coding style tweaks, doc updates, marked some public functions as such
[lhc/web/wiklou.git] / includes / Interwiki.php
index 417159e..036cbe3 100644 (file)
-<?
-# Note -- this file is generated by maintenance/fetchInterwiki.pl
-# Edit and rerun that script rather than modifying this directly.
+<?php
+/**
+ * @file
+ * Interwiki table entry
+ */
 
-/* private */ $wgValidInterwikis = array(
-       # General interwiki links from the InterMap
-       "AbbeNormal" => "http://www.ourpla.net/cgi-bin/pikie.cgi?$1",
-       "AcadWiki" => "http://xarch.tu-graz.ac.at/autocad/wiki/$1",
-       "Acronym" => "http://www.acronymfinder.com/af-query.asp?String=exact&Acronym=$1",
-       "Advogato" => "http://www.advogato.org/$1",
-       "AIWiki" => "http://www.ifi.unizh.ch/ailab/aiwiki/aiw.cgi?$1",
-       "ALife" => "http://news.alife.org/wiki/index.php?$1",
-       "AndStuff" => "http://andstuff.org/wiki.php?$1",
-       "Annotation" => "http://bayle.stanford.edu/crit/nph-med.cgi/$1",
-       "AnnotationWiki" => "http://www.seedwiki.com/page.cfm?wikiid=368&doc=$1",
-       "AwarenessWiki" => "http://taoriver.net/aware/$1",
-       "BenefitsWiki" => "http://www.benefitslink.com/cgi-bin/wiki.cgi?$1",
-       "BridgesWiki" => "http://c2.com/w2/bridges/$1",
-       "C2find" => "http://c2.com/cgi/wiki?FindPage&value=$1",
-       "Cache" => "http://www.google.com/search?q=cache:$1",
-       "CLiki" => "http://ww.telent.net/cliki/$1",
-       "CmWiki" => "http://www.ourpla.net/cgi-bin/wiki.pl?$1",
-       "CreationMatters" => "http://www.ourpla.net/cgi-bin/wiki.pl?$1",
-       "DejaNews" => "http://www.deja.com/=dnc/getdoc.xp?AN=$1",
-       "DeWikiPedia" => "http://www.wikipedia.de/wiki.cgi?$1",
-       "Dictionary" => "http://www.dict.org/bin/Dict?Database=*&Form=Dict1&Strategy=*&Query=$1",
-       "DiveIntoOsx" => "http://diveintoosx.org/$1",
-       "DocBook" => "http://docbook.org/wiki/moin.cgi/$1",
-       "DolphinWiki" => "http://www.object-arts.com/wiki/html/Dolphin/$1",
-       "EfnetCeeWiki" => "http://purl.net/wiki/c/$1",
-       "EfnetCppWiki" => "http://purl.net/wiki/cpp/$1",
-       "EfnetPythonWiki" => "http://purl.net/wiki/python/$1",
-       "EfnetXmlWiki" => "http://purl.net/wiki/xml/$1",
-       "EljWiki" => "http://elj.sourceforge.net/phpwiki/index.php/$1",
-       "EmacsWiki" => "http://www.emacswiki.org/cgi-bin/wiki.pl?$1",
-       "FinalEmpire" => "http://final-empire.sourceforge.net/cgi-bin/wiki.pl?$1",
-       "Foldoc" => "http://www.foldoc.org/foldoc/foldoc.cgi?$1",
-       "FoxWiki" => "http://fox.wikis.com/wc.dll?Wiki~$1",
-       "FreeBSDman" => "http://www.FreeBSD.org/cgi/man.cgi?apropos=1&query=$1",
-       "Google" => "http://www.google.com/search?q=$1",
-       "GoogleGroups" => "http://groups.google.com/groups?q=$1",
-       "GreenCheese" => "http://www.greencheese.org/$1",
-       "HammondWiki" => "http://www.dairiki.org/HammondWiki/index.php3?$1",
-       "Haribeau" => "http://wiki.haribeau.de/cgi-bin/wiki.pl?$1",
-       "IAWiki" => "http://www.IAwiki.net/$1",
-       "IMDB" => "http://us.imdb.com/Title?$1",
-       "JargonFile" => "http://sunir.org/apps/meta.pl?wiki=JargonFile&redirect=$1",
-       "JiniWiki" => "http://www.cdegroot.com/cgi-bin/jini?$1",
-       "JspWiki" => "http://www.ecyrd.com/JSPWiki/Wiki.jsp?page=$1",
-       "KmWiki" => "http://www.voght.com/cgi-bin/pywiki?$1",
-       "KnowHow" => "http://www2.iro.umontreal.ca/~paquetse/cgi-bin/wiki.cgi?$1",
-       "LanifexWiki" => "http://opt.lanifex.com/cgi-bin/wiki.pl?$1",
-       "LegoWiki" => "http://www.object-arts.com/wiki/html/Lego-Robotics/$1",
-       "LinuxWiki" => "http://www.linuxwiki.de/$1",
-       "LugKR" => "http://lug-kr.sourceforge.net/cgi-bin/lugwiki.pl?$1",
-       "MathSongsWiki" => "http://SeedWiki.com/page.cfm?wikiid=237&doc=$1",
-       "MbTest" => "http://www.usemod.com/cgi-bin/mbtest.pl?$1",
-       "MeatBall" => "http://www.usemod.com/cgi-bin/mb.pl?$1",
-       "MetaWiki" => "http://sunir.org/apps/meta.pl?$1",
-       "MetaWikiPedia" => "http://meta.wikipedia.com/wiki/$1",
-       "MoinMoin" => "http://purl.net/wiki/moin/$1",
-       "MuWeb" => "http://www.dunstable.com/scripts/MuWebWeb?$1",
-       "NetVillage" => "http://www.netbros.com/?$1",
-       "OpenWiki" => "http://openwiki.com/?$1",
-       "OrgPatterns" => "http://www.bell-labs.com/cgi-user/OrgPatterns/OrgPatterns?$1",
-       "PangalacticOrg" => "http://www.pangalactic.org/Wiki/$1",
-       "PersonalTelco" => "http://www.personaltelco.net/index.cgi/$1",
-       "PhpWiki" => "http://phpwiki.sourceforge.net/phpwiki/index.php?$1",
-       "Pikie" => "http://pikie.darktech.org/cgi/pikie?$1",
-       "PPR" => "http://c2.com/cgi/wiki?$1",
-       "PurlNet" => "http://purl.oclc.org/NET/$1",
-       "PythonInfo" => "http://www.python.org/cgi-bin/moinmoin/$1",
-       "PythonWiki" => "http://www.pythonwiki.de/$1",
-       "PyWiki" => "http://www.voght.com/cgi-bin/pywiki?$1",
-       "SeaPig" => "http://www.seapig.org/ $1",
-       "SeattleWireless" => "http://seattlewireless.net/?$1",
-       "SenseisLibrary" => "http://senseis.xmp.net/?$1",
-       "Shakti" => "http://cgi.algonet.se/htbin/cgiwrap/pgd/ShaktiWiki/$1",
-       "SourceForge" => "http://sourceforge.net/$1",
-       "Squeak" => "http://minnow.cc.gatech.edu/squeak/$1",
-       "StrikiWiki" => "http://ch.twi.tudelft.nl/~mostert/striki/teststriki.pl?$1",
-       "SVGWiki" => "http://www.protocol7.com/svg-wiki/default.asp?$1",
-       "Tavi" => "http://tavi.sourceforge.net/index.php?$1",
-       "TmNet" => "http://www.technomanifestos.net/?$1",
-       "TMwiki" => "http://www.EasyTopicMaps.com/?page=$1",
-       "TWiki" => "http://twiki.org/cgi-bin/view/$1",
-       "TwistedWiki" => "http://purl.net/wiki/twisted/$1",
-       "Unreal" => "http://wiki.beyondunreal.com/wiki/$1",
-       "UseMod" => "http://www.usemod.com/cgi-bin/wiki.pl?$1",
-       "VisualWorks" => "http://wiki.cs.uiuc.edu/VisualWorks/$1",
-       "WebDevWikiNL" => "http://www.promo-it.nl/WebDevWiki/index.php?page=$1",
-       "WebSeitzWiki" => "http://webseitz.fluxent.com/wiki/$1",
-       "Why" => "http://clublet.com/c/c/why?$1",
-       "Wiki" => "http://c2.com/cgi/wiki?$1",
-       "WikiPedia" => "http://www.wikipedia.com/wiki/$1",
-       "WikiWorld" => "http://WikiWorld.com/wiki/index.php/$1",
-       "YpsiEyeball" => "http://sknkwrks.dyndns.org:1957/writewiki/wiki.pl?$1",
-       "ZWiki" => "http://www.zwiki.org/$1",
+/**
+ * The interwiki class
+ * All information is loaded on creation when called by Interwiki::fetch( $prefix ).
+ * All work is done on slave, because this should *never* change (except during
+ * schema updates etc, which aren't wiki-related)
+ */
+class Interwiki {
 
-       # Some custom additions:
-       "ReVo"  =>      "http://purl.org/NET/voko/revo/art/$1.html",
-         # eg [[ReVo:cerami]], [[ReVo:astero]] - note X-sensitive!
-       "EcheI" =>      "http://www.ikso.net/cgi-bin/wiki.pl?$1",
-       "E\xc4\x89eI" =>        "http://www.ikso.net/cgi-bin/wiki.pl?$1",
-       "UnuMondo"      =>      "http://unumondo.com/cgi-bin/wiki.pl?$1", # X-sensitive!
-       "JEFO"  =>      "http://esperanto.jeunes.free.fr/vikio/index.php?$1",
-       "PMEG"  =>      "http://www.bertilow.com/pmeg/$1.php",
-               # ekz [[PMEG:gramatiko/kunligaj vortetoj/au]]
-       "EnciclopediaLibre" => "http://enciclopedia.us.es/wiki.phtml?title=$1",
+       // Cache - removes oldest entry when it hits limit
+       protected static $smCache = array();
+       const CACHE_LIMIT = 100; // 0 means unlimited, any other value is max number of entries.
 
-       # Wikipedia-specific stuff:
-       # Special cases
-       "w"             => "http://www.wikipedia.org/wiki/$1",
-       "m"             => "http://meta.wikipedia.org/wiki/$1",
-       "meta"          => "http://meta.wikipedia.org/wiki/$1",
-       "sep11"         => "http://sep11.wikipedia.org/wiki/$1",
-       "simple"=> "http://simple.wikipedia.com/wiki.cgi?$1",
-       "wiktionary"    => "http://wiktionary.wikipedia.org/wiki/$1",
+       protected $mPrefix, $mURL, $mAPI, $mWikiID, $mLocal, $mTrans;
 
-       # ISO 639 2-letter language codes
-       "aa"    => "http://aa.wikipedia.com/wiki.cgi?$1",
-       "ab"    => "http://ab.wikipedia.com/wiki.cgi?$1",
-       "af"    => "http://af.wikipedia.com/wiki.cgi?$1",
-       "am"    => "http://am.wikipedia.com/wiki.cgi?$1",
-       "ar"    => "http://ar.wikipedia.com/wiki.cgi?$1",
-       "as"    => "http://as.wikipedia.com/wiki.cgi?$1",
-       "ay"    => "http://ay.wikipedia.com/wiki.cgi?$1",
-       "az"    => "http://az.wikipedia.com/wiki.cgi?$1",
-       "ba"    => "http://ba.wikipedia.com/wiki.cgi?$1",
-       "be"    => "http://be.wikipedia.com/wiki.cgi?$1",
-       "bh"    => "http://bh.wikipedia.com/wiki.cgi?$1",
-       "bi"    => "http://bi.wikipedia.com/wiki.cgi?$1",
-       "bn"    => "http://bn.wikipedia.com/wiki.cgi?$1",
-       "bs"    => "http://bs.wikipedia.org/wiki/$1",
-       "bo"    => "http://bo.wikipedia.com/wiki.cgi?$1",
-       "ca"    => "http://ca.wikipedia.com/wiki.cgi?$1",
-       "co"    => "http://co.wikipedia.com/wiki.cgi?$1",
-       "cs"    => "http://cs.wikipedia.org/wiki/$1",
-       "cy"    => "http://cy.wikipedia.com/wiki.cgi?$1",
-       "da"    => "http://da.wikipedia.org/wiki/$1",
-       "de"    => "http://de.wikipedia.org/wiki/$1",
-       "dk"    => "http://da.wikipedia.org/wiki/$1",
-       "dz"    => "http://dz.wikipedia.com/wiki.cgi?$1",
-       "el"    => "http://el.wikipedia.org/wiki/$1",
-       "en"    => "http://www.wikipedia.org/wiki/$1",    # May in future be renamed to en.wikipedia.org; should work as alternate
-       "eo"    => "http://eo.wikipedia.org/wiki/$1",
-       "es"    => "http://es.wikipedia.org/wiki/$1",
-       "et"    => "http://et.wikipedia.com/wiki.cgi?$1",
-       "eu"    => "http://eu.wikipedia.com/wiki.cgi?$1",
-       "fa"    => "http://fa.wikipedia.com/wiki.cgi?$1",
-       "fi"    => "http://fi.wikipedia.com/wiki.cgi?$1",
-       "fj"    => "http://fj.wikipedia.com/wiki.cgi?$1",
-       "fo"    => "http://fo.wikipedia.com/wiki.cgi?$1",
-       "fr"    => "http://fr.wikipedia.org/wiki/$1",
-       "fy"    => "http://fy.wikipedia.com/wiki.cgi?$1",
-       "ga"    => "http://ga.wikipedia.com/wiki.cgi?$1",
-       "gl"    => "http://gl.wikipedia.com/wiki.cgi?$1",
-       "gn"    => "http://gn.wikipedia.com/wiki.cgi?$1",
-       "gu"    => "http://gu.wikipedia.com/wiki.cgi?$1",
-       "ha"    => "http://ha.wikipedia.com/wiki.cgi?$1",
-       "he"    => "http://he.wikipedia.com/wiki.cgi?$1",
-       "hi"    => "http://hi.wikipedia.com/wiki.cgi?$1",
-       "hr"    => "http://hr.wikipedia.org/wiki/$1",
-       "hu"    => "http://hu.wikipedia.com/wiki.cgi?$1",
-       "hy"    => "http://hy.wikipedia.com/wiki.cgi?$1",
-       "ia"    => "http://ia.wikipedia.com/wiki.cgi?$1",
-       "id"    => "http://id.wikipedia.com/wiki.cgi?$1",
-       "ik"    => "http://ik.wikipedia.com/wiki.cgi?$1",
-       "is"    => "http://is.wikipedia.com/wiki.cgi?$1",
-       "it"    => "http://it.wikipedia.com/wiki.cgi?$1",
-       "iu"    => "http://iu.wikipedia.com/wiki.cgi?$1",
-       "ja"    => "http://ja.wikipedia.org/wiki/$1",
-       "jv"    => "http://jv.wikipedia.com/wiki.cgi?$1",
-       "ka"    => "http://ka.wikipedia.com/wiki.cgi?$1",
-       "kk"    => "http://kk.wikipedia.com/wiki.cgi?$1",
-       "kl"    => "http://kl.wikipedia.com/wiki.cgi?$1",
-       "km"    => "http://km.wikipedia.com/wiki.cgi?$1",
-       "kn"    => "http://kn.wikipedia.com/wiki.cgi?$1",
-       "ko"    => "http://ko.wikipedia.org/wiki/$1",
-       "ks"    => "http://ks.wikipedia.com/wiki.cgi?$1",
-       "ku"    => "http://ku.wikipedia.com/wiki.cgi?$1",
-       "ky"    => "http://ky.wikipedia.com/wiki.cgi?$1",
-       "la"    => "http://la.wikipedia.com/wiki.cgi?$1",
-       "lo"    => "http://lo.wikipedia.com/wiki.cgi?$1",
-       "lv"    => "http://lv.wikipedia.com/wiki.cgi?$1",
-       "mg"    => "http://mg.wikipedia.com/wiki.cgi?$1",
-       "mi"    => "http://mi.wikipedia.com/wiki.cgi?$1",
-       "mk"    => "http://mk.wikipedia.com/wiki.cgi?$1",
-       "ml"    => "http://ml.wikipedia.org/wiki/$1",
-       "mn"    => "http://mn.wikipedia.com/wiki.cgi?$1",
-       "mo"    => "http://mo.wikipedia.com/wiki.cgi?$1",
-       "mr"    => "http://mr.wikipedia.com/wiki.cgi?$1",
-       "ms"    => "http://ms.wikipedia.org/wiki/$1",
-       "my"    => "http://my.wikipedia.com/wiki.cgi?$1",
-       "na"    => "http://na.wikipedia.com/wiki.cgi?$1",
-       "ne"    => "http://ne.wikipedia.com/wiki.cgi?$1",
-       "nl"    => "http://nl.wikipedia.org/wiki/$1",
-       "no"    => "http://no.wikipedia.com/wiki.cgi?$1",
-       "oc"    => "http://oc.wikipedia.com/wiki.cgi?$1",
-       "om"    => "http://om.wikipedia.com/wiki.cgi?$1",
-       "or"    => "http://or.wikipedia.com/wiki.cgi?$1",
-       "pa"    => "http://pa.wikipedia.com/wiki.cgi?$1",
-       "pl"    => "http://pl.wikipedia.org/wiki/$1",
-       "ps"    => "http://ps.wikipedia.com/wiki.cgi?$1",
-       "pt"    => "http://pt.wikipedia.com/wiki.cgi?$1",
-       "qu"    => "http://qu.wikipedia.com/wiki.cgi?$1",
-       "rm"    => "http://rm.wikipedia.com/wiki.cgi?$1",
-       "rn"    => "http://rn.wikipedia.com/wiki.cgi?$1",
-       "ro"    => "http://ro.wikipedia.com/wiki.cgi?$1",
-       "ru"    => "http://ru.wikipedia.org/wiki/$1",
-       "rw"    => "http://rw.wikipedia.com/wiki.cgi?$1",
-       "sa"    => "http://sa.wikipedia.com/wiki.cgi?$1",
-       "sd"    => "http://sd.wikipedia.com/wiki.cgi?$1",
-       "sg"    => "http://sg.wikipedia.com/wiki.cgi?$1",
-       "sh"    => "http://sh.wikipedia.org/wiki/$1",
-       "si"    => "http://si.wikipedia.com/wiki.cgi?$1",
-       "sk"    => "http://sk.wikipedia.com/wiki.cgi?$1",
-       "sl"    => "http://sl.wikipedia.com/wiki.cgi?$1",
-       "sm"    => "http://sm.wikipedia.com/wiki.cgi?$1",
-       "sn"    => "http://sn.wikipedia.com/wiki.cgi?$1",
-       "so"    => "http://so.wikipedia.com/wiki.cgi?$1",
-       "sq"    => "http://sq.wikipedia.com/wiki.cgi?$1",
-       "sr"    => "http://sr.wikipedia.org/wiki/$1",
-       "ss"    => "http://ss.wikipedia.com/wiki.cgi?$1",
-       "st"    => "http://st.wikipedia.com/wiki.cgi?$1",
-       "su"    => "http://su.wikipedia.com/wiki.cgi?$1",
-       "sv"    => "http://sv.wikipedia.org/wiki/$1",
-       "sw"    => "http://sw.wikipedia.com/wiki.cgi?$1",
-       "ta"    => "http://ta.wikipedia.com/wiki.cgi?$1",
-       "te"    => "http://te.wikipedia.com/wiki.cgi?$1",
-       "tg"    => "http://tg.wikipedia.com/wiki.cgi?$1",
-       "th"    => "http://th.wikipedia.com/wiki.cgi?$1",
-       "ti"    => "http://ti.wikipedia.com/wiki.cgi?$1",
-       "tk"    => "http://tk.wikipedia.com/wiki.cgi?$1",
-       "tl"    => "http://tl.wikipedia.com/wiki.cgi?$1",
-       "tn"    => "http://tn.wikipedia.com/wiki.cgi?$1",
-       "to"    => "http://to.wikipedia.com/wiki.cgi?$1",
-       "tr"    => "http://tr.wikipedia.org/wiki/$1",
-       "ts"    => "http://ts.wikipedia.com/wiki.cgi?$1",
-       "tt"    => "http://tt.wikipedia.com/wiki.cgi?$1",
-       "tw"    => "http://tw.wikipedia.com/wiki.cgi?$1",
-       "ug"    => "http://ug.wikipedia.com/wiki.cgi?$1",
-       "uk"    => "http://uk.wikipedia.com/wiki.cgi?$1",
-       "ur"    => "http://ur.wikipedia.com/wiki.cgi?$1",
-       "uz"    => "http://uz.wikipedia.com/wiki.cgi?$1",
-       "vi"    => "http://vi.wikipedia.com/wiki.cgi?$1",
-       "vo"    => "http://vo.wikipedia.com/wiki.cgi?$1",
-       "wo"    => "http://wo.wikipedia.com/wiki.cgi?$1",
-       "xh"    => "http://xh.wikipedia.com/wiki.cgi?$1",
-       "yi"    => "http://yi.wikipedia.com/wiki.cgi?$1",
-       "yo"    => "http://yo.wikipedia.com/wiki.cgi?$1",
-       "za"    => "http://za.wikipedia.com/wiki.cgi?$1",
-       "zh"    => "http://zh.wikipedia.org/wiki/$1",
-       "zu"    => "http://zu.wikipedia.com/wiki.cgi?$1"
-);
-?>
+       public function __construct( $prefix = null, $url = '', $api = '', $wikiId = '', $local = 0, $trans = 0 ) {
+               $this->mPrefix = $prefix;
+               $this->mURL = $url;
+               $this->mAPI = $api;
+               $this->mWikiID = $wikiId;
+               $this->mLocal = $local;
+               $this->mTrans = $trans;
+       }
+
+       /**
+        * Check whether an interwiki prefix exists
+        *
+        * @param $prefix String: interwiki prefix to use
+        * @return Boolean: whether it exists
+        */
+       static public function isValidInterwiki( $prefix ) {
+               $result = self::fetch( $prefix );
+               return (bool)$result;
+       }
+
+       /**
+        * Fetch an Interwiki object
+        *
+        * @param $prefix String: interwiki prefix to use
+        * @return Interwiki Object, or null if not valid
+        */
+       static public function fetch( $prefix ) {
+               global $wgContLang;
+               if( $prefix == '' ) {
+                       return null;
+               }
+               $prefix = $wgContLang->lc( $prefix );
+               if( isset( self::$smCache[$prefix] ) ) {
+                       return self::$smCache[$prefix];
+               }
+               global $wgInterwikiCache;
+               if( $wgInterwikiCache ) {
+                       $iw = Interwiki::getInterwikiCached( $prefix );
+               } else {
+                       $iw = Interwiki::load( $prefix );
+                       if( !$iw ) {
+                               $iw = false;
+                       }
+               }
+               if( self::CACHE_LIMIT && count( self::$smCache ) >= self::CACHE_LIMIT ) {
+                       reset( self::$smCache );
+                       unset( self::$smCache[key( self::$smCache )] );
+               }
+               self::$smCache[$prefix] = $iw;
+               return $iw;
+       }
+
+       /**
+        * Fetch interwiki prefix data from local cache in constant database.
+        *
+        * @note More logic is explained in DefaultSettings.
+        *
+        * @param $prefix String: interwiki prefix
+        * @return Interwiki object
+        */
+       protected static function getInterwikiCached( $prefix ) {
+               $value = self::getInterwikiCacheEntry( $prefix );
+
+               $s = new Interwiki( $prefix );
+               if ( $value != '' ) {
+                       // Split values
+                       list( $local, $url ) = explode( ' ', $value, 2 );
+                       $s->mURL = $url;
+                       $s->mLocal = (int)$local;
+               } else {
+                       $s = false;
+               }
+               return $s;
+       }
+
+       /**
+        * Get entry from interwiki cache
+        *
+        * @note More logic is explained in DefaultSettings.
+        *
+        * @param $prefix String: database key
+        * @return String: the entry
+        */
+       protected static function getInterwikiCacheEntry( $prefix ) {
+               global $wgInterwikiCache, $wgInterwikiScopes, $wgInterwikiFallbackSite;
+               static $db, $site;
+
+               wfDebug( __METHOD__ . "( $prefix )\n" );
+               if( !$db ) {
+                       $db = CdbReader::open( $wgInterwikiCache );
+               }
+               /* Resolve site name */
+               if( $wgInterwikiScopes >= 3 && !$site ) {
+                       $site = $db->get( '__sites:' . wfWikiID() );
+                       if ( $site == '' ) {
+                               $site = $wgInterwikiFallbackSite;
+                       }
+               }
+
+               $value = $db->get( wfMemcKey( $prefix ) );
+               // Site level
+               if ( $value == '' && $wgInterwikiScopes >= 3 ) {
+                       $value = $db->get( "_{$site}:{$prefix}" );
+               }
+               // Global Level
+               if ( $value == '' && $wgInterwikiScopes >= 2 ) {
+                       $value = $db->get( "__global:{$prefix}" );
+               }
+               if ( $value == 'undef' ) {
+                       $value = '';
+               }
+
+               return $value;
+       }
+
+       /**
+        * Load the interwiki, trying first memcached then the DB
+        *
+        * @param $prefix The interwiki prefix
+        * @return Boolean: the prefix is valid
+        */
+       protected static function load( $prefix ) {
+               global $wgMemc, $wgInterwikiExpiry;
+
+               $iwData = false;
+               if ( !wfRunHooks( 'InterwikiLoadPrefix', array( $prefix, &$iwData ) ) ) {
+                       return Interwiki::loadFromArray( $iwData );
+               }
+
+               if ( !$iwData ) {
+                       $key = wfMemcKey( 'interwiki', $prefix );
+                       $iwData = $wgMemc->get( $key );
+               }
+
+               if( $iwData && is_array( $iwData ) ) { // is_array is hack for old keys
+                       $iw = Interwiki::loadFromArray( $iwData );
+                       if( $iw ) {
+                               return $iw;
+                       }
+               }
+
+               $db = wfGetDB( DB_SLAVE );
+
+               $row = $db->fetchRow( $db->select( 'interwiki', '*', array( 'iw_prefix' => $prefix ),
+                       __METHOD__ ) );
+               $iw = Interwiki::loadFromArray( $row );
+               if ( $iw ) {
+                       $mc = array(
+                               'iw_url' => $iw->mURL,
+                               'iw_api' => $iw->mAPI,
+                               'iw_local' => $iw->mLocal,
+                               'iw_trans' => $iw->mTrans
+                       );
+                       $wgMemc->add( $key, $mc, $wgInterwikiExpiry );
+                       return $iw;
+               }
+
+               return false;
+       }
+
+       /**
+        * Fill in member variables from an array (e.g. memcached result, Database::fetchRow, etc)
+        *
+        * @param $mc Associative array: row from the interwiki table
+        * @return Boolean: whether everything was there
+        */
+       protected static function loadFromArray( $mc ) {
+               if( isset( $mc['iw_url'] ) && isset( $mc['iw_local'] ) && isset( $mc['iw_trans'] ) ) {
+                       $iw = new Interwiki();
+                       $iw->mURL = $mc['iw_url'];
+                       $iw->mLocal = $mc['iw_local'];
+                       $iw->mTrans = $mc['iw_trans'];
+                       $iw->mAPI = isset( $mc['iw_api'] ) ? $mc['iw_api'] : '';
+                       $iw->mWikiID = isset( $mc['iw_wikiid'] ) ? $mc['iw_wikiid'] : '';
+
+                       return $iw;
+               }
+               return false;
+       }
+
+       /**
+        * Get the URL for a particular title (or with $1 if no title given)
+        *
+        * @param $title String: what text to put for the article name
+        * @return String: the URL
+        */
+       public function getURL( $title = null ) {
+               $url = $this->mURL;
+               if( $title != null ) {
+                       $url = str_replace( "$1", $title, $url );
+               }
+               return $url;
+       }
+
+       /**
+        * Get the API URL for this wiki
+        *
+        * @return String: the URL
+        */
+       public function getAPI() {
+               return $this->mAPI;
+       }
+
+       /**
+        * Get the DB name for this wiki
+        *
+        * @return String: the DB name
+        */
+       public function getWikiID() {
+               return $this->mWikiID;
+       }
+
+       /**
+        * Is this a local link from a sister project, or is
+        * it something outside, like Google
+        *
+        * @return Boolean
+        */
+       public function isLocal() {
+               return $this->mLocal;
+       }
+
+       /**
+        * Can pages from this wiki be transcluded?
+        * Still requires $wgEnableScaryTransclusion
+        *
+        * @return Boolean
+        */
+       public function isTranscludable() {
+               return $this->mTrans;
+       }
+
+       /**
+        * Get the name for the interwiki site
+        *
+        * @return String
+        */
+       public function getName() {
+               $msg = wfMessage( 'interwiki-name-' . $this->mPrefix )->inContentLanguage();
+               return !$msg->exists() ? '' : $msg;
+       }
+
+       /**
+        * Get a description for this interwiki
+        *
+        * @return String
+        */
+       public function getDescription() {
+               $msg = wfMessage( 'interwiki-desc-' . $this->mPrefix )->inContentLanguage();
+               return !$msg->exists() ? '' : $msg;
+       }
+}