Extension:Scribunto
Scribunto Release status: stable |
|
---|---|
Implementation | Parser extension |
Description | Provides a framework for embedding scripting languages into MediaWiki pages |
Author(s) |
|
Latest version | Continuous updates |
Compatibility policy | Snapshots releases along with MediaWiki. Master is not backward compatible. |
MediaWiki | >= 1.43 |
PHP | 5.5+ |
License | GPL-2.0-or-later AND MIT |
Download | |
Module (ns:828), Talk_Module (ns:829) |
|
|
|
Quarterly downloads | 429 (Ranked 7th) |
Public wikis using | 8,789 (Ranked 30th) |
Translate the Scribunto extension if it is available at translatewiki.net | |
Vagrant role | scribunto |
Issues | Open tasks · Report a bug |
The Scribunto (Latin: "they shall write/let them write (in the future)") extension allows for embedding scripting languages in MediaWiki.
Currently the only supported scripting language is Lua. Scribunto Lua scripts go in a namespace called Module. Modules are run on normal wiki pages using the #invoke parser function and each module has a collection of functions, which can be called using wikitext syntax such as:
{{#invoke: Module_name | function_name | arg1 | arg2 | arg3 ... }}
License
editThis extension contains code licensed GNU General Public License v2.0 or later (GPL-2.0+) as well as code licensed MIT License (MIT).
Requirements
editPCRE version compatibility
editPCRE 8.33+ is recommended. PCRE 8.33 was released in May 2013. You can see the version of PCRE used by PHP by viewing a phpinfo() web page, or from the command line with the following command:
php -r 'echo "pcre: " . ( extension_loaded( "pcre" ) ? PCRE_VERSION : "no" ) . "\n";'
- Scribunto will not work with versions of PCRE lower than 8.10.
- PCRE 8.32 has a bug that will cause it to reject certain non-character codepoints, which will cause errors in the mw.html module.
CentOS 6 and RHEL 6 are stuck on PCRE 7 and need to be upgraded.
Updating to 8.33 on a server with an older version may be relatively complicated. See Updating to PCRE 8.33 or Higher for details.
MediaWiki versions: | 1.25 – 1.28 |
Scribunto versions for MediaWiki 1.25 to 1.28 required PHP's pcntl extension, which is only available on Unix/Linux platforms, if you want to use "LuaStandalone" (i.e. running in a separate child process). This requirement was removed in Scribunto for MediaWiki 1.29.
You can check whether pcntl support is enabled by viewing a phpinfo() web page, or from the command line with the following command:
php -r 'echo "pcntl: " . ( extension_loaded( "pcntl" ) ? "yes" : "no" ) . "\n";'
PHP mbstring extension
editPHP needs to have the mbstring extension enabled.
You can check whether mbstring support is enabled by viewing a phpinfo() web page, or from the command line with the following command:
php -r 'echo "mbstring: " . ( extension_loaded( "mbstring" ) ? "yes" : "no" ) . "\n";'
Lua binary
editBundled binaries
editScribunto comes bundled with Lua binary distributions for Linux (x86 and x86-64), Mac OS X Lion, and Windows (32- and 64-bit).
Scribunto should work for you out of the box if:
- Your web server is run on one of the above platforms.
- PHP's
proc_open
function is not restricted.[1] proc_terminate
andshell_exec
are not disabled in PHP.- Your web server is configured to allow the execution of binary files in the MediaWiki tree.
- Note: Execute permissions may need to be set; for example, in Linux use:
- If you are using SELinux in "Enforcing" mode on your server, you might need to set a proper context for the binaries. Example for RHEL/CentOS 7:
chmod 755 /path/to/extensions/Scribunto/includes/Engines/LuaStandalone/binaries/lua5_1_5_linux_64_generic/lua
chcon -t httpd_sys_script_exec_t /path/to/extensions/Scribunto/includes/Engines/LuaStandalone/binaries/lua5_1_5_linux_64_generic/lua
P.S. Check your version of the extension to see if the name of the engines folder is capitalised or fully lowercase.[2]
Additional binaries
editAdditional Lua binary distributions, which may be needed for your web server if its operating system is not in the list above, can be obtained from http://luabinaries.sourceforge.net/ or from your Linux distribution.
Only binary files for Lua 5.1.x are supported.
Once you've installed the appropriate binary file on your web server, configure the location of the file with:
# Where Lua is the name of the binary file
# e.g. SourceForge LuaBinaries 5.1.5 - Release 2 name the binary file lua5.1
$wgScribuntoEngineConf['luastandalone']['luaPath'] = '/path/to/binaries/lua5.1';
Note that you should not add the above line unless you've confirmed that Scribunto's built-in binaries don't work for you.
LuaJIT, although theoretically compatible, is not supported.
The support was removed due to Spectre and bitrot concerns (phab:T184156).
Installation
edit- Download and move the extracted
Scribunto
folder to yourextensions/
directory.
Developers and code contributors should install the extension from Git instead, using:cd extensions/
git clone https://gerrit.wikimedia.org/r/mediawiki/extensions/Scribunto - Add the following code at the bottom of your LocalSettings.php file:
wfLoadExtension( 'Scribunto' ); $wgScribuntoDefaultEngine = 'luastandalone';
- Set execute permissions for the Lua binaries bundled with this extension:
chmod a+x /path/to/extensions/Scribunto/includes/Engines/LuaStandalone/binaries/yourOS/lua
- Set type to
httpd_sys_script_exec_t
if SELinux is enforced:
chcon -t httpd_sys_script_exec_t /path/to/extensions/Scribunto/includes/Engines/LuaStandalone/binaries/yourOS/lua
- Done – Navigate to Special:Version on your wiki to verify that the extension is successfully installed.
Vagrant installation:
- If using Vagrant , install with
vagrant roles enable scribunto --provision
Optional installation
editIntegrating extensions
editFor a more pleasant user interface, with syntax highlighting and a code editor with autoindent, install the following extensions:
MediaWiki version: | ≤ 1.30 |
Then in your LocalSettings.php
after all the extension registrations, add:
$wgScribuntoUseGeSHi = true;
$wgScribuntoUseCodeEditor = true;
These settings are not necessary in MediaWiki versions after 1.30, where the code editor and syntax hightlighting should be used in the appropriate places automatically once the extensions are loaded. However, other settings may be desired. See the documentation for each extension.
LuaSandbox
editWe have developed a PHP extension written in C called LuaSandbox. It can be used as an alternative to the standalone binary, and will provide improved performance. See LuaSandbox for details and installation instructions.
If you initially installed the extension to use the Lua standalone binary, be sure to update LocalSettings.php
with the following configuration setting:
$wgScribuntoDefaultEngine = 'luasandbox';
Configuration
editThe following configuration variables are available:
- $wgScribuntoDefaultEngine
- Select the engine. Valid values are the keys in
$wgScribuntoEngineConf
, which by default are'luasandbox'
or'luastandalone'
. - $wgScribuntoUseGeSHi
- When Extension:SyntaxHighlight is installed, set this true to use it when displaying Module pages. (MediaWiki 1.30 or earlier.)
- $wgScribuntoUseCodeEditor
- When Extension:CodeEditor is installed, set this
true
to use it when editing Module pages. (MediaWiki 1.30 or earlier.) - $wgScribuntoEngineConf
- An associative array for engine configuration. Keys are the valid values for
$wgScribuntoDefaultEngine
, and values are associative arrays of configuration data. Each configuration array must contain a'class'
key naming theScribuntoEngineBase
subclass to use.
LuaStandalone
editThe following keys are used in $wgScribuntoEngineConf
for Scribunto_LuaStandaloneEngine
.
Generally you'd set these as something like
$wgScribuntoEngineConf['luastandalone']['key'] = 'value';
- luaPath
- Specify the path to a Lua interpreter.
- errorFile
- Specify the path to a file, writable by the web server user, where the error and debugging output from the standalone interpreter will be logged.
- Error output produced by the standalone interpreter are not logged by default. Configure logging with:
$wgScribuntoEngineConf['luastandalone']['errorFile'] = '/path/to/file.log';
- memoryLimit
- Specify the memory limit in bytes. Default 52428800 (50MB) (enforced using ulimit).
- cpuLimit
- Specify the CPU time limit in seconds (enforced using ulimit).
- allowEnvFuncs
- Set true to allow use of setfenv and getfenv in modules.
LuaSandbox
editThe following keys are used in $wgScribuntoEngineConf
for Scribunto_LuaSandboxEngine
.
Generally you'd set these as something like
$wgScribuntoEngineConf['luasandbox']['key'] = 'value';
- memoryLimit
- Specify the memory limit in bytes. Default 52428800 (50MB)
- cpuLimit
- Specify the CPU time limit in seconds.
- profilerPeriod
- Specify the time between polls in sections for the Lua profiler.
- allowEnvFuncs
- Set true to allow use of setfenv and getfenv in modules.
Usage
editScripts go in a new namespace called Module. Each module has a collection of functions, which can be called using wikitext syntax such as:
{{#invoke: Module_name | function_name | arg1 | arg2 | arg3 ... }}
Lua
editLearning Lua
editLua is a simple programming language intended to be accessible to beginners. For a quick crash-course on Lua, try Learn Lua in 15 Minutes.
The best comprehensive introduction to Lua is the book Programming in Lua. The first edition (for Lua 5.0) is available online and is mostly relevant to Lua 5.1, the version used by Scribunto:
- Programming in Lua (scroll down past the book ads to find the text)
The reference manual is also useful:
Lua environment
editIn Lua, the set of all global variables and functions is called an environment.
Each {{#invoke:}}
call runs in a separate environment.
Variables defined in one {{#invoke:}}
will not be available from another.
This restriction was necessary to maintain flexibility in the wikitext parser implementation.
Debug console
edit- See also: Extension:Scribunto/Debug console
When editing a Lua module a so-called "debug console" can be found underneath the edit form. In this debug console Lua code can be executed without having to save or even create the Lua module in question.
Troubleshooting
editNote that red Script error messages are clickable and will provide more detailed information.
Lua error: Internal error: The interpreter exited with status 1.
editWhen using the LuaStandalone engine (this is the default), errors along the lines of "Lua error: Internal error: The interpreter exited with status 1." may be generated if the standalone Lua interpreter cannot be executed or runs into various runtime errors.
To obtain more information, assign a file path to $wgScribuntoEngineConf['luastandalone']['errorFile']
.
The interpreter's error output will be logged to the specified file, which should prove more helpful in tracking down the issue.
The information in the debug log includes debugging information, which is why there is so much of it.
You should be able to ignore any line beginning with "TX" or "RX".
If you're setting up Scribunto and are using IIS/Windows, this appears to be solved by commenting out a particular line.
Lua error: Internal error: The interpreter exited with status 2.
editWhen using the LuaStandalone engine (this is the default), status 2 suggests memory allocation errors, probably caused by settings that allocate inadequate memory space for PHP or Lua, or both.
Assigning a file path to $wgScribuntoEngineConf['luastandalone']['errorFile']
and examining that output can be valuable in diagnosing memory allocation errors.
Increase PHP allocation in your PHP configuration; add the line memory_limit = 200M
.
This allocation of 200MB is often sufficient (as of MediaWiki 1.24) but can be increased as required.
Set Scribunto's memory allocation in LocalSettings.php
as a line:
$wgScribuntoEngineConf['luastandalone']['memoryLimit'] = 209715200; # bytes
Finally, depending on the server configuration, some installations may be helped by adding another LocalSettings.php
line
$wgMaxShellMemory = 204800; # in KB
Note that all 3 memory limits are given in different units.
Lua error: Internal error: 2. on ARM architecture
editIf you're using an ARM architecture processor like on a RaspberryPi you'll face the error Lua error: Internal error: The interpreter exited with status 2.
due to wrong delivered binary format of the Lua interpreter.
Check your Lua interpreter in:
/path/to/webdir/Scribunto/includes/Engines/LuaStandalone/binaries/lua5_1_5_linux_32_generic
Check the interpreter by using:
file lua
The result should look like :
lua: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, for GNU/Linux 3.2.0
The installed default Lua interpreter shows:
lua: ELF 32-bit LSB pie executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.2, for GNU/Linux 2.6.9,
look at the "Intel 80386" part what definitely is not correct.
Check in /usr/bin
what version of Lua is installed on your system. If you have lua5.1 installed, you can either copy the interpreter to your lua5_1_5_linux_32_generic
directory or set in your LocalSettings.php:
$wgScribuntoEngineConf['luastandalone']['luaPath'] = '/usr/bin/lua5.1';
At present don't set wgScribuntoEngineConf
to /usr/bin/lua5.3, it'll lead to the "Internal error 1".
Lua error: Internal error: The interpreter exited with status 24.
editWhen using the LuaStandalone engine (this is the default), status 24 suggests CPU time limit errors, although those should be generating a "The time allocated for running scripts has expired" message instead. It would be useful to file a task in Phabricator and participate in determining why the XCPU signal isn't being caught.
Lua error: Internal error: The interpreter exited with status 126.
editWhen using the LuaStandalone engine (this is the default), errors along the lines of "Lua error: Internal error: The interpreter exited with status 126." may be generated if the standalone Lua interpreter cannot be executed. This generally arises from either of two causes:
- The Lua executable file's permissions do not include Execute. Set permissions as described under #Installation.
- The server does not allow execution of files from the place where the executable is installed, e.g. the filesystem is mounted with the
'noexec'
flag. This often occurs with shared hosted servers. Remedies include adjusting$wgScribuntoEngineConf['luastandalone']['luaPath']
to point to a Lua 5.1 binary installed in an executable location, or adjusting or convincing the shared host to adjust the setting preventing execution.
Error condition such as: Fatal exception of type MWException
editCheck the MediaWiki, PHP, or webserver logs for more details on the exception, or temporarily set $wgShowExceptionDetails to true
.
version 'GLIBC_2.11' not found
editIf the above gives you errors such as "version 'GLIBC_2.11' not found", it means the version of the standard C library on your system is too old for the binaries provided with Scribunto. You should upgrade your C library, or use a version of Lua 5.1 compiled for the C library you do have installed. To upgrade your C library, your best option is usually to follow your distribution's instructions for upgrading packages (or for upgrading to a new release of the distribution, if applicable).
If you copy the lua binaries from Scribunto master (or from gerrit:77905), that should suffice, if you can't or don't want to upgrade your C library. The distributed binaries were recently recompiled against an older version of glibc, so the minimum is now 2.3 rather than 2.11.
Lua errors in Scribunto files
editErrors here include:
- attempt to index field 'text' (a nil value)
- Lua error in mw.html.lua at line 253: Invalid class given:
If you are getting errors such these when attempting to use modules imported from WMF wikis, most likely your version of Scribunto is out of date.
Upgrade if possible; for advanced users, you might also try to identify the needed newer commits and cherry-pick them into your local installation.
preg_replace_callback(): Compilation failed: unknown property name after \P or \p at offset 7
editpreg_replace_callback(): Compilation failed: unknown property name after \P or \p at offset 7
- this usually indicates an incompatible version of PCRE; you'll need to update to >= 8.10
- @todo: link to instructions on how to upgrade
Lua error
editIf you copy templates from Wikipedia and then get big red "Lua error: x" messages where the Scribunto invocation (e.g. the template that uses {{#invoke:}}
) should be, that probably means that you didn't import everything you needed. Make sure that you tick the "Include templates" box at w:Special:Export when you export.
When importing pages from another wiki, it is also possible for templates or modules in the imported data to overwrite existing templates or modules with the same title, which may break existing pages, templates, and modules that depend on the overwritten versions.
Blank screen
editMake sure your extension version is applicable to your MediaWiki version.
Design documents
editOther pages
edit- Extension:Scribunto/Deployment priorities
- Extension:Scribunto/Brainstorming
- Lua scripting - Wikimedia activity page describing deployment plan to Wikimedia sites.
- Extension:Scribunto/Lua reference manual - The reference about the Lua language, as well as its standard libraries and common Scribunto modules supported on Wikimedia sites.
- Extension:Scribunto/Lua 5.2 changes - A list of known changes in Lua 5.2 that may cause code written in 5.1 to function unexpectedly.
- Extension:Scribunto/Example modules
- Extension:Scribunto/Example extension - Code for example extensions extending the Scribunto library.
- Extension:Scribunto/We use Lua
See also
edit- General
- Lua Wikibase client - functionality for the Scribunto extension.
- Commons:Lua - there may be specific notes for using Lua modules on Wikimedia Commons, including additional Lua extensions installed (e.g. for local support of internationalization and for parsing or playing medias). Some general purpose modules may be reused in other wikis in various languages (except specific tunings for policies, namespaces or project/maintenance pages with dedicated names). If possible, modules that could be widely reused across wikis should be tested and internationalized on Wikimedia Commons.
- w:Help:Lua - there may be specific notes for using Lua modules on Wikipedia, including additional Lua extensions installed (including for integrating Wikidata and Wikimedia Commons contents, generating complex infoboxes and navigation boxes, or to facilitate the general administration/maintenance of the wiki contents under applicable policies). Some other localized Wikipedia editions (or other projects such Wiktionnary, Wikisource or Wikinews) may also have their own needs and Lua modules.
- d:Help:Lua - there may be specific notes for using Lua modules on Wikidata, including additional Lua extensions installed (e.g. for local support of internationalization and for database queries)
- Extensions
- Capiunto - Provides basic infobox functionality for the Scribunto extension.
- Semantic Scribunto - provides native support for the Scribunto extension for usage with Semantic MediaWiki
- VariablesLua - provides a Scribunto Lua interface for the Variables extension
- Wikibase Client - provides Wikibase (part of Wikidata project)
External links
editNotes
edit- ↑
i.e. Scribunto will not work if
proc_open
is listed in thedisable_functions
array in your server's "php.ini" file. If it is, you may see an error message likeproc_open(): open_basedir restriction in effect. File(/dev/null) is not within the allowed path(s):
. If you are using Plesk and have been granted sufficient permissions, you may be able to setopen_basedir
in the PHP settings for your domain or subdomain. Try changing{WEBSPACEROOT}{/}{:}{TMP}{/}
to{WEBSPACEROOT}{/}{:}{TMP}{/}{:}/dev/null{:}/bin/bash
. - ↑ 2.0 2.1 2.2 The name of the engines folder changed from lowercase to capitalised in 2022.
This extension is being used on one or more Wikimedia projects. This probably means that the extension is stable and works well enough to be used by such high-traffic websites. Look for this extension's name in Wikimedia's CommonSettings.php and InitialiseSettings.php configuration files to see where it's installed. A full list of the extensions installed on a particular wiki can be seen on the wiki's Special:Version page. |
This extension is included in the following wiki farms/hosts and/or packages: This is not an authoritative list. Some wiki farms/hosts and/or packages may contain this extension even if they are not listed here. Always check with your wiki farms/hosts or bundle to confirm. |