsg() {
 294
 295                 // Use parent to make default message for the main module
 296                 $msg = parent :: makeHelpMsg();
 297
 298                 $astriks = str_repeat('*** ', 10);
 299                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
 300                 foreach ($this->mModules as $moduleName => $moduleClass) {
 301                         $msg .= "* action=$moduleName *";
 302                         $module = new $this->mModules[$moduleName] ($this, $moduleName);
 303                         $msg2 = $module->makeHelpMsg();
 304                         if ($msg2 !== false)
 305                                 $msg .= $msg2;
 306                         $msg .= "\n";
 307                 }
 308
 309                 $msg .= "\n$astriks Formats  $astriks\n\n";
 310                 foreach ($this->mFormats as $formatName => $moduleClass) {
 311                         $msg .= "* format=$formatName *";
 312                         $module = $this->createPrinterByName($formatName);
 313                         $msg2 = $module->makeHelpMsg();
 314                         if ($msg2 !== false)
 315                                 $msg .= $msg2;
 316                         $msg .= "\n";
 317                 }
 318
 319                 $msg .= "\n*** Credits: ***\n   " . implode("\n   ", $this->getCredits()) . "\n";
 320
 321
 322                 return $msg;
 323         }
 324
 325         private $mIsBot = null;
 326         public function isBot() {
 327                 if (!isset ($this->mIsBot)) {
 328                         global $wgUser;
 329                         $this->mIsBot = $wgUser->isAllowed('bot');
 330                 }
 331                 return $this->mIsBot;
 332         }
 333
 334         public function getShowVersions() {
 335                 return $this->mShowVersions;
 336         }
 337
 338         public function getVersion() {
 339                 $vers = array ();
 340                 $vers[] = __CLASS__ . ': $Id$';
 341                 $vers[] = ApiBase :: getBaseVersion();
 342                 $vers[] = ApiFormatBase :: getBaseVersion();
 343                 $vers[] = ApiQueryBase :: getBaseVersion();
 344                 $vers[] = ApiFormatFeedWrapper :: getVersion(); // not accessible with format=xxx
 345                 return $vers;
 346         }
 347 }
 348
 349 /**
 350 * @desc This exception will be thrown when dieUsage is called to stop module execution.
 351 */
 352 class UsageException extends Exception {
 353
 354         private $mCodestr;
 355
 356         public function __construct($message, $codestr, $code = 0) {
 357                 parent :: __construct($message, $code);
 358                 $this->mCodestr = $codestr;
 359         }
 360         public function getCodeString() {
 361                 return $this->mCodestr;
 362         }
 363         public function __toString() {
 364                 return "{$this->getCodeString()}: {$this->getMessage()}";
 365         }
 366 }
 367 ?>