* There's no more need for this here than anywhere else..

[mediawiki.git] / includes / SpecialExport.php

<?php
# Copyright (C) 2003 Brion Vibber <brion@pobox.com>
# http://www.mediawiki.org/
# 
# 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
/**
 *
 * @package MediaWiki
 * @subpackage SpecialPage
 */

/** */
require_once( 'Revision.php' );

/**
 *
 */
function wfSpecialExport( $page = '' ) {
        global $wgOut, $wgLang, $wgRequest;
        
        if( $wgRequest->getVal( 'action' ) == 'submit') {
                $page = $wgRequest->getText( 'pages' );
                $curonly = $wgRequest->getCheck( 'curonly' );
        } else {
                # Pre-check the 'current version only' box in the UI
                $curonly = true;
        }
        
        if( $page != '' ) {
                $wgOut->disable();
                header( "Content-type: application/xml; charset=utf-8" );
                $pages = explode( "\n", $page );
                
                $db =& wfGetDB( DB_SLAVE );
                $history = $curonly ? MW_EXPORT_CURRENT : MW_EXPORT_FULL;
                $exporter = new WikiExporter( $db, $history );
                $exporter->openStream();
                $exporter->pagesByName( $pages );
                $exporter->closeStream();
                return;
        }
        
        $wgOut->addWikiText( wfMsg( "exporttext" ) );
        $titleObj = Title::makeTitle( NS_SPECIAL, "Export" );
        $action = $titleObj->escapeLocalURL( 'action=submit' );
        $wgOut->addHTML( "
<form method='post' action=\"$action\">
<input type='hidden' name='action' value='submit' />
<textarea name='pages' cols='40' rows='10'></textarea><br />
<label><input type='checkbox' name='curonly' value='true' checked='checked' />
" . wfMsg( "exportcuronly" ) . "</label><br />
<input type='submit' />
</form>
" );
}

define( 'MW_EXPORT_FULL',     0 );
define( 'MW_EXPORT_CURRENT',  1 );

define( 'MW_EXPORT_BUFFER',   0 );
define( 'MW_EXPORT_STREAM',   1 );

/**
 * @package MediaWiki
 * @subpackage SpecialPage
 */
class WikiExporter {
        var $pageCallback = null;
        var $revCallback = null;
        
        /**
         * If using MW_EXPORT_STREAM to stream a large amount of data,
         * provide a database connection which is not managed by
         * LoadBalancer to read from: some history blob types will
         * make additional queries to pull source data while the
         * main query is still running.
         *
         * @param Database $db
         * @param int $history one of MW_EXPORT_FULL or MW_EXPORT_CURRENT
         * @param int $buffer one of MW_EXPORT_BUFFER or MW_EXPORT_STREAM
         */
        function WikiExporter( &$db, $history = MW_EXPORT_CURRENT,
                        $buffer = MW_EXPORT_BUFFER ) {
                $this->db =& $db;
                $this->history = $history;
                $this->buffer  = $buffer;
        }
        
        /**
         * Set a callback to be called after each page in the output
         * stream is closed. The callback will be passed a database row
         * object with the last revision output.
         *
         * A set callback can be removed by passing null here.
         *
         * @param mixed $callback
         */
        function setPageCallback( $callback ) {
                $this->pageCallback = $callback;
        }
        
        /**
         * Set a callback to be called after each revision in the output
         * stream is closed. The callback will be passed a database row
         * object with the revision data.
         *
         * A set callback can be removed by passing null here.
         *
         * @param mixed $callback
         */
        function setRevisionCallback( $callback ) {
                $this->revCallback = $callback;
        }
        
        /**
         * Returns the export schema version.
         * @return string
         */
        function schemaVersion() {
                return "0.3";
        }
        
        /**
         * Opens the XML output stream's root <mediawiki> element.
         * This does not include an xml directive, so is safe to include
         * as a subelement in a larger XML stream. Namespace and XML Schema
         * references are included.
         *
         * To capture the stream to a string, use PHP's output buffering
         * functions. Output will be encoded in UTF-8.
         */
        function openStream() {
                global $wgContLanguageCode;
                $ver = $this->schemaVersion();
                print wfElement( 'mediawiki', array(
                        'xmlns'              => "http://www.mediawiki.org/xml/export-$ver/",
                        'xmlns:xsi'          => "http://www.w3.org/2001/XMLSchema-instance",
                        'xsi:schemaLocation' => "http://www.mediawiki.org/xml/export-$ver/ " .
                                                "http://www.mediawiki.org/xml/export-$ver.xsd",
                        'version'            => $ver,
                        'xml:lang'           => $wgContLanguageCode ),
                        null ) . "\n";
                $this->siteInfo();
        }
        
        function siteInfo() {
                $info = array(
                        $this->sitename(),
                        $this->homelink(),
                        $this->generator(),
                        $this->caseSetting(),
                        $this->namespaces() );
                print "<siteinfo>\n";
                foreach( $info as $item ) {
                        print "  $item\n";
                }
                print "</siteinfo>\n";
        }
        
        function sitename() {
                global $wgSitename;
                return wfElement( 'sitename', array(), $wgSitename );
        }
        
        function generator() {
                global $wgVersion;
                return wfElement( 'generator', array(), "MediaWiki $wgVersion" );
        }
        
        function homelink() {
                $page = Title::newFromText( wfMsgForContent( 'mainpage' ) );
                return wfElement( 'base', array(), $page->getFullUrl() );
        }
        
        function caseSetting() {
                global $wgCapitalLinks;
                // "case-insensitive" option is reserved for future
                $sensitivity = $wgCapitalLinks ? 'first-letter' : 'case-sensitive';
                return wfElement( 'case', array(), $sensitivity );
        }
        
        function namespaces() {
                global $wgContLang;
                $spaces = "<namespaces>\n";
                foreach( $wgContLang->getNamespaces() as $ns => $title ) {
                        $spaces .= '    ' . wfElement( 'namespace',
                                array( 'key' => $ns ),
                                str_replace( '_', ' ', $title ) ) . "\n";
                }
                $spaces .= "  </namespaces>";
                return $spaces;
        }
        
        /**
         * Closes the output stream with the closing root element.
         * Call when finished dumping things.
         */
        function closeStream() {
                print "</mediawiki>\n";
        }
        
        /**
         * Dumps a series of page and revision records for all pages
         * in the database, either including complete history or only
         * the most recent version.
         *
         *
         * @param Database $db
         */
        function allPages() {
                return $this->dumpFrom( '' );
        }
        
        /**
         * @param Title $title
         */
        function pageByTitle( $title ) {
                return $this->dumpFrom(
                        'page_namespace=' . $title->getNamespace() .
                        ' AND page_title=' . $this->db->addQuotes( $title->getDbKey() ) );
        }
        
        function pageByName( $name ) {
                $title = Title::newFromText( $name );
                if( is_null( $title ) ) {
                        return WikiError( "Can't export invalid title" );
                } else {
                        return $this->pageByTitle( $title );
                }
        }
        
        function pagesByName( $names ) {
                foreach( $names as $name ) {
                        $this->pageByName( $name );
                }
        }

        
        // -------------------- private implementation below --------------------
        
        function dumpFrom( $cond = '' ) {
                $fname = 'WikiExporter::dumpFrom';
                wfProfileIn( $fname );
                
                $page     = $this->db->tableName( 'page' );
                $revision = $this->db->tableName( 'revision' );
                $text     = $this->db->tableName( 'text' );
                
                if( $this->history == MW_EXPORT_FULL ) {
                        $join = 'page_id=rev_page';
                } elseif( $this->history == MW_EXPORT_CURRENT ) {
                        $join = 'page_id=rev_page AND page_latest=rev_id';
                } else {
                        wfProfileOut( $fname );
                        return new WikiError( "$fname given invalid history dump type." );
                }
                $where = ( $cond == '' ) ? '' : "$cond AND";
                
                if( $this->buffer == MW_EXPORT_STREAM ) {
                        $prev = $this->db->bufferResults( false );
                }
                $result = $this->db->query(
                        "SELECT * FROM
                                $page FORCE INDEX (PRIMARY),
                                $revision FORCE INDEX(page_timestamp),
                                $text
                                WHERE $where $join AND rev_text_id=old_id
                                ORDER BY page_id", $fname );
                $wrapper = $this->db->resultObject( $result );
                $this->outputStream( $wrapper );
                
                if( $this->buffer == MW_EXPORT_STREAM ) {
                        $this->db->bufferResults( $prev );
                }
                
                wfProfileOut( $fname );
        }
        
        /**
         * Runs through a query result set dumping page and revision records.
         * The result set should be sorted/grouped by page to avoid duplicate
         * page records in the output.
         *
         * The result set will be freed once complete. Should be safe for
         * streaming (non-buffered) queries, as long as it was made on a
         * separate database connection not managed by LoadBalancer; some
         * blob storage types will make queries to pull source data.
         *
         * @param ResultWrapper $resultset
         * @access private
         */
        function outputStream( $resultset ) {
                $last = null;
                while( $row = $resultset->fetchObject() ) {
                        if( is_null( $last ) ||
                                $last->page_namespace != $row->page_namespace ||
                                $last->page_title     != $row->page_title ) {
                                if( isset( $last ) ) {
                                        $this->closePage( $last );
                                }
                                $this->openPage( $row );
                                $last = $row;
                        }
                        $this->dumpRev( $row );
                }
                if( isset( $last ) ) {
                        $this->closePage( $last );
                }
                $resultset->free();
        }
        
        /**
         * Opens a <page> section on the output stream, with data
         * from the given database row.
         *
         * @param object $row
         * @access private
         */
        function openPage( $row ) {
                print "<page>\n";
                $title = Title::makeTitle( $row->page_namespace, $row->page_title );
                print '  ' . wfElementClean( 'title', array(), $title->getPrefixedText() ) . "\n";
                print '  ' . wfElement( 'id', array(), $row->page_id ) . "\n";
                if( '' != $row->page_restrictions ) {
                        print '  ' . wfElement( 'restrictions', array(),
                                $row->page_restrictions ) . "\n";
                }
        }
        
        /**
         * Closes a <page> section on the output stream.
         * If a per-page callback has been set, it will be called
         * and passed the last database row used for this page.
         *
         * @param object $row
         * @access private
         */
        function closePage( $row ) {
                print "</page>\n";
                if( isset( $this->pageCallback ) ) {
                        call_user_func( $this->pageCallback, $row );
                }
        }
        
        /**
         * Dumps a <revision> section on the output stream, with
         * data filled in from the given database row.
         *
         * @param object $row
         * @access private
         */
        function dumpRev( $row ) {
                $fname = 'WikiExporter::dumpRev';
                wfProfileIn( $fname );
                
                print "    <revision>\n";
                print "      " . wfElement( 'id', null, $row->rev_id ) . "\n";
                
                $ts = wfTimestamp2ISO8601( $row->rev_timestamp );
                print "      " . wfElement( 'timestamp', null, $ts ) . "\n";
                
                print "      <contributor>";
                if( $row->rev_user ) {
                        print wfElementClean( 'username', null, $row->rev_user_text );
                        print wfElement( 'id', null, $row->rev_user );
                } else {
                        print wfElementClean( 'ip', null, $row->rev_user_text );
                }
                print "</contributor>\n";
                
                if( $row->rev_minor_edit ) {
                        print  "      <minor/>\n";
                }
                if( $row->rev_comment != '' ) {
                        print "      " . wfElementClean( 'comment', null, $row->rev_comment ) . "\n";
                }
        
                $text = Revision::getRevisionText( $row );
                print "      " . wfElementClean( 'text',
                        array( 'xml:space' => 'preserve' ), $text ) . "\n";
                
                print "    </revision>\n";
                
                wfProfileOut( $fname );
                
                if( isset( $this->revCallback ) ) {
                        call_user_func( $this->revCallback, $row );
                }
        }

}

function wfTimestamp2ISO8601( $ts ) {
        #2003-08-05T18:30:02Z
        return preg_replace( '/^(....)(..)(..)(..)(..)(..)$/', '$1-$2-$3T$4:$5:$6Z', $ts );
}

function xmlsafe( $string ) {
        $fname = 'xmlsafe';
        wfProfileIn( $fname );
        
        /**
         * The page may contain old data which has not been properly normalized.
         * Invalid UTF-8 sequences or forbidden control characters will make our
         * XML output invalid, so be sure to strip them out.
         */
        $string = UtfNormal::cleanUp( $string );
        
        $string = htmlspecialchars( $string );
        wfProfileOut( $fname );
        return $string;
}

?>