includes/api/ApiMain.php

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