globals.txt
-Globals are evil. The original MediaWiki code relied on
-globals for processing context far too often. MediaWiki
-development since then has been a story of slowly moving
-context out of global variables and into objects. Storing
-processing context in object member variables allows those
-objects to be reused in a much more flexible way. Consider
-the elegance of:
+Globals are evil. The original MediaWiki code relied on globals for processing
+context far too often. MediaWiki development since then has been a story of
+slowly moving context out of global variables and into objects. Storing
+processing context in object member variables allows those objects to be reused
+in a much more flexible way. Consider the elegance of:
# Generate the article HTML as if viewed by a web request
$article = new Article( Title::newFromText( $t ) );
$article->view();
-
+
versus
# Save current globals
$wgTitle = $oldTitle
$wgArticle = $oldArticle
-Some of the current MediaWiki developers have an idle
-fantasy that some day, globals will be eliminated from
-MediaWiki entirely, replaced by an application object which
-would be passed to constructors. Whether that would be an
-efficient, convenient solution remains to be seen, but
-certainly PHP 5 makes such object-oriented programming
-models easier than they were in previous versions.
-
-For the time being though, MediaWiki programmers will have
-to work in an environment with some global context. At the
-time of writing, 418 globals were initialised on startup by
-MediaWiki. 304 of these were configuration settings, which
-are documented in DefaultSettings.php. There is no
-comprehensive documentation for the remaining 114 globals,
-however some of the most important ones are listed below.
-They are typically initialised either in index.php or in
+Some of the current MediaWiki developers have an idle fantasy that some day,
+globals will be eliminated from MediaWiki entirely, replaced by an application
+object which would be passed to constructors. Whether that would be an
+efficient, convenient solution remains to be seen, but certainly PHP 5 makes
+such object-oriented programming models easier than they were in previous
+versions.
+
+For the time being though, MediaWiki programmers will have to work in an
+environment with some global context. At the time of writing, 418 globals were
+initialised on startup by MediaWiki. 304 of these were configuration settings,
+which are documented in DefaultSettings.php. There is no comprehensive
+documentation for the remaining 114 globals, however some of the most important
+ones are listed below. They are typically initialised either in index.php or in
Setup.php.
+For a description of the classes, see design.txt.
+
+$wgTitle
+ Title object created from the request URL.
$wgOut
OutputPage object for HTTP response.
$wgUser
- User object for the user associated with the current
- request.
-
-$wgTitle
- Title object created from the request URL.
+ User object for the user associated with the current request.
$wgLang
- Language object selected by user preferences
+ Language object selected by user preferences.
$wgContLang
- Language object associated with the wiki being
- viewed.
-
-$wgArticle
- Article object corresponding to $wgTitle.
+ Language object associated with the wiki being viewed.
$wgParser
- Parser object. Parser extensions register their
- hooks here.
+ Parser object. Parser extensions register their hooks here.
+
+$wgRequest
+ WebRequest object, to get request data
-$wgLoadBalancer
- A LoadBalancer object, manages database connections.
+$wgMemc, $messageMemc, $parserMemc
+ Object caches