Extension:Article Class Extended

<?php
/*
 * ArticleEx.php
 * 
 * MediaWiki extension
 * @author: Jean-Lou Dupont (http://www.bluecortex.com)
 *
 * Purpose:  Extends the MW Article class to handle
 *           the serving of pages without skin and addressed
 *           through explicit type information.
 *           Example:
 *           /index.php?title=Main:somexmldatapage.xml
 *           The actual MW stored article is titled:
 *           "Main:somexmldatapage" and the "raw" form
 *           is addressed with the above URL.
 *
 * Supported types:  all.  Data is retrieved from
 *                   a section delimited with an XML style
 *                   tag.  E.g. for an XSL XML stylesheet,
 *                   the page data would be enclosed in
 *                   <xsl> stylesheet data here </xsl>  
 *
 * Tested Compatibility: MW 1.8.2
 *
 * History:
 * v1.0         Initial availability
 * v1.1         - Added "ArticleViewEx" hook
 * v1.2         - Added "ArticleViewExBegin" hook
 *          - Added a general purpose "attributes" array.
 *          - Added the capability to flag is the said article
 *            is the first loaded in a transaction.
 * v1.3         - Corrected major bug: if article did not exists
 *                        would cause a fatal error.
 * v1.4         - Corrected maor bug: if an non-existing page from
 *            the following namespaces is requested (NS_MEDIA,
 *            NS_CATEGORY, NS_IMAGE), the standard processing
 *            flow should have been continued.
 * v1.5     - Corrected bug: initialised attributes array AFTER
 *            setting some variables causing loss of variables...
 * v1.6     - Added support for retrieving the 'categorylinks'
 *            when a valid article is loaded. The data can be found
 *            in '$this->categories'.
 *            This functionality is especially useful when templates
 *            require 'categorisation' level information.
 *          - Added initialisation of the global variable 'wgArticle'.
 *            Normally, this global variable is initialised a little bit
 *            too late to be useful i.e. after the action on the page is
 *            actually performed (see Wiki.php 'initialize' function).
 *
 * v1.7     - (a) Added chaining capability to 'ArticleViewExBegin' hook.
 *
 */
$wgExtensionCredits['other'][] = array( 
        'name'    => 'ArticleEx',
        'version' => '1.7',
        'author'  => 'Jean-Lou Dupont', 
        'url'     => 'http://www.bluecortex.com',
);
 
require_once(dirname( __FILE__ ) . '/ArticleExClass.php');
 
$wgExtensionFunctions[] = "wfArticleExSetup";
 
function wfArticleExSetup()
{
        global $wgHooks;
        $wgHooks['ArticleFromTitle'][] = 'wfArticleExInit';      
}
 
function wfArticleExInit( &$title, &$article )
{
        // What really counts is what is returned in $article.
        $GLOBALS['wgArticle'] = new ArticleExClass( $title, $article, true );
        return true;  
} 
?>
</pre>
 
<pre>
<?php
/*
 * ArticleExClass.php
 * 
 * MediaWiki extension
 * @author: Jean-Lou Dupont (http://www.bluecortex.com)
*/
 
require_once("$IP/includes/Article.php");
 
class ArticleExClass extends Article
{
        static $qType = array(
                                                        'js'  => array( 'js', 'javascript' ),
                                                        'xsl' => array( 'xsl', 'xml' ),
                                                        'xml' => array( 'xml', 'xsl' ),
                                                );
        var $noskin;
        var $extractSection;
        var $type;
        var $bname;
        var $fname;
        var $section;
        var $attributes;
        var $foundDot;
 
        public function ArticleExClass( &$title, &$article, $firstArticleInTransation=false )
        {
                $this->init();   
                $this->setA("first", $firstArticleInTransation );  // new in v1.2
                $this->create( $title, $article );
        }
 
        public function init()
        {
                $this->noskin = false;
                $this->type   = null;
                $this->bname  = "";
                $this->extractSection = false;
                $this->section = null;
                $this->attributes = array();
                $this->foundDot = false;
        }
 
        // Attributes table 'getter/setter' interface.
        // v1.2 change.
        public function setA($key,$value) { $this->attributes[$key]=$value; }
        public function getA($key)           { return @$this->attributes[$key]; }
 
        public function create( &$title, &$article )
        /*
         *   Hook function handler.
         *   Substitutes an ArticleEx object instance in place
         *   of the usual MW Article class object.
         *
         */
        {
                // Check the special cases
                $ns = $title->getNamespace();
                if ($ns == NS_MEDIA || $ns == NS_IMAGE || $ns == NS_CATEGORY)
                        return null; // let the normal flow proceed.
 
                parent::__construct( $title );
                $article = $this;
 
                // Let's check the database if a page matching the title name
                // actually exists... if one does, then abort our special hook.
                if ($this->getID()!=0)
                        return true;  // continue the hook chain.
 
                // First, extract base name from MW Title Class object.
                // The base name takes the form:
                //    somemwprefixeddbkey.type
                // Where only the right most '.' delimits the 'type' information
                $n = $this->fname = $this->getTitle()->getPrefixedDBkey();
                $p = strrpos( $n, "." );
 
                if ($p===false)    // no '.' found, bail out.
                        return true;
 
                // Raise a flag to simplify our lives in the view() method.
                $this->foundDot = true;
 
                // We are anyhow dealing with a valid MW title name,
                // so spare the security checks.
                $this->bname = substr($n, 0, $p);
                $this->type  = substr($n, $p+1 );
 
                return true; // continue the hook chain.
        }
 
        public function view()
        {
                // V1.2 change
                // Don't forget to check user rights (if applicable) 
                // in the extensions that attach here!
                if (!wfRunHooks( 'ArticleViewExBegin', array( &$this ) ))
                        return; // v1.7 feature (a)
 
                if (!$this->foundDot)
                        return parent::view();                              
 
                // if the article does not exists (probably given the 'type' extension
                // appended to the title name) & an actual 'type' extension is 
                // found in the title name, then let's check if an article actually
                // exists with a title name that EXCLUDES the 'type' extension.
                if ($this->getID()!=0)
                        return parent::view();
 
                // at this point, we know that the article does not exist.
                // Let's check for an article with for title one without
                // the 'type' extension.
                $title = Title::newFromText($this->bname);
                $this->mTitle = $title; 
                $this->clear();
                $this->oldid= null;
 
                // nope...
                if ($this->getID()==0)
                {
                        // good thing we kept the full title name just in case!
                        $title = Title::newFromText($this->fname);
                        $this->mTitle = $title;
                        $this->clear();
                        $this->oldid = null;
                        return parent::view(); // go with default behavior
                }
 
                // At this point, we know we have a valid article
 
                // Check User Rights...
                if (!$title->userCanRead()) 
                        return parent::view(); // let the normal flow handle this one...
 
                $this->loadContent();
 
                $this->extractSection = empty($this->type) ? false:true;    
 
                #echo "type = $this->type, extract= $this->extractSection <br/>";
 
                if ($this->extractSection)
                        $this->section = $this->extractSection( $this->type, $this->mContent ) ;                     
 
                #echo $this->section;
 
                // DEFAULT BEHAVIOR:
                // If we have detected a "type" in the page name,
                // then serve the page without the skin.
                $this->noskin = empty($this->type) ? false:true;
                $content = $this->section;
 
                // The other parameters can be fetched from the object itself.
                // Parameters passed:
                // - ArticleEx object instance
                // - type e.g. xml, xsl etc.
                // - content  (what is about to be returned if nothing is done)
                // 
                // NOTE: at this point, the variable $content does not include the
                //       Mediawiki content enclosing tags e.g. <xml> content </xml>
                wfRunHooks( 'ArticleViewEx', array( &$this, &$this->type, &$content ) );
 
                global $wgOut;
                $wgOut->clearHTML();
                $wgOut->addHTML( $content );                            
 
                // next, let's see if we need to apply special treatment.
                if ($this->noskin)
                        $wgOut->setArticleBodyOnly(true);
 
        }
        private function extractSection( &$type, &$content )
        {
                // check if we have multiple choices
                if (isset(self::$qType[$type]))
                {
                        $tags = self::$qType[$type];
                        foreach( $tags as $tag )
                        {
                                $pattern = "/<".$tag."(?:.*)\>(.*)(?:\<</span>.?".$tag.">)/siU";
                                $r = preg_match_all( $pattern, $content, $m );
                                if ($r>0)
                                        break;
                        }
                }
                else
                {
                        $pattern = "/<".$type."(?:.*)\>(.*)(?:\<</span>.?".$type.">)/siU";
                        preg_match_all( $pattern, $content, $m );
                }
 
                return trim( $m[1][0] ); // just the first submatch
        }
 
// =================================================================================
 
        public function loadPageData( $data = 'fromdb' )
        /*
         *   This hook is used to retrieve all the categories associated with an article.
         */
        {
                $ret = parent::loadPageData( $data ); // get return code just in case.
 
                // At this point, we have a valid 'page id' in a local variable.
                // Use it to query the database for 'categorylinks'
                $dbr      =& wfGetDB( DB_SLAVE );
                $page     = $dbr->tableName( 'page' );
        $catlinks = $dbr->tableName( 'categorylinks' ); 
 
                $id = $this->getID();
 
                $query = "SELECT cl_to FROM {$catlinks} WHERE {$catlinks}.cl_from={$id}";
 
                $results = $dbr->query( $query );
                $count   = $dbr->numRows( $results );
 
                if ($count>=1)
                        while( $row = $dbr->fetchObject( $results ) )
                                $this->categories[] = $row->cl_to;
 
                $dbr->freeResult( $results );
 
                return $ret;
        }
 
} // End class definition.
?>