• For best performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

• For best performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

Copy file lib/TWiki/Plugins/EmptyPlugin.pm to <name>Plugin.pm. EmptyPlugin.pm contains no executable code, so it does nothing, but it's ready to be used. Customize it. Refer to the Plugin API specs for more information.

Copy file lib/TWiki/Plugins/EmptyPlugin.pm to <name>Plugin.pm. The EmptyPlugin.pm module contains mostly empty functions, so it does nothing, but it's ready to be used. Customize it. Refer to the Plugin API specs for more information.

If your Plugin uses its own modules and objects, you must include the name of the Plugin in the package name. For example, write Package MyFirstPlugin::Attrs; instead of just Package Attrs;. Then call it using:

  use TWiki::Plugins::MyFirstPlugin::Attrs;
  $var = MyFirstPlugin::Attrs->new();

1. Copy the Plugin topic template from EmptyPlugin. To copy the text, go to the page and:
   • click Edit
   • select all in the Edit box & copy

1. Copy the Plugin topic template from TWiki.org. To copy the text, go to TWiki:Plugins/PluginPackage and:
   • enter the Plugin name in the "How to Create a Plugin" section
   • click Create
   • select all in the Edit box & copy

• • paste & save as a text file or new topic on your site

1. Customize the template for your Plugin; you'll probably want to post a working version on your local TWiki site.
2. Save your topic as a text file, for use in packaging and publishing your Plugin.

• • go back to your site to the TWiki web
  • In the GoBox enter your Plugin name, for example MyFirstPlugin, press enter and create the new topic
  • paste & save new Plugin topic on your site

1. Customize your Plugin topic.
   • In case you plan to publish your Plugin at TWiki.org, use Interwiki names for author names, like TWiki:Main/TWikiGuest.
2. Save your topic, for use in packaging and publishing your Plugin.

Check EmptyPlugin on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:

Check the Plugins web on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:

MyFirstPlugin Settings: <Description and settings for custom Plugin %VARIABLES%, and those required by TWiki.>"

Example: <Include an example of the Plugin in action. Possibly include a static HTML version of the example to compare if the installation was a success!>"

• Plugins Preferences <If user settings are needed, explain... Entering valuse works exactly like TWikiPreferences and WebPreferences: six (6) spaces and then:>"
  • Set <EXAMPLE = value added>

Plugin Global Settings: <Description and settings for custom Plugin %VARIABLES%, and those required by TWiki.>"

How-to Instructions: <Step-by-step set-up guide, user help, whatever it takes to install and run, goes here.>"

• Plugins Preferences <If user settings are needed, explain... Entering values works exactly like TWikiPreferences and WebPreferences: six (6) spaces and then:>"
  • Set <EXAMPLE = value added>

Test Example: <Include an example of the Plugin in action: if it works, the installation was a success!>"

Plugin Installation Instructions: <Step-by-step set-up guide, user help, whatever it takes to install and run, goes here.>"

-- PeterThoeny - 14 Sep 2001

-- PeterThoeny - 29 Jan 2003

The lib/TWiki/Func.pm implements ALL official Plugin functions. Plugins should ONLY use functions published in this module.

The TWikiFuncModule (lib/TWiki/Func.pm) implements ALL official Plugin functions. Plugins should ONLY use functions published in this module.

• For best performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

• For best performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

• Method 2: List the Plugin under Test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the Test web and do the testing there.

• Method 2: List the Plugin being tested in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the Sandbox web and do the testing there.

Plugins Preferences <If user settings are needed, explain... Entering valuse works exactly like TWikiPreferences and WebPreferences: six (6) spaces and then:>"

• Plugins Preferences <If user settings are needed, explain... Entering valuse works exactly like TWikiPreferences and WebPreferences: six (6) spaces and then:>"

-- MikeMannix - 01 Sep 2001

-- MikeMannix - 03 Dec 2001

• Method 1: Create Production and a Test installation of TWiki.
  • Duplicate the twiki/bin and twiki/lib directories for the Test version, adjusting the paths in the new lib/TWiki.cfg, the twiki/data; the twiki/templates and twiki/pub directories are shared.
  • Test Plugins and other new features in the Test installation until you're satisfied.
  • Copy the modified files to the Production installation. You can update a live TWiki installation and users won't even notice.

• Method 1: Safely test on-the-fly by creating separate Production and Test branches in your live TWiki installation.
  • Duplicate the twiki/bin and twiki/lib directories for the Test version, adjusting the paths in the new lib/TWiki.cfg, the twiki/data; the twiki/templates and twiki/pub directories are shared.
  • Test Plugins and other new features in the Test installation until you're satisfied.
    • If you modify topics using the new features, live users will likely see unfamiliar new META tags showing up on their pages - to avoid this, create and edit test-only topics to try out new features.
  • Copy the modified files to the Production installation. You can update a TWiki installation live and users won't even notice.

DevALERT: If you use functions not in Func.pm, you run the risk of creating security holes. Also, your Plugin will likely break and require updating when you upgrade to a new version of TWiki.

If you use functions not in Func.pm, you run the risk of creating security holes. Also, your Plugin will likely break and require updating when you upgrade to a new version of TWiki.

You can add Plugins to extend TWiki's functionality, without altering the core program code. With a plug-in approach, you can:

You can add Plugins to extend TWiki's functionality, without altering the core program code. A plug-in approach lets you:

Everything to do with TWiki Plugins - demos, new releases, downloads, development, general discussion - is available at TWiki.org, in the TWiki:Plugins web.

Everything to do with TWiki Plugins - demos, new releases, downloads, development, general discussion - is available at TWiki.org, in the TWiki:Plugins web.

• DefaultPlugin handles some legacy TWiki variables that may be present in long-established sites. This option can be controlled from TWikiPreferences. (Perl programmers can also add rules for simple custom processing.)

• DefaultPlugin optionally handles some legacy variables from older versions of TWiki. You can control this option from TWikiPreferences. (Perl programmers can also add rules for simple custom processing.)

• EmptyPlugin is a fully functional module, minus active code; it does nothing and serves as a template for new Plugin development.

• EmptyPlugin is a fully functional module, minus active code; it does nothing and serves as a template for new Plugin development.

• InterwikiPlugin is preinstalled but can be disabled or removed. Use it for quick linking to to remote sites: TWiki:Plugins expands to TWiki:Plugins on TWiki.org. You can add your own shortcuts and URLs to the existing directory of Wiki-related and other probably useful sites.

• InterwikiPlugin is preinstalled but can be disabled or removed. Use it for shorthand linking to remote sites, ex: TWiki:Plugins expands to TWiki:Plugins on TWiki.org. You can edit the predefined set of of Wiki-related sites, and add your own.

• Method 2: List the Plugin under Test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the Test web and do the testing there.

• Method 2: List the Plugin under Test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the Test web and do the testing there.

Ideally, after you've installed a Plugin, just read the instructions and you're set. In fact, some Plugins require additional settings or offer extra options that you can modify on Preferences pages. You may want to make a Plugin available only in certain webs, or temporarily disable it. And having to list all available Plugins will probably come up. You can handle all of these with simple procedures.

When you finish installing a Plugin, you should be able to read the user instructions and go. In fact, some Plugins require additional settings or offer extra options that you have to select. Also, you may want to make a Plugin available only in certain webs, or temporarily disable it. And may want to list all available Plugins in certain topics. You can handle all of these management tasks with simple procedures.

DEMO: Active Plugin Variables

DEMO: Automatically List Active Plugins Using Variables

%ACTIVATEDPLUGINS%

Using %ACTIVATEDPLUGINS%:

%PLUGINDESCRIPTIONS%

Using %PLUGINDESCRIPTIONS%:

Syntax Rules: Describe any special text formatting that will be rendered.

Syntax Rules: <Describe any special text formatting that will be rendered.>"

MyFirstPlugin Settings: Description and settings for custom Plugin %VARIABLES%, and those required by TWiki.

MyFirstPlugin Settings: <Description and settings for custom Plugin %VARIABLES%, and those required by TWiki.>"

Plugins Preferences work exactly like TWikiPreferences and WebPreferences: six (6) spaces and then:

• • Set EXAMPLE = got it!

Plugins Preferences <If user settings are needed, explain... Entering valuse works exactly like TWikiPreferences and WebPreferences: six (6) spaces and then:>"

• • Set <EXAMPLE = value added>

How-to Instructions: Step-by-step set-up guide, user help, whatever it takes to install and run, goes here.

How-to Instructions: <Step-by-step set-up guide, user help, whatever it takes to install and run, goes here.>"

Test Example: Include an example of the Plugin in action: if it works, the installation was a success!

Test Example: <Include an example of the Plugin in action: if it works, the installation was a success!>"

Plugin Info: Version, credits, history, requirements - entered in a form, displayed as a table. Both are automatically generated when you create or edit a page in the TWiki:Plugins web.

Plugin Info: <Version, credits, history, requirements - entered in a form, displayed as a table. Both are automatically generated when you create or edit a page in the TWiki:Plugins web.>"

OUTLINE: Doc Topic Contents

OUTLINE: Doc Topic Contents

-- PeterThoeny - 14 Sep 2001

-- PeterThoeny - 14 Sep 2001

Plugin use and development; about the Plugin API.

Plug-in enhanced feature add-ons, with a Plugin API for developers

You can add Plugins to greatly extend TWiki's functionality, without alering the program core. With a plug-in approach, you can:

You can add Plugins to extend TWiki's functionality, without altering the core program code. With a plug-in approach, you can:

• InterwikiPlugin is preinstalled but can be disabled or removed. Use it for quick linking to to remote sites: TWiki:Plugins expands to TWiki:Plugins on TWiki.org. You can add your own shortcuts and URLs to the existing directory of Wiki-related and other probably useful sites.

• InterwikiPlugin is preinstalled but can be disabled or removed. Use it for quick linking to to remote sites: TWiki:Plugins expands to TWiki:Plugins on TWiki.org. You can add your own shortcuts and URLs to the existing directory of Wiki-related and other probably useful sites.

Each Plugin has a standard release page, located in the TWiki:Plugins web at TWiki.org. In addition to the documentation topic (SomePlugin), there's a separate development page.

Each Plugin has a standard release page, located in the TWiki:Plugins web at TWiki.org. In addition to the documentation topic (SomePlugin), there's a separate development page.

• Dev page: Post feature requests, bug reports and general dev comments; topic title ends in Dev (SomePluginDev).

• Dev page: Post feature requests, bug reports and general dev comments; topic title ends in Dev (SomePluginDev).

• • Duplicate the twiki/bin and twiki/lib directories for the Test version, adjusting the paths in the new lib/TWiki.cfg, the twiki/data; the twiki/templates and twiki/pub directories are shared.

• • Duplicate the twiki/bin and twiki/lib directories for the Test version, adjusting the paths in the new lib/TWiki.cfg, the twiki/data; the twiki/templates and twiki/pub directories are shared.

• Method 2: List the Plugin under Test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the Test web and do the testing there.

• Method 2: List the Plugin under Test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the Test web and do the testing there.

• All Plugin modules present in the lib/TWiki/Plugins directory are activated automatically unless disabled by the DISABLEDPLUGINS Preferences variable in TWikiPreferences. You can optionally list the installed Plugins in the INSTALLEDPLUGINS Preferences variable. This is useful to define the sequence of Plugin execution, or to specify other webs than the TWiki web for the Plugin topics. Settings in TWikiPreferences are:
  • Set INSTALLEDPLUGINS = DefaultPlugin, ...
  • Set DISABLEDPLUGINS = EmptyPlugin, ...

• All Plugin modules present in the lib/TWiki/Plugins directory are activated automatically unless disabled by the DISABLEDPLUGINS Preferences variable in TWikiPreferences. You can optionally list the installed Plugins in the INSTALLEDPLUGINS Preferences variable. This is useful to define the sequence of Plugin execution, or to specify other webs than the TWiki web for the Plugin topics. Settings in TWikiPreferences are:
  • Set INSTALLEDPLUGINS = DefaultPlugin, ...
  • Set DISABLEDPLUGINS = EmptyPlugin, ...

Plugin execution order in TWiki is determined by searching Plugin topics in a specific sequence: First, full web.topicname name, if specified in INSTALLEDPLUGINS; next, the TWiki web is searched; and finally, the current web.

Plugin execution order in TWiki is determined by searching Plugin topics in a specific sequence: First, full web.topicname name, if specified in INSTALLEDPLUGINS; next, the TWiki web is searched; and finally, the current web.

• • Set SHORTDESCRIPTION = Blah blah woof woof.

1. Debug Plugin, output can be seen in data/debug.txt. Set to 0=off or 1=on:
   • Set DEBUG = 0

• The settings can be retrieved as Preferences variables like %<pluginname>_<var>%, ex: %DEFAULTPLUGIN_SHORTDESCRIPTION% shows the description of the DefaultPlugin.

• • Set SHORTDESCRIPTION = Blah blah woof woof.

1. Debug Plugin, output can be seen in data/debug.txt. Set to 0=off or 1=on:
   • Set DEBUG = 0

• The settings can be retrieved as Preferences variables like %<pluginname>_<var>%, ex: %DEFAULTPLUGIN_SHORTDESCRIPTION% shows the description of the DefaultPlugin.

• The %ACTIVATEDPLUGINS% variable lists activated Plugins by name. (This variable is displayed in TWikiPreferences for debugging use.)
• The %PLUGINDESCRIPTIONS% variable displays a bullet list with a one-line description of each active Plugins. This variable is based on the %<plugin>_SHORTDESCRIPTION% Preferences variables of individual topics and is shown in TextFormattingRules.

• The %ACTIVATEDPLUGINS% variable lists activated Plugins by name. (This variable is displayed in TWikiPreferences for debugging use.)
• The %PLUGINDESCRIPTIONS% variable displays a bullet list with a one-line description of each active Plugins. This variable is based on the %<plugin>_SHORTDESCRIPTION% Preferences variables of individual topics and is shown in TextFormattingRules.

%ACTIVATEDPLUGINS%

%ACTIVATEDPLUGINS%

%PLUGINDESCRIPTIONS%

%PLUGINDESCRIPTIONS%

The lib/TWiki/Func.pm implements ALL official Plugin functions. Plugins should ONLY use functions published in this module.

The lib/TWiki/Func.pm implements ALL official Plugin functions. Plugins should ONLY use functions published in this module.

DevALERT: If you use functions not in Func.pm, you run the risk of creating security holes. Also, your Plugin will likely break and require updating when you upgrade to a new version of TWiki.

DevALERT: If you use functions not in Func.pm, you run the risk of creating security holes. Also, your Plugin will likely break and require updating when you upgrade to a new version of TWiki.

• For best performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

• For best performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

In addition to TWiki core functions, Plugins can use predefined hooks, or call backs, listed in the lib/TWiki/Plugins/EmptyPlugin.pm module.

In addition to TWiki core functions, Plugins can use predefined hooks, or call backs, listed in the lib/TWiki/Plugins/EmptyPlugin.pm module.

• All but the initPlugin are disabled. To enable a call back, remove DISABLE_ from the function name.

• All but the initPlugin are disabled. To enable a call back, remove DISABLE_ from the function name.

To eliminate the incompatibility problems bound to arise from active open Plugin development, a Plugin versioning system and an API GetVersion detection routine are provided for automatic compatibility checking.

To eliminate the incompatibility problems bound to arise from active open Plugin development, a Plugin versioning system and an API GetVersion detection routine are provided for automatic compatibility checking.

• All modules require a $VERSION='0.000' variable, beginning at 1.000.

• All modules require a $VERSION='0.000' variable, beginning at 1.000.

• The initPlugin handler should check all dependencies and return TRUE if the initialization is OK or FALSE if something went wrong.
  • The Plugin initialization code does not register a Plugin that returns FALSE (or that has no initPlugin handler).

• The initPlugin handler should check all dependencies and return TRUE if the initialization is OK or FALSE if something went wrong.
  • The Plugin initialization code does not register a Plugin that returns FALSE (or that has no initPlugin handler).

• $VERSION='1.000' is the current setting in TWiki::Plugins.pm and in the preinstalled system Plugins (DefaultPlugin, EmptyPlugin, InterwikiPlugin).

• $VERSION='1.000' is the current setting in TWiki::Plugins.pm and in the preinstalled system Plugins (DefaultPlugin, EmptyPlugin, InterwikiPlugin).

• a Perl module, ex: MyFirstPlugin.pm
• a documentation topic, ex: MyFirstPlugin.txt

• a Perl module, ex: MyFirstPlugin.pm
• a documentation topic, ex: MyFirstPlugin.txt

In particular, files that should be web-accessible (graphics, Java applets ...) are best placed as attachments of the MyFirstPlugin topic. Other needed Perl code is best placed in a lib/TWiki/Plugins/MyFirstPlugin/ directory.

In particular, files that should be web-accessible (graphics, Java applets ...) are best placed as attachments of the MyFirstPlugin topic. Other needed Perl code is best placed in a lib/TWiki/Plugins/MyFirstPlugin/ directory.

Copy file lib/TWiki/Plugins/EmptyPlugin.pm to <name>Plugin.pm. EmptyPlugin.pm contains no executable code, so it does nothing, but it's ready to be used. Customize it. Refer to the Plugin API specs for more information.

Copy file lib/TWiki/Plugins/EmptyPlugin.pm to <name>Plugin.pm. EmptyPlugin.pm contains no executable code, so it does nothing, but it's ready to be used. Customize it. Refer to the Plugin API specs for more information.

A minimum Plugin release consists of a Perl module with a WikiName that ends in Plugin, ex: MyFirstPlugin.pm, and a documentation page with the same name(MyFirstPlugin.txt).

A minimum Plugin release consists of a Perl module with a WikiName that ends in Plugin, ex: MyFirstPlugin.pm, and a documentation page with the same name(MyFirstPlugin.txt).

• • lib/TWiki/Plugins/MyFirstPlugin.pm
  • data/TWiki/MyFirstPlugin.txt
  • pub/TWiki/MyFirstPlugin/uparrow.gif [a required graphic]

1. Create a zip archive with the Plugin name (MyFirstPlugin.zip) and add the entire directory structure from Step 1. The archive should look like this:
   • lib/TWiki/Plugins/MyFirstPlugin.pm
   • data/TWiki/MyFirstPlugin.txt
   • pub/TWiki/MyFirstPlugin/uparrow.gif

• • lib/TWiki/Plugins/MyFirstPlugin.pm
  • data/TWiki/MyFirstPlugin.txt
  • pub/TWiki/MyFirstPlugin/uparrow.gif [a required graphic]

1. Create a zip archive with the Plugin name (MyFirstPlugin.zip) and add the entire directory structure from Step 1. The archive should look like this:
   • lib/TWiki/Plugins/MyFirstPlugin.pm
   • data/TWiki/MyFirstPlugin.txt
   • pub/TWiki/MyFirstPlugin/uparrow.gif

You can release your tested, packaged Plugin to the TWiki community through the TWiki:Plugins web, where all Plugins submitted to TWiki.org are available for download and further development discussion. Publish your Plugin in three steps:

You can release your tested, packaged Plugin to the TWiki community through the TWiki:Plugins web. All Plugins submitted to TWiki.org are available for download and further development in TWiki:Plugins. Publish your Plugin in three steps:

• • create a new topic using the Plugin name, ex: MyFirstPlugin.txt;
  • paste in the topic text from Creating Plugin Documentation and Save.

1. Attach the distribution zip file to the topic, ex: MyFirstPlugin.zip.
2. Link from the doc page to a new, blank page named after the Plugin, and ending in Dev, ex: MyFirstPluginDev. This is the discussion page for future development. (User support for Plugins is handled in TWiki:Support.)

• • create a new topic using the Plugin name, ex: MyFirstPlugin.txt
  • paste in the topic text from Creating Plugin Documentation and save

1. Attach the distribution zip file to the topic, ex: MyFirstPlugin.zip
2. Link from the doc page to a new, blank page named after the Plugin, and ending in Dev, ex: MyFirstPluginDev. This is the discussion page for future development. (User support for Plugins is handled in TWiki:Support.)

Everything to do with TWiki Plugins - demos, new releases, downloads, development, general discussion - is available at TWiki.org, in the TWiki.org Plugins web.

Everything to do with TWiki Plugins - demos, new releases, downloads, development, general discussion - is available at TWiki.org, in the TWiki:Plugins web.

• EmptyPlug is a fully functional module, minus active code; it does nothing and serves as a template for new Plugin development.

• EmptyPlugin is a fully functional module, minus active code; it does nothing and serves as a template for new Plugin development.

%ACTIVATEDPLUGINS%

%ACTIVATEDPLUGINS%

%PLUGINDESCRIPTIONS%

%PLUGINDESCRIPTIONS%

The Application Programming Interface (API) for TWikiPlugins provides the specifications for hooking into the core TWiki code from your external Perl Plugin module. The Plugin API is new to the Production version of TWiki with the TWikiReleaseSpring2001.

The Application Programming Interface (API) for TWikiPlugins provides the specifications for hooking into the core TWiki code from your external Perl Plugin module. The Plugin API is new to the Production version of TWiki with the 01-Sep-2001 release.

• DefaultPlugin can handle some outdated TWiki variables, found, for example, in sites recently updated from an old version. Settings are in TWikiPreferences. You can also add your own simple custom processing rules here, though in all but very simple cases, writing a new Plugin is preferable.

• DefaultPlugin can handle some outdated TWiki variables, found, for example, in sites recently updated from an old version. Settings are in DefaultPlugin topic. You can also add your own simple custom processing rules here, though in all but very simple cases, writing a new Plugin is preferable.

• a Perl module, ex: YourPlugin.pm
• a documentation topic, ex: YourPlugin.txt

• a Perl module, ex: MyFirstPlugin.pm
• a documentation topic, ex: MyFirstPlugin.txt

In particular, files that should be web-accessible (graphics, Java applets ...) are best placed as attachments of the YourPlugin topic. Other needed Perl code is best placed in a lib/TWiki/Plugins/YourPlugin/ directory.

In particular, files that should be web-accessible (graphics, Java applets ...) are best placed as attachments of the MyFirstPlugin topic. Other needed Perl code is best placed in a lib/TWiki/Plugins/MyFirstPlugin/ directory.

Copy file (EmptyPlugin.pm to <name>Plugin.pm =EmptyPlugin.pm= contains no executable code, so it does nothing, but it's ready to be used. Customize it. Refer to the Plugin API specs for more information.

Copy file lib/TWiki/Plugins/EmptyPlugin.pm to <name>Plugin.pm. EmptyPlugin.pm contains no executable code, so it does nothing, but it's ready to be used. Customize it. Refer to the Plugin API specs for more information.

1. Copy the Plugin topic template from http://TWiki.org/cgi-bin/view/TWiki/EmptyPlugin. To copy the text, go to the page and:

1. Copy the Plugin topic template from EmptyPlugin. To copy the text, go to the page and:

Check EmptyPlugin on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:

Check EmptyPlugin on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:

YourPlugin Settings: Description and settings for your custom Plugin %VARIABLES%, and those required by TWiki.

MyFirstPlugin Settings: Description and settings for custom Plugin %VARIABLES%, and those required by TWiki.

A minimum Plugin release consists of a Perl module with a WikiName that ends in Plugin, ex: YourPlugin.pm, and a documentation page with the same name(YourPlugin.txt).

A minimum Plugin release consists of a Perl module with a WikiName that ends in Plugin, ex: MyFirstPlugin.pm, and a documentation page with the same name(MyFirstPlugin.txt).

1. Distribute your Plugin files in a directory structure that mirrors TWiki. If your Plugin uses additional files, include them ALL:
   • lib/TWiki/Plugins/YourPlugin.pm
   • data/TWiki/YourPlugin.txt
   • pub/TWiki/YourPlugin/uparrow.gif [a required graphic]
2. Create a zip archive with the Plugin name (YourPlugin.zip) and add the entire directory structure from Step 1. Your archive should look like this:
   • lib/TWiki/Plugins/YourPlugin.pm
   • data/TWiki/YourPlugin.txt
   • pub/TWiki/YourPlugin/uparrow.gif

1. Distribute the Plugin files in a directory structure that mirrors TWiki. If your Plugin uses additional files, include them ALL:
   • lib/TWiki/Plugins/MyFirstPlugin.pm
   • data/TWiki/MyFirstPlugin.txt
   • pub/TWiki/MyFirstPlugin/uparrow.gif [a required graphic]
2. Create a zip archive with the Plugin name (MyFirstPlugin.zip) and add the entire directory structure from Step 1. The archive should look like this:
   • lib/TWiki/Plugins/MyFirstPlugin.pm
   • data/TWiki/MyFirstPlugin.txt
   • pub/TWiki/MyFirstPlugin/uparrow.gif

• • create a new topic using the Plugin name, ex: YourPlugin.txt;

• • create a new topic using the Plugin name, ex: MyFirstPlugin.txt;

1. Attach the distribution zip file to the topic, ex: YourPlugin.zip.
2. Link from the doc page to a new, blank page named after the Plugin, and ending in Dev, ex: YourPluginDev. This is the discussion page for future development. (User support for Plugins is handled in TWiki:Support.)

1. Attach the distribution zip file to the topic, ex: MyFirstPlugin.zip.
2. Link from the doc page to a new, blank page named after the Plugin, and ending in Dev, ex: MyFirstPluginDev. This is the discussion page for future development. (User support for Plugins is handled in TWiki:Support.)

-- AndreaSterbini - 29 May 2001
-- MikeMannix - 01 Sep 2001

-- AndreaSterbini - 29 May 2001
-- MikeMannix - 01 Sep 2001
-- PeterThoeny - 14 Sep 2001

TWiki Plugins

TWiki Plugins

Overview

Overview

Preinstalled Plugins

Preinstalled Plugins

Installing Plugins

Installing Plugins

On-Site Pretesting

On-Site Pretesting

Managing Plugins

Managing Plugins

Setting Preferences

Setting Preferences

Listing Active Plugins

Listing Active Plugins

The TWiki Plugin API

The TWiki Plugin API

Available Core Functions

Available Core Functions

Predefined Hooks

Predefined Hooks

Plugin Version Detection

Plugin Version Detection

Creating Plugins

Creating Plugins

The DefaultPlugin Alternative

The DefaultPlugin Alternative

Anatomy of a Plugin

Anatomy of a Plugin

Creating the Perl Module

Creating the Perl Module

Writing the Documentation Topic

Writing the Documentation Topic

Packaging for Distribution

Packaging for Distribution

Publishing for Public Use

Publishing for Public Use

• The initPlugin handler checks all dependencies and returns TRUE if the initialization is OK or FALSE if something went wrong.

• The initPlugin handler should check all dependencies and return TRUE if the initialization is OK or FALSE if something went wrong.

In particular, files that should be web-accessible (graphics, Java applets ...) are best placed as attachments of the YourPlugin topic. Other needed Perl code is best placed in a lib/TWiki/Plugins/YourPlugin/ directory.

TWikiPlugins allow you to add new features to TWiki without changing the core program. Using a plug-in approach means that you can:

Plugin use and development; about the Plugin API.

• add virtually unlimited features while keeping the main TWiki program compact and efficient;

Overview

You can add Plugins to greatly extend TWiki's functionality, without alering the program core. With a plug-in approach, you can:

• add virtually unlimited features while keeping the main TWiki code compact and efficient;

Everything to do with TWiki Plugins - including demos, new releases, downloads, and discussion - is available at TWiki.org, in the TWiki.org Plugins web.

Everything to do with TWiki Plugins - demos, new releases, downloads, development, general discussion - is available at TWiki.org, in the TWiki.org Plugins web.

Preinstalled Plugins

TWiki comes with three Plugins as part of the standard installation.

• DefaultPlugin handles some legacy TWiki variables that may be present in long-established sites. This option can be controlled from TWikiPreferences. (Perl programmers can also add rules for simple custom processing.)

• EmptyPlug is a fully functional module, minus active code; it does nothing and serves as a template for new Plugin development.

• InterwikiPlugin is preinstalled but can be disabled or removed. Use it for quick linking to to remote sites: TWiki:Plugins expands to TWiki:Plugins on TWiki.org. You can add your own shortcuts and URLs to the existing directory of Wiki-related and other probably useful sites.

Some Plugins need certain Perl modules to be pre-installed on the host system. Plugins may also use other resources, like graphics, other modules, applications, templates. In these cases, detailed instructions are in the Plugin documentation.

Special Requests: Some Plugins need certain Perl modules to be preinstalled on the host system. Plugins may also use other resources, like graphics, other modules, applications, templates. In these cases, detailed instructions are in the Plugin documentation.

TWikiPlugin documentation pages are located at TWiki.org, in TWiki:Plugins web. Each Plugin has an doc topic (ex: SomePlugin) and a separate development page.

Each Plugin has a standard release page, located in the TWiki:Plugins web at TWiki.org. In addition to the documentation topic (SomePlugin), there's a separate development page.

• Dev page: Post feature requests, bug reports and general dev comments; topic title ends in Dev (ex: SomePluginDev).

• Dev page: Post feature requests, bug reports and general dev comments; topic title ends in Dev (SomePluginDev).

Preinstalled Plugins

On-Site Pretesting

TWiki comes with three Plugins as part of the standard installation.

To test new Plugins on your installation before making them public, you may want to use one of these two approaches:

• DefaultPlugin handles some legacy TWiki variables that may be present in long-established sites. This option can be controlled from TWikiPreferences. (Perl programmers can also add rules for simple custom processing.)

• Method 1: Create Production and a Test installation of TWiki.
  • Duplicate the twiki/bin and twiki/lib directories for the Test version, adjusting the paths in the new lib/TWiki.cfg, the twiki/data; the twiki/templates and twiki/pub directories are shared.
  • Test Plugins and other new features in the Test installation until you're satisfied.
  • Copy the modified files to the Production installation. You can update a live TWiki installation and users won't even notice.

• EmptyPlug is a fully functional Plugin module, minus any active code; it does nothing but serve as a template on demand.

• Method 2: List the Plugin under Test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the Test web and do the testing there.

• InterwikiPlugin is included but can be disabled or removed. Use it for quick linking to frequently linked to remote sites. Ex: TWiki:Plugins expands to TWiki:Plugins - on TWiki.org. You can add your own shortcuts and URLs to the existing directory of Wiki-related sites.

TIP! To test new Plugins on your installation before making them public, you may want to use one of these two approaches:

The TWiki Plugin API

• Method 1: Create a Production and a Test installation of TWiki. The twiki/data, twiki/templates and twiki/pub directories are shared, and the twiki/bin and twiki/lib directories are separate. Do all tests of Plugins and other new features in the Test installation. When everything works, copy the modified files over to the Production installation. This way, you can update a live TWiki installation and users won't even notice.

The Application Programming Interface (API) for TWikiPlugins provides the specifications for hooking into the core TWiki code from your external Perl Plugin module. The Plugin API is new to the Production version of TWiki with the TWikiReleaseSpring2001.

• Method 2: List the Plugin under test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the test web and do the testing there.

Available Core Functions

Creating Plugins

The lib/TWiki/Func.pm implements ALL official Plugin functions. Plugins should ONLY use functions published in this module.

With a reasonable knowledge of the Perl scripting language, you can create new Plugins or modify and extend existing ones. Basic plug-in architecture uses an Application Programming Interface (API), a set of software instructions that allow external code to interact with the main program. The TWiki Plugin API Plugins by providing a programming interface for TWiki.

DevALERT: If you use functions not in Func.pm, you run the risk of creating security holes. Also, your Plugin will likely break and require updating when you upgrade to a new version of TWiki.

Anatomy of a Plugin

• For best performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

A basic TWiki Plugin consists of two elements:

Predefined Hooks

• a Perl module, ex: YourPlugin.pm
• a documentation topic, ex: YourPlugin.txt

In addition to TWiki core functions, Plugins can use predefined hooks, or call backs, listed in the lib/TWiki/Plugins/EmptyPlugin.pm module.

The Perl module can be a block of code that connects with TWiki alone, or it can include other elements, like other Perl modules (including other Plugins), graphics, TWiki templates, external applications (ex: a Java applet), or just about anything else it can call.

• All but the initPlugin are disabled. To enable a call back, remove DISABLE_ from the function name.

The Plugin API handles the details of connecting your Perl module with main TWiki code. When you're familiar with the Plugin API, you're ready to develop Plugins.

Plugin Version Detection

TWiki Plugin API

To eliminate the incompatibility problems bound to arise from active open Plugin development, a Plugin versioning system and an API GetVersion detection routine are provided for automatic compatibility checking.

The Application Programming Interface (API) for TWikiPlugins provides the specifications for hooking into the core TWiki code from your external Perl Plugin module. The Plugin API is new to the Production version of TWiki with the TWikiReleaseSpring2001.

• All modules require a $VERSION='0.000' variable, beginning at 1.000.

The lib/TWiki/Func.pm implements ALL official Plugin functions. Plugins should ONLY use functions published in this module.

• The initPlugin handler checks all dependencies and returns TRUE if the initialization is OK or FALSE if something went wrong.
  • The Plugin initialization code does not register a Plugin that returns FALSE (or that has no initPlugin handler).

DevALERT: If you use functions not in Func.pm, you run the risk of creating security holes. Also, your Plugin will likely break and require updating when you upgrade to a new version of TWiki.

• $VERSION='1.000' is the current setting in TWiki::Plugins.pm and in the preinstalled system Plugins (DefaultPlugin, EmptyPlugin, InterwikiPlugin).

In addition to TWiki core functions, Plugins can use predefined hooks, or call backs, listed in the lib/TWiki/Plugins/EmptyPlugin.pm module.

• All but the initPlugin are disabled. To enable a call back, remove DISABLE_ from the function name.

Creating Plugins

• For improve performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

With a reasonable knowledge of the Perl scripting language, you can create new Plugins or modify and extend existing ones. Basic plug-in architecture uses an Application Programming Interface (API), a set of software instructions that allow external code to interact with the main program. The TWiki Plugin API Plugins by providing a programming interface for TWiki.

Anatomy of a Plugin

A basic TWiki Plugin consists of two elements:

• a Perl module, ex: YourPlugin.pm
• a documentation topic, ex: YourPlugin.txt

The Perl module can be a block of code that connects with TWiki alone, or it can include other elements, like other Perl modules (including other Plugins), graphics, TWiki templates, external applications (ex: a Java applet), or just about anything else it can call.

The Plugin API handles the details of connecting your Perl module with main TWiki code. When you're familiar with the Plugin API, you're ready to develop Plugins.

-- MikeMannix - 26 Aug 2001

-- AndreaSterbini - 29 May 2001
-- MikeMannix - 01 Sep 2001

Pre-Installed Plugins

Preinstalled Plugins

Managing Installed Plugins

Managing Plugins

Set Preferences for Individual Plugins

Setting Preferences

List Active Plugins Automatically

Listing Active Plugins

Creating New Plugins

Creating Plugins

Customize the DefaultPlugin

The DefaultPlugin Alternative

Create a Plugin Module in Perl

Creating the Perl Module

Create a Plugin Documentation Topic

Writing the Documentation Topic

Package a Plugin for Distribution

Packaging for Distribution

Publish a Plugin for General Use

Publishing for Public Use

About Plugins

Everything to do with TWiki Plugins - including demos, new releases, downloads, and discussion - is available at TWiki.org, in the TWiki.org Plugins web.

Everything to do with TWiki Plugins - including demos, new releases, downloads, and discussion - is available at TWiki.org, in the TWiki.org Plugins web.

Installed Plugins can be toggled on or off, site-wide or by web, through TWikiPreferences and individual WebPreferences:

Installed Plugins can be toggled on or off, site-wide or by web, through TWikiPreferences and individual WebPreferences:

• All Plugin modules present in the lib/TWiki/Plugins directory are activated automatically unless disabled by the DISABLEDPLUGINS Preferences variable in TWikiPreferences. You can optionally list the installed Plugins in the INSTALLEDPLUGINS Preferences variable. This is useful to define the sequence of Plugin execution, or to specify other webs than the TWiki web for the Plugin topics. Settings in TWikiPreferences are:

• All Plugin modules present in the lib/TWiki/Plugins directory are activated automatically unless disabled by the DISABLEDPLUGINS Preferences variable in TWikiPreferences. You can optionally list the installed Plugins in the INSTALLEDPLUGINS Preferences variable. This is useful to define the sequence of Plugin execution, or to specify other webs than the TWiki web for the Plugin topics. Settings in TWikiPreferences are:

• The %ACTIVATEDPLUGINS% variable lists activated Plugins by name. (This variable is displayed in TWikiPreferences for debugging use.)
• The %PLUGINDESCRIPTIONS% variable displays a bullet list with a one-line description of each active Plugins. This variable is based on the %<plugin>_SHORTDESCRIPTION% Preferences variables of individual topics and is shown in TextFormattingRules.

• The %ACTIVATEDPLUGINS% variable lists activated Plugins by name. (This variable is displayed in TWikiPreferences for debugging use.)
• The %PLUGINDESCRIPTIONS% variable displays a bullet list with a one-line description of each active Plugins. This variable is based on the %<plugin>_SHORTDESCRIPTION% Preferences variables of individual topics and is shown in TextFormattingRules.

• Method 2: List the Plugin under test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the test web and do the testing there.

• Method 2: List the Plugin under test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the test web and do the testing there.

Check EmptyPlugin on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:

Check EmptyPlugin on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:

Syntax Rules: explanation coming up

Syntax Rules: Describe any special text formatting that will be rendered.

• • paste in the topic text from How to Create the Plugin Documentation Topic and Save.

• • paste in the topic text from Creating Plugin Documentation and Save.

-- MikeMannix - 26 Aug 2001

-- MikeMannix - 26 Aug 2001

TWiki Plugins

• TWiki Plugins

TWiki Plugins

Plugins allow you to extend the syntax or functionality of TWiki. ...

About Plugins

TWikiPreferences has the list of installed plugins and activated plugins.

TWikiPlugins allow you to add new features to TWiki without changing the core program. Using a plug-in approach means that you can:

How to Create a Plugin

• add virtually unlimited features while keeping the main TWiki program compact and efficient;
• heavily customize an installation and still do clean updates to new versions of TWiki;
• rapidly develop new TWiki functions in Perl using the Plugin API.

under construction... ( check back at http://TWiki.org/cgi-bin/view/TWiki/TWikiPlugins )

Everything to do with TWiki Plugins - including demos, new releases, downloads, and discussion - is available at TWiki.org, in the TWiki.org Plugins web.

How to Install a Plugin

Installing Plugins

under construction... ( check back at http://TWiki.org/cgi-bin/view/TWiki/TWikiPlugins )

Each TWikiPlugin comes with full documentation: step-by-step installation instructions, a detailed description of any special requirements, version details, and a working example for testing.

Plugins under the hood

Most Plugins can be installed in three easy steps, with no programming skills required:

1. Download the zip file containing the Plugin, documentation, and any other required files, from TWiki:Plugins.
2. Distribute the files to their proper locations - unzip the zip archive in your TWiki installation directory - if have a standard TWiki installation, this will distribute automatically. Otherwise, place the files according to the directory paths listed on the Plugin top in TWiki:Plugins.
3. Check the demo example on the Plugin topic: if it's working, the installation was fine!

• All plugin modules that exist in the lib/TWiki/Plugins directory are activated automatically unless disabled by the DISABLEDPLUGINS preferences variable in TWikiPreferences. You can optionally list the installed plugins in the INSTALLEDPLUGINS preferences variable. This is useful to define the sequence of plugin execution, or to specify other webs then the TWiki web for the plugin topics. Settings in TWikiPreferences:
  • Set INSTALLEDPLUGINS = DefaultPlugin, ...
  • Set DISABLEDPLUGINS = EmptyPlugin, ...

Some Plugins need certain Perl modules to be pre-installed on the host system. Plugins may also use other resources, like graphics, other modules, applications, templates. In these cases, detailed instructions are in the Plugin documentation.

• The %ACTIVATEDPLUGINS% variable shows all currently activated plugins. This variable is shown in TWikiPreferences for debug reasons.

TWikiPlugin documentation pages are located at TWiki.org, in TWiki:Plugins web. Each Plugin has an doc topic (ex: SomePlugin) and a separate development page.

• Doc page: Read all available info about the Plugin; download the attached distribution files.
• Dev page: Post feature requests, bug reports and general dev comments; topic title ends in Dev (ex: SomePluginDev).
• User support: Post installation, how to use type questions (and answers, if you have them) in the TWiki:Support web.

• Search order for plugin topics: Full web.topicname name is used if specified in INSTALLEDPLUGINS, then the TWiki web is searched, then the current web.

Pre-Installed Plugins

• Plugin specific settings are done in individual plugin topics. Two settings are standard for each plugin:
  • One line description, used to form the bullets describing the plugins in the TextFormattingRules topic:
    • Set SHORTDESCRIPTION = Blah blah.
  • Debug plugin, output can be seen in data/debug.txt: (Se to 0 or 1)
    • Set DEBUG = 0
  • The settings can be retrieved as preferences variables like %<pluginname>_<var>%, i.e. %DEFAULTPLUGIN_SHORTDESCRIPTION% shows the description of the DefaultPlugin.

TWiki comes with three Plugins as part of the standard installation.

• The %PLUGINDESCRIPTIONS% variable shows a bullet list with descriptions of all currently activated plugins. This variable is based on %<plugin>_SHORTDESCRIPTION% preferences variables of individual topics and is shown in TextFormattingRules.

• DefaultPlugin handles some legacy TWiki variables that may be present in long-established sites. This option can be controlled from TWikiPreferences. (Perl programmers can also add rules for simple custom processing.)

-- PeterThoeny - 14 Jul 2001

• EmptyPlug is a fully functional Plugin module, minus any active code; it does nothing but serve as a template on demand.

• InterwikiPlugin is included but can be disabled or removed. Use it for quick linking to frequently linked to remote sites. Ex: TWiki:Plugins expands to TWiki:Plugins - on TWiki.org. You can add your own shortcuts and URLs to the existing directory of Wiki-related sites.

Managing Installed Plugins

Ideally, after you've installed a Plugin, just read the instructions and you're set. In fact, some Plugins require additional settings or offer extra options that you can modify on Preferences pages. You may want to make a Plugin available only in certain webs, or temporarily disable it. And having to list all available Plugins will probably come up. You can handle all of these with simple procedures.

Set Preferences for Individual Plugins

Installed Plugins can be toggled on or off, site-wide or by web, through TWikiPreferences and individual WebPreferences:

• All Plugin modules present in the lib/TWiki/Plugins directory are activated automatically unless disabled by the DISABLEDPLUGINS Preferences variable in TWikiPreferences. You can optionally list the installed Plugins in the INSTALLEDPLUGINS Preferences variable. This is useful to define the sequence of Plugin execution, or to specify other webs than the TWiki web for the Plugin topics. Settings in TWikiPreferences are:
  • Set INSTALLEDPLUGINS = DefaultPlugin, ...
  • Set DISABLEDPLUGINS = EmptyPlugin, ...

Plugin execution order in TWiki is determined by searching Plugin topics in a specific sequence: First, full web.topicname name, if specified in INSTALLEDPLUGINS; next, the TWiki web is searched; and finally, the current web.

Plugin-specific settings are done in individual Plugin topics. Two settings are standard for each Plugin:

1. One line description, used to form the bullets describing the Plugins in the TextFormattingRules topic:
   • Set SHORTDESCRIPTION = Blah blah woof woof.
2. Debug Plugin, output can be seen in data/debug.txt. Set to 0=off or 1=on:
   • Set DEBUG = 0

• The settings can be retrieved as Preferences variables like %<pluginname>_<var>%, ex: %DEFAULTPLUGIN_SHORTDESCRIPTION% shows the description of the DefaultPlugin.

List Active Plugins Automatically

Plugin status variables let you list all active Plugins wherever needed. There are two list formats:

• The %ACTIVATEDPLUGINS% variable lists activated Plugins by name. (This variable is displayed in TWikiPreferences for debugging use.)
• The %PLUGINDESCRIPTIONS% variable displays a bullet list with a one-line description of each active Plugins. This variable is based on the %<plugin>_SHORTDESCRIPTION% Preferences variables of individual topics and is shown in TextFormattingRules.

DEMO: Active Plugin Variables

%ACTIVATEDPLUGINS%
On this TWiki site, the active Plugins are: DefaultPlugin, InterwikiPlugin.

%PLUGINDESCRIPTIONS%
You can use any of these active TWiki Plugins:

• DefaultPlugin: This plugin can be used to specify some simple custom rendering rules. It also renders deprecated *_text_* as bold italic text.
• InterwikiPlugin: Link ExternalSite:Page text to external sites based on aliases defined in the InterWikis topic.

TIP! To test new Plugins on your installation before making them public, you may want to use one of these two approaches:

• Method 1: Create a Production and a Test installation of TWiki. The twiki/data, twiki/templates and twiki/pub directories are shared, and the twiki/bin and twiki/lib directories are separate. Do all tests of Plugins and other new features in the Test installation. When everything works, copy the modified files over to the Production installation. This way, you can update a live TWiki installation and users won't even notice.

• Method 2: List the Plugin under test in the DISABLEDPLUGINS variable in TWikiPreferences. Redefine the DISABLEDPLUGINS variable in the test web and do the testing there.

Creating New Plugins

With a reasonable knowledge of the Perl scripting language, you can create new Plugins or modify and extend existing ones. Basic plug-in architecture uses an Application Programming Interface (API), a set of software instructions that allow external code to interact with the main program. The TWiki Plugin API Plugins by providing a programming interface for TWiki.

Anatomy of a Plugin

A basic TWiki Plugin consists of two elements:

• a Perl module, ex: YourPlugin.pm
• a documentation topic, ex: YourPlugin.txt

The Perl module can be a block of code that connects with TWiki alone, or it can include other elements, like other Perl modules (including other Plugins), graphics, TWiki templates, external applications (ex: a Java applet), or just about anything else it can call.

The Plugin API handles the details of connecting your Perl module with main TWiki code. When you're familiar with the Plugin API, you're ready to develop Plugins.

TWiki Plugin API

The Application Programming Interface (API) for TWikiPlugins provides the specifications for hooking into the core TWiki code from your external Perl Plugin module. The Plugin API is new to the Production version of TWiki with the TWikiReleaseSpring2001.

The lib/TWiki/Func.pm implements ALL official Plugin functions. Plugins should ONLY use functions published in this module.

DevALERT: If you use functions not in Func.pm, you run the risk of creating security holes. Also, your Plugin will likely break and require updating when you upgrade to a new version of TWiki.

In addition to TWiki core functions, Plugins can use predefined hooks, or call backs, listed in the lib/TWiki/Plugins/EmptyPlugin.pm module.

• All but the initPlugin are disabled. To enable a call back, remove DISABLE_ from the function name.

• For improve performance, enable only the functions you really need. NOTE: outsidePREHandler and insidePREHandler are particularly expensive.

Customize the DefaultPlugin

• DefaultPlugin can handle some outdated TWiki variables, found, for example, in sites recently updated from an old version. Settings are in TWikiPreferences. You can also add your own simple custom processing rules here, though in all but very simple cases, writing a new Plugin is preferable.

Create a Plugin Module in Perl

Copy file (EmptyPlugin.pm to <name>Plugin.pm =EmptyPlugin.pm= contains no executable code, so it does nothing, but it's ready to be used. Customize it. Refer to the Plugin API specs for more information.

Create a Plugin Documentation Topic

The Plugin documentation topic contains usage instructions and version details. It serves the Plugin files as FileAttachments for downloading. (The doc topic is also included in the distribution package.) To create a documentation topic:

1. Copy the Plugin topic template from http://TWiki.org/cgi-bin/view/TWiki/EmptyPlugin. To copy the text, go to the page and:
   • click Edit
   • select all in the Edit box & copy
   • Cancel the edit
   • paste & save as a text file or new topic on your site
2. Customize the template for your Plugin; you'll probably want to post a working version on your local TWiki site.
3. Save your topic as a text file, for use in packaging and publishing your Plugin.

OUTLINE: Doc Topic Contents
Check EmptyPlugin on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:

Syntax Rules: explanation coming up

YourPlugin Settings: Description and settings for your custom Plugin %VARIABLES%, and those required by TWiki.

Plugins Preferences work exactly like TWikiPreferences and WebPreferences: six (6) spaces and then:

• • Set EXAMPLE = got it!

How-to Instructions: Step-by-step set-up guide, user help, whatever it takes to install and run, goes here.

Test Example: Include an example of the Plugin in action: if it works, the installation was a success!

Plugin Info: Version, credits, history, requirements - entered in a form, displayed as a table. Both are automatically generated when you create or edit a page in the TWiki:Plugins web.

Package a Plugin for Distribution

A minimum Plugin release consists of a Perl module with a WikiName that ends in Plugin, ex: YourPlugin.pm, and a documentation page with the same name(YourPlugin.txt).

1. Distribute your Plugin files in a directory structure that mirrors TWiki. If your Plugin uses additional files, include them ALL:
   • lib/TWiki/Plugins/YourPlugin.pm
   • data/TWiki/YourPlugin.txt
   • pub/TWiki/YourPlugin/uparrow.gif [a required graphic]
2. Create a zip archive with the Plugin name (YourPlugin.zip) and add the entire directory structure from Step 1. Your archive should look like this:
   • lib/TWiki/Plugins/YourPlugin.pm
   • data/TWiki/YourPlugin.txt
   • pub/TWiki/YourPlugin/uparrow.gif

Publish a Plugin for General Use

You can release your tested, packaged Plugin to the TWiki community through the TWiki:Plugins web, where all Plugins submitted to TWiki.org are available for download and further development discussion. Publish your Plugin in three steps:

1. Post the Plugin documentation topic in the TWiki:Plugins web:
   • create a new topic using the Plugin name, ex: YourPlugin.txt;
   • paste in the topic text from How to Create the Plugin Documentation Topic and Save.
2. Attach the distribution zip file to the topic, ex: YourPlugin.zip.
3. Link from the doc page to a new, blank page named after the Plugin, and ending in Dev, ex: YourPluginDev. This is the discussion page for future development. (User support for Plugins is handled in TWiki:Support.)

-- MikeMannix - 26 Aug 2001

-- PeterThoeny - 17 Feb 2001

Plugins under the hood

• All plugin modules that exist in the lib/TWiki/Plugins directory are activated automatically unless disabled by the DISABLEDPLUGINS preferences variable in TWikiPreferences. You can optionally list the installed plugins in the INSTALLEDPLUGINS preferences variable. This is useful to define the sequence of plugin execution, or to specify other webs then the TWiki web for the plugin topics. Settings in TWikiPreferences:
  • Set INSTALLEDPLUGINS = DefaultPlugin, ...
  • Set DISABLEDPLUGINS = EmptyPlugin, ...

• The %ACTIVATEDPLUGINS% variable shows all currently activated plugins. This variable is shown in TWikiPreferences for debug reasons.

• Search order for plugin topics: Full web.topicname name is used if specified in INSTALLEDPLUGINS, then the TWiki web is searched, then the current web.

• Plugin specific settings are done in individual plugin topics. Two settings are standard for each plugin:
  • One line description, used to form the bullets describing the plugins in the TextFormattingRules topic:
    • Set SHORTDESCRIPTION = Blah blah.
  • Debug plugin, output can be seen in data/debug.txt: (Se to 0 or 1)
    • Set DEBUG = 0
  • The settings can be retrieved as preferences variables like %<pluginname>_<var>%, i.e. %DEFAULTPLUGIN_SHORTDESCRIPTION% shows the description of the DefaultPlugin.

• The %PLUGINDESCRIPTIONS% variable shows a bullet list with descriptions of all currently activated plugins. This variable is based on %<plugin>_SHORTDESCRIPTION% preferences variables of individual topics and is shown in TextFormattingRules.

-- PeterThoeny - 14 Jul 2001

TWikiPreferences has the list of installed plugins and activated plugins.

TWiki Plugins

How to Create a Plugin

How to Create a Plugin

How to Install a Plugin

How to Install a Plugin

Plugins allow you to extend the syntax or functionality of TWiki. ...

How to Create a Plugin

under construction... ( check back at http://TWiki.org/cgi-bin/view/TWiki/TWikiPlugins )

How to Install a Plugin

under construction... ( check back at http://TWiki.org/cgi-bin/view/TWiki/TWikiPlugins )

-- PeterThoeny - 17 Feb 2001