* Use ui language now that it is possible

[mediawiki.git] / includes / api / ApiMain.php

<?php


/*
 * Created on Sep 4, 2006
 *
 * API for MediaWiki 1.8+
 *
 * Copyright (C) 2006 Yuri Astrakhan <FirstnameLastname@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 * http://www.gnu.org/copyleft/gpl.html
 */

if (!defined('MEDIAWIKI')) {
        // Eclipse helper - will be ignored in production
        require_once ('ApiBase.php');
}

/**
 * This is the main API class, used for both external and internal processing. 
 */
class ApiMain extends ApiBase {

        /**
         * When no format parameter is given, this format will be used
         */
        const API_DEFAULT_FORMAT = 'xmlfm';

        /**
         * List of available modules: action name => module class
         */
        private static $Modules = array (
                'help' => 'ApiHelp',
                'login' => 'ApiLogin',
                'opensearch' => 'ApiOpenSearch',
                'feedwatchlist' => 'ApiFeedWatchlist',
                'query' => 'ApiQuery'
        );

        /**
         * List of available formats: format name => format class
         */
        private static $Formats = array (
                'json' => 'ApiFormatJson',
                'jsonfm' => 'ApiFormatJson',
                'php' => 'ApiFormatPhp',
                'phpfm' => 'ApiFormatPhp',
                'wddx' => 'ApiFormatWddx',
                'wddxfm' => 'ApiFormatWddx',
                'xml' => 'ApiFormatXml',
                'xmlfm' => 'ApiFormatXml',
                'yaml' => 'ApiFormatYaml',
                'yamlfm' => 'ApiFormatYaml',
                'rawfm' => 'ApiFormatJson'
        );

        private $mPrinter, $mModules, $mModuleNames, $mFormats, $mFormatNames;
        private $mResult, $mShowVersions, $mEnableWrite, $mRequest, $mInternalMode, $mSquidMaxage;

        /**
        * Constructor
        * @param $request object - if this is an instance of FauxRequest, errors are thrown and no printing occurs
        * @param $enableWrite bool should be set to true if the api may modify data
        */
        public function __construct($request, $enableWrite = false) {

                $this->mInternalMode = ($request instanceof FauxRequest);

                // Special handling for the main module: $parent === $this
                parent :: __construct($this, $this->mInternalMode ? 'main_int' : 'main');

                $this->mModules = self :: $Modules;
                $this->mModuleNames = array_keys($this->mModules); // todo: optimize
                $this->mFormats = self :: $Formats;
                $this->mFormatNames = array_keys($this->mFormats); // todo: optimize

                $this->mResult = new ApiResult($this);
                $this->mShowVersions = false;
                $this->mEnableWrite = $enableWrite;

                $this->mRequest = & $request;

                $this->mSquidMaxage = 0;
        }

        public function & getRequest() {
                return $this->mRequest;
        }

        public function getResult() {
                return $this->mResult;
        }

        public function requestWriteMode() {
                if (!$this->mEnableWrite)
                        $this->dieUsage('Editing of this site is disabled. Make sure the $wgEnableWriteAPI=true; ' .
                        'statement is included in the site\'s LocalSettings.php file', 'readonly');
        }

        public function setCacheMaxAge($maxage) {
                $this->mSquidMaxage = $maxage;
        }

        public function createPrinterByName($format) {
                return new $this->mFormats[$format] ($this, $format);
        }

        public function execute() {
                $this->profileIn();
                if ($this->mInternalMode)
                        $this->executeAction();
                else
                        $this->executeActionWithErrorHandling();
                $this->profileOut();
        }

        protected function executeActionWithErrorHandling() {

                // In case an error occurs during data output,
                // this clear the output buffer and print just the error information
                ob_start();

                try {
                        $this->executeAction();
                } catch (Exception $e) {
                        //
                        // Handle any kind of exception by outputing properly formatted error message.
                        // If this fails, an unhandled exception should be thrown so that global error
                        // handler will process and log it.
                        //

                        // Error results should not be cached
                        $this->setCacheMaxAge(0);

                        // Printer may not be initialized if the extractRequestParams() fails for the main module
                        if (!isset ($this->mPrinter)) {
                                $this->mPrinter = $this->createPrinterByName(self :: API_DEFAULT_FORMAT);
                                if ($this->mPrinter->getNeedsRawData())
                                        $this->getResult()->setRawMode();
                        }

                        if ($e instanceof UsageException) {
                                //
                                // User entered incorrect parameters - print usage screen
                                //
                                $errMessage = array (
                                'code' => $e->getCodeString(), 'info' => $e->getMessage());
                                ApiResult :: setContent($errMessage, $this->makeHelpMsg());

                        } else {
                                //
                                // Something is seriously wrong
                                //
                                $errMessage = array (
                                        'code' => 'internal_api_error',
                                        'info' => "Exception Caught: {$e->getMessage()}"
                                );
                                ApiResult :: setContent($errMessage, "\n\n{$e->getTraceAsString()}\n\n");
                        }

                        $headerStr = 'MediaWiki-API-Error: ' . $errMessage['code'];
                        if ($e->getCode() === 0)
                                header($headerStr, true);
                        else
                                header($headerStr, true, $e->getCode());

                        // Reset and print just the error message
                        ob_clean();
                        $this->getResult()->reset();
                        $this->getResult()->addValue(null, 'error', $errMessage);

                        // If the error occured during printing, do a printer->profileOut()
                        $this->mPrinter->safeProfileOut();
                        $this->printResult(true);
                }

                // Set the cache expiration at the last moment, as any errors may change the expiration.
                // if $this->mSquidMaxage == 0, the expiry time is set to the first second of unix epoch
                $expires = $this->mSquidMaxage == 0 ? 1 : time() + $this->mSquidMaxage;
                header('Expires: ' . wfTimestamp(TS_RFC2822, $expires));
                header('Cache-Control: s-maxage=' . $this->mSquidMaxage . ', must-revalidate, max-age=0');

                ob_end_flush();
        }

        /**
         * Execute the actual module, without any error handling
         */
        protected function executeAction() {
                $action = $format = $version = null;
                extract($this->extractRequestParams());
                $this->mShowVersions = $version;

                // Instantiate the module requested by the user
                $module = new $this->mModules[$action] ($this, $action);

                if (!$this->mInternalMode) {

                        // See if custom printer is used
                        $this->mPrinter = $module->getCustomPrinter();
                        if (is_null($this->mPrinter)) {
                                // Create an appropriate printer
                                $this->mPrinter = $this->createPrinterByName($format);
                        }

                        if ($this->mPrinter->getNeedsRawData())
                                $this->getResult()->setRawMode();
                }

                // Execute
                $module->profileIn();
                $module->execute();
                $module->profileOut();

                if (!$this->mInternalMode) {
                        // Print result data
                        $this->printResult(false);
                }
        }

        /**
         * Internal printer
         */
        protected function printResult($isError) {
                $printer = $this->mPrinter;
                $printer->profileIn();
                $printer->initPrinter($isError);
                $printer->execute();
                $printer->closePrinter();
                $printer->profileOut();
        }

        protected function getAllowedParams() {
                return array (
                        'format' => array (
                                ApiBase :: PARAM_DFLT => ApiMain :: API_DEFAULT_FORMAT,
                                ApiBase :: PARAM_TYPE => $this->mFormatNames
                        ),
                        'action' => array (
                                ApiBase :: PARAM_DFLT => 'help',
                                ApiBase :: PARAM_TYPE => $this->mModuleNames
                        ),
                        'version' => false
                );
        }

        protected function getParamDescription() {
                return array (
                        'format' => 'The format of the output',
                        'action' => 'What action you would like to perform',
                        'version' => 'When showing help, include version for each module'
                );
        }

        protected function getDescription() {
                return array (
                        '',
                        'This API allows programs to access various functions of MediaWiki software.',
                        'For more details see API Home Page @ http://meta.wikimedia.org/wiki/API',
                        '',
                        'Status: ALPHA -- all features shown on this page should be working,',
                        '                 but the API is still in active development, and  may change at any time.',
                        '                 Make sure you monitor changes to this page, wikitech-l mailing list,',
                        '                 or the source code in the includes/api directory for any changes.',
                        ''
                );
        }
        
        protected function getCredits() {
                return array(
                        'This API is being implemented by Yuri Astrakhan [[User:Yurik]] / FirstnameLastname@gmail.com',
                        'Please leave your comments and suggestions at http://meta.wikimedia.org/wiki/API'
                );
        }

        /**
         * Override the parent to generate help messages for all available modules.
         */
        public function makeHelpMsg() {

                // Use parent to make default message for the main module
                $msg = parent :: makeHelpMsg();

                $astriks = str_repeat('*** ', 10);
                $msg .= "\n\n$astriks Modules  $astriks\n\n";
                foreach( $this->mModules as $moduleName => $unused ) {
                        $msg .= "* action=$moduleName *";
                        $module = new $this->mModules[$moduleName] ($this, $moduleName);
                        $msg2 = $module->makeHelpMsg();
                        if ($msg2 !== false)
                                $msg .= $msg2;
                        $msg .= "\n";
                }

                $msg .= "\n$astriks Formats  $astriks\n\n";
                foreach( $this->mFormats as $formatName => $unused ) {
                        $msg .= "* format=$formatName *";
                        $module = $this->createPrinterByName($formatName);
                        $msg2 = $module->makeHelpMsg();
                        if ($msg2 !== false)
                                $msg .= $msg2;
                        $msg .= "\n";
                }
                
                $msg .= "\n*** Credits: ***\n   " . implode("\n   ", $this->getCredits()) . "\n";
                

                return $msg;
        }

        private $mIsBot = null;
        public function isBot() {
                if (!isset ($this->mIsBot)) {
                        global $wgUser;
                        $this->mIsBot = $wgUser->isAllowed('bot');
                }
                return $this->mIsBot;
        }

        public function getShowVersions() {
                return $this->mShowVersions;
        }

        public function getVersion() {
                $vers = array ();
                $vers[] = __CLASS__ . ': $Id$';
                $vers[] = ApiBase :: getBaseVersion();
                $vers[] = ApiFormatBase :: getBaseVersion();
                $vers[] = ApiQueryBase :: getBaseVersion();
                $vers[] = ApiFormatFeedWrapper :: getVersion(); // not accessible with format=xxx
                return $vers;
        }
}

/**
* @desc This exception will be thrown when dieUsage is called to stop module execution.
*/
class UsageException extends Exception {

        private $mCodestr;

        public function __construct($message, $codestr, $code = 0) {
                parent :: __construct($message, $code);
                $this->mCodestr = $codestr;
        }
        public function getCodeString() {
                return $this->mCodestr;
        }
        public function __toString() {
                return "{$this->getCodeString()}: {$this->getMessage()}";
        }
}
?>