PHP5.x升级到PHP7.x后MediaWiki网站出现的问题

　　前两周同事开始对阿里云服务器上的PHP 5升级为PHP 7，遇到的问题以及解决办法我记录在《PHP5.x升级到PHP7.x后Drupal网站出现的问题》一文中，本周对MediaWiki所在服务器要进行升级，所以先进行了一些测试，把Wiki站文件复制到已经升级为PHP 7.3.5的服务器上，马上看到了一堆报错，逐个去检查、搜索、修改以致全部解决，下面也来进行一些记录。

　　首先在MediaWiki官方网站上找到MediaWiki各个版本对PHP的要求，我们目前的MediaWiki 1.27支持PHP 5.5.9+, 5.6.x, 7.0.x, 7.1.x，并没有说支持7.2.x或者7.3.x，更多的第三方开发的扩展程序编写时间更老、版本更新不及时，估计对PHP的兼容性也更差，程序总是需要修改的，所以我们干脆就把MediaWiki 1.27直接放在安装好PHP 7.3.5的服务器上。一些错误如下：

　　1.27核心程序的报错：

• LocalisationCache.php报错：这里找到解决办法，修改mediawiki/core / includes/cache/localisation/LocalisationCache.php文件；

　　还有很多类似这样的报错：

Warning: Parameter 1 to setupMetaDescriptionTagParserHooks() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to SyntaxHighlight_GeSHi::onParserFirstCallInit() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to PdfHandler::registerWarningModule() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to InputBoxHooks::register() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to ImageMap::onParserFirstCallInit() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to GoogleRichCards() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to GadgetHooks::registerModules() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to ExtVariables::onParserClearState() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to ExtVariables::onInternalParseBeforeSanitize() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to ExtVariables::init() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to ExtLoops::onParserClearState() expected to be a reference, value given in includes/Hooks.php on line 195
Warning: Parameter 1 to ExtLoops::init() expected to be a reference, value given in includes/Hooks.php on line 195

　　查看Hooks.php文件195行也没有什么特别，在Google中搜索“Warning: Parameter 1 to  expected to be a reference, value given in Hooks.php on line 195”，都是说需要修改对应的第三方扩展中的public static function函数定义写法，将&$this替换为$this，涉及到下面一些内容：

　　1.27发行版本带的扩展程序的报错：

• ConfirmEdit/includes/ConfirmEditHooks.php
• Gadgets/GadgetHooks.php
• ImageMap/ImageMap_body.php
• InputBox/InputBox.hooks.php
• ParserFunctions/ParserFunctions.hooks.php
• PdfHandler/PdfHandler_body.php
• SyntaxHighlight_GeSHi/SyntaxHighlight_GeSHi.class.php

　　我们自行下载安装的扩展程序的报错：

• GoogleRichCards/GoogleRichCards.php
• Loops/Loops.php
• MetaDescriptionTag/MetaDescriptionTag.php
• Variables/Variables.php
• Include/Include.php
• Memcached/Memcached.php (修改办法稍微有点不一样，来源：https://www.mediawiki.org/wiki/Extension_talk:Memcached )

　　我们自己开发的扩展中的报错：

• ZhConvert/ZhConvert.php

　　这个过程还在进行中，后面发现新的问题会及时更新本文。

其它的错误：

Deprecated: The each() function is deprecated. This message will be suppressed on further calls in mediawiki_code-1.27.0/includes/MagicWordArray.php on line 197

修改includes/MagicWordArray.php on line 197

//jamesqi 2019-6-19 while (list( $key, $value ) = each( $m ) ) {
foreach ( $m as $key => $value ) {

再有这样的报错：

Deprecated: assert(): Calling assert() with a string argument is deprecated in mediawiki_code-1.27.0/includes/parser/Preprocessor_DOM.phpon line 542

修改includes/parser/Preprocessor_DOM.phpon line 542

// A heading must be open, otherwise \n wouldn't have been in the search list
//jamesqi 2019-6-19//assert( '$piece->open == "\n"' );
$piece->open == "\n";
$part = $piece->getCurrentPart();

再一个报错：

Warning: session_id(): Cannot change session id when session is active in mediawiki_code-1.27.0/includes/Setup.php on line 773

暂未解决

　　2019-6-18补充：还可以在程序中添加：error_reporting(E_ALL ^ E_DEPRECATED); 来让这种报错不显示，或者在php.ini里面设置error_reporting = E_ALL &~E_NOTICE &~E_DEPRECATED。