<div>
<ul>
<li><a href="#TWiki Plugins"> TWiki Plugins</a><ul>
- <li><a href="#About Plugins"> About Plugins</a></li>
- <li><a href="#Installing Plugins"> Installing Plugins</a></li>
- <li><a href="#Pre-Installed Plugins"> Pre-Installed Plugins</a></li>
- <li><a href="#Managing Installed Plugins"> Managing Installed Plugins</a><ul>
- <li><a href="#Set Preferences for Individual P"> Set Preferences for Individual Plugins</a></li>
- <li><a href="#List Active Plugins Automaticall"> List Active Plugins Automatically </a></li>
+ <li><a href="#Overview"> Overview</a></li>
+ <li><a href="#Preinstalled Plugins"> Preinstalled Plugins</a></li>
+ <li><a href="#Installing Plugins"> Installing Plugins</a><ul>
+ <li><a href="#On-Site Pretesting"> On-Site Pretesting</a></li>
+ <li><a href="#Checking that Plugins are Workin"> Checking that Plugins are Working on a Live Server</a></li>
+ <li><a href="#A Note on Plugin Performance"> A Note on Plugin Performance</a></li>
</ul>
</li>
- <li><a href="#Creating New Plugins"> Creating New Plugins</a><ul>
+ <li><a href="#Managing Plugins"> Managing Plugins</a><ul>
+ <li><a href="#Setting Preferences"> Setting Preferences</a></li>
+ <li><a href="#Listing Active Plugins"> Listing Active Plugins</a></li>
+ </ul>
+ </li>
+ <li><a href="#The TWiki Plugin API"> The TWiki Plugin API</a><ul>
+ <li><a href="#Available Core Functions"> Available Core Functions</a></li>
+ <li><a href="#Predefined Hooks"> Predefined Hooks</a></li>
+ <li><a href="#Hints on Writing Fast Plugins"> Hints on Writing Fast Plugins</a></li>
+ <li><a href="#Plugin Version Detection"> Plugin Version Detection</a></li>
+ </ul>
+ </li>
+ <li><a href="#Creating Plugins"> Creating Plugins</a><ul>
+ <li><a href="#The _DefaultPlugin Alternative"> The DefaultPlugin Alternative</a></li>
<li><a href="#Anatomy of a Plugin"> Anatomy of a Plugin</a></li>
- <li><a href="#TWiki Plugin API"> TWiki Plugin API</a></li>
- <li><a href="#Customize the _DefaultPlugin"> Customize the DefaultPlugin</a></li>
- <li><a href="#Create a Plugin Module in Perl"> Create a Plugin Module in Perl</a></li>
- <li><a href="#Create a Plugin Documentation To"> Create a Plugin Documentation Topic</a></li>
- <li><a href="#Package a Plugin for Distributio"> Package a Plugin for Distribution</a></li>
- <li><a href="#Publish a Plugin for General Use"> Publish a Plugin for General Use</a></li>
+ <li><a href="#Creating the Perl Module"> Creating the Perl Module </a></li>
+ <li><a href="#Writing the Documentation Topic"> Writing the Documentation Topic</a></li>
+ <li><a href="#Packaging for Distribution"> Packaging for Distribution</a></li>
+ <li><a href="#Publishing for Public Use"> Publishing for Public Use</a></li>
+ </ul>
+ </li>
+ <li><a href="#Recommended Storage of Plugin Da"> Recommended Storage of Plugin Data</a><ul>
+ <li><a href="#Where to store Plugin Internal D"> Where to store Plugin Internal Data</a></li>
+ <li><a href="#Where to Store Data for Topics u"> Where to Store Data for Topics using the Plugin</a></li>
</ul>
</li>
</ul>
</ul>
</div>
-## <a name="TWiki Plugins"></a> TWiki Plugins
+# <a name="TWiki Plugins"></a> TWiki Plugins
-### <a name="About Plugins"></a> About Plugins
+_Plug-in enhanced feature add-ons, with a Plugin API for developers_
-TWikiPlugins allow you to add new features to TWiki without changing the core program. Using a plug-in approach means that you can:
+## <a name="Overview"></a> Overview
-- add virtually unlimited features while keeping the main TWiki program compact and efficient;
+You can add Plugins to extend TWiki's functionality, without altering the core program code. A plug-in approach lets you:
+
+- add virtually unlimited features while keeping the main TWiki code 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.
-Everything to do with TWiki Plugins - including demos, new releases, downloads, and discussion - is available at TWiki.org, in the ** [TWiki.org Plugins web](http://twiki.org/cgi-bin/view/Plugins)**.
+Everything to do with TWiki Plugins - demos, new releases, downloads, development, general discussion - is available at TWiki.org, in the ** TWiki:Plugins ** web.
+
+## <a name="Preinstalled Plugins"></a> Preinstalled Plugins
+
+TWiki comes with a set of Plugins as part of the standard installation.
+
+- [[DefaultPlugin]]: Optionally handles some legacy variables from older versions of TWiki. You can control this option from [[TWikiPreferences]]. (Perl programmers can also [[add rules|Main/WebHome#DefaultPluginAlt]] 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.
+- [[InterwikiPlugin]]: 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.
+- [[EditTablePlugin]]: %EDITTABLEPLUGIN\_SHORTDESCRIPTION%
+- [[RenderListPlugin]]: %RENDERLISTPLUGIN\_SHORTDESCRIPTION%
+- [[SlideShowPlugin]]: %SLIDESHOWPLUGIN\_SHORTDESCRIPTION%
+- [[SmiliesPlugin]]: %SMILIESPLUGIN\_SHORTDESCRIPTION%
+- [[SpreadSheetPlugin]]: %SPREADSHEETPLUGIN\_SHORTDESCRIPTION%
+- [[TablePlugin]]: %TABLEPLUGIN\_SHORTDESCRIPTION%
<a name="InstallPlugin"></a>
-### <a name="Installing Plugins"></a> Installing Plugins
+## <a name="Installing Plugins"></a> Installing Plugins
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.
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!
-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: <code>**SomePlugin**</code>) 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.
- **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 <code>**Dev**</code> (ex: <code>**SomePluginDev**</code>).
+- **Dev page:** Post feature requests, bug reports and general dev comments; topic title ends in `Dev` (`SomePluginDev`).
- **User support:** Post installation, how to use type questions (and answers, if you have them) in the TWiki:Support web.
-### <a name="Pre-Installed Plugins"></a> Pre-Installed Plugins
+<a name="PreTesting"></a>
+
+### <a name="On-Site Pretesting"></a> 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|Main/WebHome#Customize_the_DefaultPlugin]] for simple custom processing.)
+- **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, and adjust the paths in the new `lib/TWiki.cfg`. The following directories are shared: `twiki/data`, `twiki/templates` and `twiki/pub`.
+ - **Test** Plugins and other new features in the Test installation until you're satisfied.
+ - %X% 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.
-- **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 being tested in the `DISABLEDPLUGINS` variable in [[TWikiPreferences]]. Redefine the `DISABLEDPLUGINS` variable in the `Sandbox` 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: <code>**TWiki:Plugins**</code> expands to TWiki:Plugins - on TWiki.org. You can add your own shortcuts and URLs to the existing directory of Wiki-related sites.
+### <a name="Checking that Plugins are Workin"></a> Checking that Plugins are Working on a Live Server
-### <a name="Managing Installed Plugins"></a> Managing Installed Plugins
+[[InstalledPlugins]] shows which Plugins are: 1) installed, 2) loading properly and 3) what TWiki:Codev.PluginHandlers they invoke. Any failures are shown in the Errors section.
-Ideally, after you've [[installed a Plugin|Main/WebHome#InstallPlugin]], 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.
+### <a name="A Note on Plugin Performance"></a> A Note on Plugin Performance
-#### <a name="Set Preferences for Individual P"></a> Set Preferences for Individual Plugins
+The performance of the system depends on the number of Plugins installed and on the Plugin implementation. Some Plugins impose no measurable performance decrease, some do. For example, `outsidePREHandler` is an expensive callback function, or a Plugin might use many Perl libraries that need to be initialized with each page view (unless you run mod\_perl). It is recommended to measure the performance with and without a new Plugin. Example for Unix:%BR% `time wget -qO /dev/null http://www.dementia.org/twiki//view/TWiki/AbcPlugin`
-Installed Plugins can be **toggled on or off**, site-wide or by web, through [[TWikiPreferences]] and individual [[WebPreferences]]:
+In case you need to install an "expensive" Plugin and you need its functionality only in one web you can place the Plugin topic into that web. TWiki will initialize the Plugin only if the Plugin topic is found (which won't be the case for other webs.)
-- All Plugin modules present in the <code>**lib/TWiki/Plugins**</code> directory are activated automatically unless disabled by the <code>**DISABLEDPLUGINS**</code> Preferences variable in TWikiPreferences. You can optionally list the installed Plugins in the <code>**INSTALLEDPLUGINS**</code> Preferences variable. This is useful to define the sequence of Plugin execution, or to specify other webs than the %WIKITOOLNAME% web for the Plugin topics. Settings in [[TWikiPreferences]] are:
- - <code>**Set INSTALLEDPLUGINS = DefaultPlugin, ...**</code>
- - <code>**Set DISABLEDPLUGINS = EmptyPlugin, ...**</code>
+## <a name="Managing Plugins"></a> Managing Plugins
-**Plugin execution order** in TWiki is determined by searching Plugin topics in a specific sequence: First, full <code>**web.topicname**</code> name, if specified in <code>**INSTALLEDPLUGINS**</code>; next, the TWiki web is searched; and finally, the current web.
+When you finish [[installing a Plugin|Main/WebHome#InstallPlugin]], 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.
+
+### <a name="Setting Preferences"></a> Setting Preferences
+
+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 %WIKITOOLNAME% 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:
- - <code>**Set SHORTDESCRIPTION = Blah blah woof woof.**</code>
-2. Debug Plugin, output can be seen in <code>**data/debug.txt**</code>. Set to 0=off or 1=on:
- - <code>**Set DEBUG = 0**</code>
+ - `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 <code>**%<pluginname>\_<var>%**</code>, ex: <code>**%DEFAULTPLUGIN\_SHORTDESCRIPTION%**</code> shows the description of the DefaultPlugin.
+- The settings can be retrieved as Preferences variables like `%<pluginname>_<var>%`, ex: `%DEFAULTPLUGIN_SHORTDESCRIPTION%` shows the description of the DefaultPlugin.
-#### <a name="List Active Plugins Automaticall"></a> List Active Plugins Automatically
+### <a name="Listing Active Plugins"></a> Listing Active Plugins
Plugin status variables let you list all active Plugins wherever needed. There are two list formats:
-- The <code>**%ACTIVATEDPLUGINS%**</code> variable lists activated Plugins by name. (This variable is displayed in [[TWikiPreferences]] for debugging use.)
-- The <code>**%PLUGINDESCRIPTIONS%**</code> variable displays a bullet list with a one-line description of each active Plugins. This variable is based on the <code>**%<plugin>\_SHORTDESCRIPTION%**</code> 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]].
-> <span><font> **DEMO: Active Plugin Variables** </font></span>
+> **DEMO: Automatically List Active Plugins Using Variables**
>
-> <code>**%ACTIVATEDPLUGINS%**</code><br /> On this TWiki site, the active Plugins are: [[SpreadSheetPlugin]], [[CommentPlugin]], [[EditTablePlugin]], [[InterwikiPlugin]], [[PreferencesPlugin]], [[SlideShowPlugin]], [[SmiliesPlugin]], [[TablePlugin]], [[TwistyPlugin]].
+> Using `%ACTIVATEDPLUGINS%`:<br /> On this TWiki site, the active Plugins are: [[SpreadSheetPlugin]], [[CommentPlugin]], [[EditTablePlugin]], [[InterwikiPlugin]], [[PreferencesPlugin]], [[SlideShowPlugin]], [[SmiliesPlugin]], [[TablePlugin]], [[TwistyPlugin]].
>
-> <code>**%PLUGINDESCRIPTIONS%**</code><br /> You can use any of these active TWiki Plugins:
+> Using <code>%PLUGINDESCRIPTIONS%</code>:<br /> You can use any of these active TWiki Plugins:
>
> - [[SpreadSheetPlugin]] <span>(any TWiki, 10197)</span>:
> - [[CommentPlugin]] <span>(Dakar, 11359)</span>: Allows users to quickly post comments to a page without an edit/preview/save cycle
> - [[TablePlugin]] <span>(1.020, 12339)</span>:
> - [[TwistyPlugin]] <span>(1.2.0, $Rev: 12154$)</span>:
-**TIP! To test new Plugins** on your installation before making them public, you may want to use one of these two approaches:
+<a name="PluginAPI"></a>
-- **Method 1:** Create a Production and a Test installation of TWiki. The <code>**twiki/data**</code>, <code>**twiki/templates**</code> and <code>**twiki/pub**</code> directories are shared, and the <code>**twiki/bin**</code> and <code>**twiki/lib**</code> 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.
+## <a name="The TWiki Plugin API"></a> The TWiki Plugin API
-- **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.
+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.
-<a name="CreatePlugins"></a>
+### <a name="Available Core Functions"></a> Available Core Functions
-### <a name="Creating New Plugins"></a> Creating New Plugins
+The [[TWikiFuncModule]] (`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|Main/WebHome#PluginAPI]] Plugins by providing a programming interface for TWiki.
+%X% 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.
-#### <a name="Anatomy of a Plugin"></a> Anatomy of a Plugin
+### <a name="Predefined Hooks"></a> Predefined Hooks
-A basic TWiki Plugin consists of two elements:
+In addition to TWiki core functions, Plugins can use **predefined hooks**, or **call backs**, listed in the `lib/TWiki/Plugins/EmptyPlugin.pm` module.
-- a Perl module, ex: <code>**YourPlugin.pm**</code>
-- a documentation topic, ex: <code>**YourPlugin.txt**</code>
+- All but the initPlugin are disabled. To enable a call back, remove `DISABLE_` from the function name.
+- For best performance, enable only the functions you really need. NOTE: `outsidePREHandler` and `insidePREHandler` are particularly expensive.
-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.
+Most Plugins use either the `commonTagsHandler` or `startRenderingHandler` for rendering tasks:
-The Plugin API handles the details of connecting your Perl module with main TWiki code. When you're familiar with the [[Plugin API|Main/WebHome#PluginAPI]], you're ready to develop Plugins.
+- `commonTagsHandler:` Use it to expand `%XYZPLUGIN%` and `%XYZPLUGIN{...}%` variables
+- `startRenderingHandler:` Use it for your own rendering rules or to overload TWiki's internal rendering like `[[links]]`
-<a name="PluginAPI"></a>
+TWiki:Codev/StepByStepRenderingOrder helps you decide which rendering handler to use.
-#### <a name="TWiki Plugin API"></a> TWiki Plugin API
+### <a name="Hints on Writing Fast Plugins"></a> Hints on Writing Fast Plugins
-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.
+- Delay the Plugin initialization to the actual function which is handling the tag. This way all the expensive initialization is done only when needed.
+- For example, use an `eval` block like:%BR% `eval { require IPC::Run }` %BR% `return "<font color=\"red\">SamplePlugin: Can't load required modules ($@)</font>" if $@;`
+- You could return errors as strings to show what happened
+- You can use a flag to avoid running the initialization twice
-The <code>**lib/TWiki/Func.pm**</code> implements ALL official Plugin functions. Plugins should ONLY use functions published in this module.
+### <a name="Plugin Version Detection"></a> Plugin Version Detection
-<span><font>**DevALERT:**</font></span> If you use functions not in <code>**Func.pm**</code>, you run the risk of creating security holes. Also, your Plugin will likely break and require updating when you upgrade to a new version of TWiki.
+To eliminate the incompatibility problems bound to arise from active open Plugin development, a Plugin versioning system and an API `GetVersion` detection routine are provided for automatic compatibility checking.
-In addition to TWiki core functions, Plugins can use **predefined hooks**, or **call backs**, listed in the <code>**lib/TWiki/Plugins/EmptyPlugin.pm**</code> module.
+- All modules require a `$VERSION='0.000'` variable, beginning at `1.000`.
-- All but the initPlugin are disabled. To enable a call back, remove <code>**DISABLE\_**</code> from the function name.
+- 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).
-- For improve performance, enable only the functions you really need. NOTE: <code>**outsidePREHandler**</code> and <code>**insidePREHandler**</code> are particularly expensive.
+- `$VERSION='1.000'` is the current setting in `TWiki::Plugins.pm` and in the preinstalled system Plugins ([[DefaultPlugin]], [[EmptyPlugin]], [[InterwikiPlugin]]).
-#### <a name="Customize the _DefaultPlugin"></a> Customize the DefaultPlugin
+<a name="CreatePlugins"></a>
-- **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.
+## <a name="Creating Plugins"></a> Creating Plugins
-#### <a name="Create a Plugin Module in Perl"></a> Create a Plugin Module in Perl
+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|Main/WebHome#PluginAPI]] Plugins by providing a programming interface for TWiki.
+
+<a name="DefaultPluginAlt"></a>
+
+### <a name="The _DefaultPlugin Alternative"></a> The DefaultPlugin Alternative
+
+- **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 name="Anatomy of a Plugin"></a> Anatomy of a Plugin
+
+A basic TWiki Plugin consists of two elements:
+
+- a Perl module, ex: `MyFirstPlugin.pm`
+- a documentation topic, ex: `MyFirstPlugin.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. 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.
+
+The Plugin API handles the details of connecting your Perl module with main TWiki code. When you're familiar with the [[Plugin API|Main/WebHome#PluginAPI]], you're ready to develop Plugins.
-Copy file ([`EmptyPlugin.pm`](http://twiki.org/lib/TWiki/Plugins/EmptyPlugin.pm) to <code>**<name>Plugin.pm**</code> <code>**EmptyPlugin.pm**</code> contains no executable code, so it does nothing, but it's ready to be used. Customize it. Refer to the [[Plugin API|Main/WebHome#PluginAPI]] specs for more information.
+### <a name="Creating the Perl Module"></a> Creating the Perl Module
+
+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|Main/WebHome#PluginAPI]] 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();
<a name="CreatePluginTopic"></a>
-#### <a name="Create a Plugin Documentation To"></a> Create a Plugin Documentation Topic
+### <a name="Writing the Documentation Topic"></a> Writing the 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|Main/WebHome#CreatePluginPackage]].) 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
+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
- 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|Main/WebHome#CreatePluginPackage]] and [[publishing|Main/WebHome#PublishPlugin]] your Plugin.
-
-> <span><font>**OUTLINE:** Doc Topic Contents </font></span>
+ - 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
+2. **Customize** your Plugin topic.
+ - In case you plan to publish your Plugin at TWiki.org, use Interwiki names for author names, like TWiki:Main/admin.
+3. **Save** your topic, for use in [[packaging|Main/WebHome#CreatePluginPackage]] and [[publishing|Main/WebHome#PublishPlugin]] your Plugin.
+
+> **OUTLINE: Doc Topic Contents**
>
> <br />
>
-> Check
->
-> [EmptyPlugin](http://TWiki.org/cgi-bin/view/TWiki/EmptyPlugin)
+> Check the Plugins web on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:
>
-> on TWiki.org for the latest Plugin doc topic template. Here's a quick overview of what's covered:
+> **Syntax Rules:** <_Describe any special text formatting that will be rendered._>"
>
-> **Syntax Rules:** **_explanation coming up_**
+> **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!_>"
>
-> **YourPlugin Settings:** Description and settings for your custom Plugin %VARIABLES%, and those required by TWiki.
+> **Plugin 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:
+> - **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_>**
>
-> - - Set EXAMPLE = got it!
+> **Plugin Installation 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!
->
-> **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._>"
<a name="CreatePluginPackage"></a>
-#### <a name="Package a Plugin for Distributio"></a> Package a Plugin for Distribution
+### <a name="Packaging for Distribution"></a> Packaging for Distribution
-A minimum Plugin release consists of a Perl module with a [[WikiName]] that ends in <code>**Plugin**</code>, ex: <code>**YourPlugin.pm**</code>, and a documentation page with the same name(<code>**YourPlugin.txt**</code>).
+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:
- - <code>**lib/TWiki/Plugins/YourPlugin.pm**</code>
- - <code>**data/TWiki/YourPlugin.txt**</code>
- - <code>**pub/TWiki/YourPlugin/uparrow.gif**</code> [a required graphic]
-2. Create a zip archive with the Plugin name (<code>**YourPlugin.zip**</code>) and add the entire directory structure from Step 1. Your archive should look like this:
- - <code>**lib/TWiki/Plugins/YourPlugin.pm**</code>
- - <code>**data/TWiki/YourPlugin.txt**</code>
- - <code>**pub/TWiki/YourPlugin/uparrow.gif**</code>
+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`
<a name="PublishPlugin"></a>
-#### <a name="Publish a Plugin for General Use"></a> 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: <code>**YourPlugin.txt**</code>;
- - paste in the topic text from [[How to Create the Plugin Documentation Topic|Main/WebHome#CreatePluginTopic]] and Save.
-2. **Attach** the distribution zip file to the topic, ex: <code>**YourPlugin.zip**</code>.
-3. **Link** from the doc page to a new, blank page named after the Plugin, and ending in <code>**Dev**</code>, ex: <code>**YourPluginDev**</code>. This is the discussion page for future development. (User support for Plugins is handled in TWiki:Support.)
-
--- [[MikeMannix]] - 26 Aug 2001
+### <a name="Publishing for Public Use"></a> Publishing for Public Use
+
+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/PluginPackage. Publish your Plugin in these steps:
+
+1. **Post** the Plugin documentation topic in the TWiki:Plugins/PluginPackage:
+ - enter the Plugin name in the "How to Create a Plugin" section, for example `MyFirstPlugin`
+ - paste in the topic text from [[Creating Plugin Documentation|Main/WebHome#CreatePluginTopic]] and save
+2. **Attach** the distribution zip file to the topic, ex: `MyFirstPlugin.zip`
+3. **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.)
+4. **Put** the Plugin into the CVS repository, see TWiki:Plugins/ReadmeFirst (optional)
+
+Thank you very much for sharing your Plugin with the TWiki community :-)
+
+<a name="RecommendedStorageOfPluginData"></a>
+
+## <a name="Recommended Storage of Plugin Da"></a> Recommended Storage of Plugin Data
+
+Plugins sometimes need to store data. This can be Plugin internal data like cache data, or generated data for the browser like images. The following is a recommendation where to store the data.
+
+### <a name="Where to store Plugin Internal D"></a> Where to store Plugin Internal Data
+
+In case the Plugin generates data just for internal use, or data which is not specific to a topic, store it in the Plugin's attachment directory.
+
+- The Plugin's attachment directory is `pubdir/Installweb/FooBarPlugin`
+ - `Installweb` refers to the name of the web where the Plugin is installed
+- The Plugin's attachment URL is `%PUBURL%/Installweb/FooBarPlugin`
+- The filename should start with an underscore, followed by an identifier, e.g. `_any_name.ext`
+ - The leading underscore avoids a nameclash with files attached to the Plugin topic
+ - Use only alphanumeric characters, underscores and periods to avoid platform dependency issues and URL issues
+ - Do not use subdirectories (rename and delete would fail)
+- Use Plugin API functions documented in [[TWikiFuncModule]] to ensure portability:
+ - Use `getPubDir()` to get the attachment root directory
+ - Use `getUrlHost()` and `getPubUrlPath()` to build the URL in case you create content for the browser
+ - Use `$installWeb` to get the name of the web where the Plugin is installed
+ - Create the web directory and topic attachment directory if needed
+- Hint: Package the Plugin at least with one file attachment. This ensures that the attachment directory already exists
+
+### <a name="Where to Store Data for Topics u"></a> Where to Store Data for Topics using the Plugin
+
+In case the Plugin generates data which is specific to a topic, store it in the topic's attachment directory.
+
+- The topic's attachment directory is `pubdir/Webname/TopicName`
+- The topic's attachment URL is `%PUBURL%/Webname/TopicName`
+- The filename should start with an underscore, followed by the Plugin name, an underscore and an identifier, e.g. `_FooBarPlugin_any_name.ext`
+ - The leading underscore avoids a nameclash with files attached to the same topic
+ - Use only alphanumeric characters, underscores and periods to avoid platform dependency issues and URL issues
+ - Do not use subdirectories (rename and delete would fail)
+- Use Plugin API functions documented in [[TWikiFuncModule]] to ensure portability:
+ - Use `getPubDir()` to get the attachment root directory
+ - Use `getUrlHost()` and `getPubUrlPath()` to build the URL in case you create content for the browser
+
+Example code to build the file name:
+
+ sub _make_filename
+ {
+ my ( $web, $topic, $name ) = @_;
+
+ # Create web directory "pub/$web" if needed
+ my $dir = TWiki::Func::getPubDir() . "/$web";
+ unless( -e "$dir" ) {
+ umask( 002 );
+ mkdir( $dir, 0775 );
+ }
+ # Create topic directory "pub/$web/$topic" if needed
+ $dir .= "/$topic";
+ unless( -e "$dir" ) {
+ umask( 002 );
+ mkdir( $dir, 0775 );
+ }
+ return "$dir/_FooBarPlugin_$name";
+ }
+
+-- TWiki:Main/PeterThoeny - 18 May 2004 %BR% -- TWiki:Main/AndreaSterbini - 29 May 2001 %BR% -- TWiki:Main/MikeMannix - 03 Dec 2001
git://git.openafs.org / openafs-wiki.git / blobdiff