MediaWiki

Note: MediaWiki is not fully compatible with PHP 7.3 yet.[1][2]

MediaWiki is a free and open source wiki software written in PHP, originally developed for Wikipedia. It also powers this wiki (see Special:Version and the GitHub repository).

Installation

To run MediaWiki you need three things:

• the mediawiki package, which pulls in PHP
• a web server – Apache, Nginx or Lighttpd
• a database system – MySQL, PostgreSQL or SQLite

To install MediaWiki on XAMPP, see mw:Manual:Installing MediaWiki on XAMPP

Configuration

The steps to achieve a working MediaWiki configuration involve editing the PHP settings and adding the MediaWiki configuration snippets.

PHP

MediaWiki requires the iconv extension, so you need to uncomment extension=iconv in /etc/php/php.ini.

Optional dependencies:

• For thumbnail rendering, install either ImageMagick or php-gd. If you choose the latter, you also need to uncomment extension=gd.
• For more efficient Unicode normalization, install php-intl and uncomment extension=intl.

Enable the API for your DBMS:

• If you use MariaDB, uncomment extension=mysqli.
• If you use PostgreSQL, install php-pgsql and uncomment extension=pgsql.
• If you use SQLite, install php-sqlite and uncomment extension=pdo_sqlite.

Second, tweak the session handling or you might get a fatal error (PHP Fatal error: session_start(): Failed to initialize storage module[...]) by finding the session.save_path path. A good choice can be /var/lib/php/sessions or /tmp/.

/etc/php/php.ini

session.save_path = "/var/lib/php/sessions"

You will need to create the directory if it does not exist and then restrict its permissions:

# mkdir -p /var/lib/php/sessions/
# chown http:http /var/lib/php/sessions
# chmod go-rwx /var/lib/php/sessions

If you use PHP's open_basedir and want to allow file uploads, you need to include /var/lib/mediawiki/ (mediawiki symlinks images/ to /var/lib/mediawiki/).

Web server

Apache

Follow Apache HTTP Server#PHP.

Copy /etc/webapps/mediawiki/apache.example.conf to /etc/httpd/conf/extra/mediawiki.conf and edit it as needed.

Add the following line to /etc/httpd/conf/httpd.conf:

Include conf/extra/mediawiki.conf

Restart the httpd.service daemon.

Note: The default file from /etc/webapps/mediawiki/apache.example.conf will overwrite the PHP open_basedir setting, possibly conflicting with other pages. This behavior can be changed by moving line starting with php_admin_value between the <Directory> tags. Further, if you are running multiple applications that depend on the same server, this value could also be added to the open_basedir value in /etc/php/php.ini instead of /etc/httpd/conf/extra/mediawiki.conf

Nginx

To get MediaWiki working with Nginx, create the following file:

/etc/nginx/mediawiki.conf

location / {
   index index.php;
   try_files $uri $uri/ @mediawiki;
}
location @mediawiki {
   rewrite ^/(.*)$ /index.php;
}
location ~ \.php5?$ {
   include /etc/nginx/fastcgi_params;
   fastcgi_pass unix:/var/run/php-fpm/php-fpm.sock;
   fastcgi_index index.php5;
   fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
   try_files $uri @mediawiki;
}
location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
   try_files $uri /index.php;
   expires max;
   log_not_found off;
}
# Restrictions based on the .htaccess files
location ^~ ^/(cache|includes|maintenance|languages|serialized|tests|images/deleted)/ {
   deny all;
}
location ^~ ^/(bin|docs|extensions|includes|maintenance|mw-config|resources|serialized|tests)/ {
   internal;
}
location ^~ /images/ {
   try_files $uri /index.php;
}
location ~ /\. {
   access_log off;
   log_not_found off; 
   deny all;
}

Ensure that php-fpm is installed and started.

Include a server directive, similar to this

/etc/nginx/nginx.conf

server {
  listen 80;
  server_name mediawiki;
  root /usr/share/webapps/mediawiki;
  index index.php;
  charset utf-8;
# For correct file uploads
  client_max_body_size    100m; # Equal or more than upload_max_filesize in /etc/php/php.ini
  client_body_timeout     60;
  include mediawiki.conf;

}

Finally, restart nginx.service and php-fpm.service daemons.

Lighttpd

You should have Lighttpd installed and configured. "mod_alias" and "mod_rewrite" in server.modules array of lighttpd is required. Append to the lighttpd configuration file the following lines

/etc/lighttpd/lighttpd.conf

alias.url += ("/mediawiki" => "/usr/share/webapps/mediawiki/")
url.rewrite-once += (
                "^/mediawiki/wiki/upload/(.+)" => "/mediawiki/wiki/upload/$1",
                "^/mediawiki/wiki/$" => "/mediawiki/index.php",
                "^/mediawiki/wiki/([^?]*)(?:\?(.*))?" => "/mediawiki/index.php?title=$1&$2"
)

Restart the lighttpd.service daemon.

Database

Set up a database server as explained in the article of your DBMS: MySQL, PostgreSQL or SQLite.

MediaWiki can automatically create the database, if you supply the database root password, during the next step. Otherwise the database needs to be created manually, see upstream instructions.

LocalSettings.php

Open the wiki url (usually http://your_server/mediawiki/) in a browser and do the initial configuration. Follow upstream instructions.

The generated LocalSettings.php file is offered for download, save it to /usr/share/webapps/mediawiki/LocalSettings.php. This file defines the specific settings of your wiki. Whenever you upgrade the mediawiki package, it is not replaced.

Tips and tricks

Mathematics (texvc)

Usually installing texvc and enabling it in the config is enough:

$wgUseTeX = true;

If you get problems, try to increase limits for shell commands:

$wgMaxShellMemory = 8000000;
$wgMaxShellFileSize = 1000000;
$wgMaxShellTime = 300;

Unicode

Check that php, apache and mysql uses UTF-8. Otherwise you may face strange bugs because of encoding mismatch.

VisualEditor

The VisualEditor MediaWiki extension provides a rich-text editor for MediaWiki. Follow mw:Extension:VisualEditor to install it.

You will also need the Parsoid Node.js backend, which is available from the AUR as parsoid-git^AUR.

Adjust the path to MediaWiki in /usr/share/webapps/parsoid/api/localsettings.js:

parsoidConfig.setInterwiki( 'localhost', 'http://localhost/mediawiki/api.php' );

After that enable and start parsoid.service.

Alternatively, one may also use the parsoid^AUR package, and configure the service via the yaml file, where the following lines should be present:

/usr/share/webapps/parsoid/config.yaml

uri: `'http://localhost/mediawiki/api.php'`
domain: 'localhost'

The matching part in the mediawiki settings:

/usr/share/webapps/mediawiki/LocalSettings.php

$wgVirtualRestConfig['modules']['parsoid'] = array(
  // URL to the Parsoid instance - use port 8142 if you use the Debian package - the parameter 'URL' was first used but is now deprecated (string)
  'url' => 'http://localhost:8000/',
  // Parsoid "domain" (string, optional) - MediaWiki >= 1.26
  'domain' => 'localhost',
  // Parsoid "prefix" (string, optional) - deprecated since MediaWiki 1.26, use 'domain'
  'prefix' => 'localhost',
  // Forward cookies in the case of private wikis (string or false, optional)
  'forwardCookies' => false,
  // request timeout in seconds (integer or null, optional)
  'timeout' => null,
  // Parsoid HTTP proxy (string or null, optional)
  'HTTPProxy' => null,
  // whether to parse URL as if they were meant for RESTBase (boolean or null, optional)
  'restbaseCompat' => null,
);

After configuration, the parsoid service may be started (restarted) and (if not done yet) enabled.