X-Git-Url: https://sipb.mit.edu/gitweb.cgi/ikiwiki.git/blobdiff_plain/a0d372751a79bf426ddcde89ada051bf748d8603..253c4a9acc4c1cde24a6c63aab88447dbc293756:/doc/plugins/write.mdwn diff --git a/doc/plugins/write.mdwn b/doc/plugins/write.mdwn index 0f2c26344..969862842 100644 --- a/doc/plugins/write.mdwn +++ b/doc/plugins/write.mdwn @@ -17,39 +17,93 @@ being edited. ## Registering plugins -Plugins should, when imported, call IkiWiki::register_plugin to hook into -ikiwiki. The function takes four parameters: - -1. A method type. Use "preprocess" to register a [[PreProcessorDirective]] -2. A command name. This is the bit that will appear inside brackets in a - page. -3. A reference to a subroutine that is run when the plugin is used. +Plugins should, when imported, call IkiWiki::hook to hook into ikiwiki's +processing. The function uses named parameters, and use varies depending on +the type of plugin being registered. Note that a plugin can call the +function more than once to register multiple hooks. All calls to +IkiWiki::hook should be passed a "type" parameter, which gives the type of +hook, a "id" paramter, which should be a unique string for this plugin, and +a "call" parameter, which is a reference to a function to call for the +hook. ## Writing a [[PreProcessorDirective]] -For preprocessor directives, the subroutine is passed named parameters. A +This is probably the most common use of a plugin. + + IkiWiki::hook(type => "preprocess", id => "foo", call => \&preprocess); + +Replace "foo" with the command name that will be used inside brackers for +the preprocessor directive. + +Each time the directive is processed, the referenced function (`preprocess` in the example above) is called, and is passed named parameters. A "page" parameter gives the name of the page that embedded the preprocessor directive. All parameters included in the directive are included -as named parameters as well. Whatever the subroutine returns goes onto the +as named parameters as well. Whatever the function returns goes onto the page in place of the directive. -## Error handing in plugins +### Error handing While a plugin can call ikiwiki's error routine for a fatal error, for errors that aren't intended to halt the entire wiki build, including bad parameters passed to a [[PreProcessorDirective]], etc, it's better to just return the error message as the output of the plugin. -## Html issues +### Html issues Note that if [[HTMLSanitization]] is enabled, html in [[PreProcessorDirective]] output is sanitised, which may limit what your plugin can do. Also, the rest of the page content is not in html format at preprocessor time. Text output by a preprocessor directive will be passed through markdown along with the rest of the page. +## Other types of hooks + +Beyond PreProcessorDirectives, Other types of hooks that can be used by +plugins include: + +### checkconfig + + IkiWiki::hook(type => "checkconfig", id => "foo", call => \&checkconfig); + +This is useful if the plugin needs to check for, or modify ikiwiki's +configuration. It's called early in the ikiwiki startup process. The +function is passed no values. It's ok for the function to call +IkiWiki::error if something isn't configured right. + +### filter + + IkiWiki::hook(type => "filter", id => "foo", call => \&filter); + +Runs on the raw source of a page, before anything else touches it, and can +make arbitrary changes. The function is passed named parameters `page` and +`content` should return the filtered content. + +### delete + + IkiWiki::hook(type => "delete", id => "foo", call => \&dele); + +Each time a page or pages is removed from the wiki, the referenced function +is called, and passed the names of the source files that were removed. + +### render + + IkiWiki::hook(type => "render", id => "foo", call => \&render); + +Each time ikiwiki renders a change or addition (but not deletion) of a page +to the wiki, the referenced function is called, and passed the name of the +source file that was rendered. + +### cgi + + IkiWiki::hook(type => "cgi", id => "foo", call => \&cgi); + +Use this to hook into ikiwiki's cgi script. Each registered cgi hook is +called in turn, and passed a CGI object. The hook should examine the +parameters, and if it will handle this CGI request, output a page and +terminate the program. + ## Wiki configuration -A plugin can access the wiki's configuration via the `%IkiWiki::config` hash. -The best way to understand the contents of the hash is to look at +A plugin can access the wiki's configuration via the `%IkiWiki::config` +hash. The best way to understand the contents of the hash is to look at [[ikiwiki.setup]], which sets the hash content to configure the wiki. ## Wiki data @@ -58,9 +112,9 @@ If your plugin needs to access data about other pages in the wiki. It can use the following hashes, using a page name as the key: * `%IkiWiki::links` lists the names of each page - that is linked to from that page in an array reference. + that a page links to, in an array reference. * `%IkiWiki::pagemtime` contains the last modification time of each page -* `%IkiWiki::pagectime` contains the creation time of each page` +* `%IkiWiki::pagectime` contains the creation time of each page * `%IkiWiki::renderedfiles` contains the name of the file rendered by a page * `%IkiWiki::pagesources` contains the name of the source file for a page. @@ -71,3 +125,27 @@ use the following hashes, using a page name as the key: Many plugins will need to add dependencies to this hash; the best way to do it is by using the IkiWiki::add_depends function, which takes as its parameters the page name and a [[GlobList]] of dependencies to add. + +## Page templates + +Plugins are mostly limited to changing the content of pages, to change the +look and feel of the wiki it's generally better to use a stylesheet and +[[templates]]. However, there are some hooks in the templates that plugins +can use to add stuff to the wiki's UI: + +### Adding content to the page header + +Html that is added to $IkiWiki::config{headercontent} will show up in the +header of the page. One good thing to put here is a search form. + +## RCS plugins + +ikiwiki's support for revision control systems also uses pluggable perl +modules. These are in the `IkiWiki::RCS` namespace, for example +`IkiWiki::RCS::svn`. + +Each RCS plugin must support all the IkiWiki::rcs\_* functions. +See IkiWiki::RCS::Stub for the full list of functions. It's ok if +rcs\_getctime does nothing except for throwing an error. + +See [[about_RCS_backends]] for some more info.