-lkiwiki's plugin interface allows all kinds of useful [[plugins]] to be
+Ikiwiki's plugin interface allows all kinds of useful [[plugins]] to be
written to extend ikiwiki in many ways. Despite the length of this page,
it's not really hard. This page is a complete reference to everything a
plugin might want to do. There is also a quick [[tutorial]].
### compiler
-As a compiler, ikiwiki starts by calling the `refresh` hook. Then it checks
-the wiki's source to find new or changed pages. The `needsbuild` hook is
-then called to allow manipulation of the list of pages that need to be
-built.
-
-Now that it knows what pages it needs to build, ikiwiki runs two
-compile passes. First, it runs `scan` hooks, which collect metadata about
-the pages. Then it runs a page rendering pipeline, by calling in turn these
-hooks: `filter`, `preprocess`, `linkify`, `htmlize`, `indexhtml`,
-`pagetemplate`, `sanitize`, `format`.
-
-After all necessary pages are built, it calls the `change` hook. Finally,
-if a page is was deleted, the `delete` hook is called, and the files that
-page had previously produced are removed.
+As a compiler, ikiwiki starts by calling the
+[[`refresh`|plugins/write#refresh]] hook. Then it checks the wiki's source to
+find new or changed pages. The [[`needsbuild`|plugins/write#needsbuild]] hook
+is then called to allow manipulation of the list of pages that need to be
+built.
+
+Now that it knows what pages it needs to build, ikiwiki runs two compile
+passes. First, it runs [[`scan`|plugins/write#scan]] hooks, which collect
+metadata about the pages. Then it runs a page rendering pipeline, by calling
+in turn these hooks: [[`filter`|plugins/write#filter]],
+[[`preprocess`|plugins/write#preprocess]],
+[[`linkify`|plugins/write#linkify]], [[`htmlize`|plugins/write#htmlize]],
+[[`indexhtml`|plugins/write#indexhtml]],
+[[`pagetemplate`|plugins/write#pagetemplate]],
+[[`sanitize`|plugins/write#sanitize]], [[`format`|plugins/write#format]].
+
+After all necessary pages are built, it calls the
+[[`changes`|plugins/write#changes]] hook. Finally, if a page was deleted, the
+[[`delete`|plugins/write#delete]] hook is called, and the files that page had
+previously produced are removed.
### cgi
Alice browses to a page and clicks Edit.
-* Ikiwiki is run as a cgi. It assigns Alice a session cookie, and,
- by calling the `auth` hooks, sees that she is not yet logged in.
-* The `sessioncgi` hooks are then called, and one of them,
- from the [[editpage]] plugin, notices that the cgi has been told "do=edit".
-* The [[editpage]] plugin calls the `canedit` hook to check if this
- page edit is allowed. The [[signinedit]] plugin has a hook that says not:
- Alice is not signed in.
-* The [[signinedit]] plugin then launches the signin process. A signin
- page is built by calling the `formbuilder_setup` hook.
+* Ikiwiki is run as a cgi. It assigns Alice a session cookie, and, by calling
+ the [[`auth`|plugins/write#auth]] hooks, sees that she is not yet logged in.
+* The [[`sessioncgi`|plugins/write#sessioncgi]] hooks are then called, and one
+ of them, from the [[editpage]] plugin, notices that the cgi has been told
+ "do=edit".
+* The [[editpage]] plugin calls the [[`canedit`|plugins/write#canedit]] hook
+ to check if this page edit is allowed. The [[signinedit]] plugin has a hook
+ that says not: Alice is not signed in.
+* The [[signinedit]] plugin then launches the signin process. A signin page is
+ built by calling the [[`formbuilder_setup`|plugins/write#formbuilder]]
+ hook.
Alice signs in with her openid.
-* The [[openid]] plugin's `formbuilder` hook sees that an openid was
- entered in the signin form, and redirects to Alice's openid provider.
-* Alice's openid provider calls back to ikiwiki. The [[openid]] plugin
- has an `auth` hook that finishes the openid signin process.
+* The [[openid]] plugin's [[`formbuilder`|plugins/write#formbuilder]] hook
+ sees that an openid was entered in the signin form, and redirects to Alice's
+ openid provider.
+* Alice's openid provider calls back to ikiwiki. The [[openid]] plugin has an
+ [[`auth`|plugins/write#auth]] hook that finishes the openid signin process.
* Signin complete, ikiwiki returns to what Alice was doing before; editing
a page.
-* Now all the `canedit` hooks are happy. The [[editpage]] plugin calls
- `formbuilder_setup` to display the page editing form.
+* Now all the [[`canedit`|plugins/write#canedit]] hooks are happy. The
+ [[editpage]] plugin calls
+ [[`formbuilder_setup`|plugins/write#formbuilder]] to display the page
+ editing form.
Alice saves her change to the page.
-* The [[editpage]] plugin's `formbuilder` hook sees that the Save button
- was pressed, and calls the `checkcontent` and `editcontent` hooks.
- Then it saves the page to disk, and branches into the compiler part
- of ikiwiki to refresh the wiki.
+* The [[editpage]] plugin's [[`formbuilder`|plugins/write#formbuilder]] hook
+ sees that the Save button was pressed, and calls the
+ [[`checkcontent`|plugins/write#checkcontent]] and
+ [[`editcontent`|plugins/write#editcontent]] hooks. Then it saves the page
+ to disk, and branches into the compiler part of ikiwiki to refresh the wiki.
## Types of plugins
The function is passed no values. It's ok for the function to call
`error()` if something isn't configured right.
-### refresh
+### <a name="refresh">refresh</a>
hook(type => "refresh", id => "foo", call => \&refresh);
It's useful for plugins that need to create or modify a source page. The
function is passed no values.
-### needsbuild
+### <a name="needsbuild">needsbuild</a>
hook(type => "needsbuild", id => "foo", call => \&needsbuild);
The second parameter passed to the function is a reference to an array of
files that have been deleted.
-### scan
+### <a name="scan">scan</a>
hook(type => "scan", id => "foo", call => \&scan);
The function is passed named parameters "page" and "content". Its return
value is ignored.
-### filter
+### <a name="filter">filter</a>
hook(type => "filter", id => "foo", call => \&filter);
can make arbitrary changes. The function is passed named parameters "page",
"destpage", and "content". It should return the filtered content.
-### preprocess
+### <a name="preprocess">preprocess</a>
Adding a preprocessor [[ikiwiki/directive]] is probably the most common use
of a plugin.
be linkified and passed through markdown (or whatever engine is used to
htmlize the page) along with the rest of the page.
-### linkify
+### <a name="linkify">linkify</a>
hook(type => "linkify", id => "foo", call => \&linkify);
for the links on the page and adds them to `%links` (typically by calling
`add_link`).
-### htmlize
+### <a name="htmlize">htmlize</a>
hook(type => "htmlize", id => "ext", call => \&htmlize);
If `hook` is passed an optional "longname" parameter, this value is used
when prompting a user to choose a page type on the edit page form.
-### indexhtml
+### <a name="indexhtml">indexhtml</a>
hook(type => "indexhtml", id => "foo", call => \&indexhtml);
The function is passed named parameters "page", "destpage", and "content".
Its return value is ignored.
-### pagetemplate
+### <a name="pagetemplate">pagetemplate</a>
hook(type => "pagetemplate", id => "foo", call => \&pagetemplate);
parameter, and can return a list of html fragments to add to the action
bar.
-### sanitize
+### <a name="sanitize">sanitize</a>
hook(type => "sanitize", id => "foo", call => \&sanitize);
The function is passed named parameters: "page", "destpage", and "content",
and should return the sanitized content.
-### format
+### <a name="format">format</a>
hook(type => "format", id => "foo", call => \&format);
The function is passed named parameters: "page" and "content", and
should return the formatted content.
-### delete
+### build_affected
+
+ hook(type => "build_affected", id => "foo", call => \&build_affected);
+
+This hook is called after the directly changed pages have been built,
+and can cause extra pages to be built. If links and backlinks were provided
+by a plugin, this would be where that plugin would rebuild pages whose
+backlinks have changed, for instance. The [[trail]] plugin uses this hook
+to rebuild pages whose next or previous page has changed.
+
+The function should currently ignore its parameters. It returns a list with
+an even number of items (a hash in list context), where the first item of
+each pair is a page name to be rebuilt (if it was not already rebuilt), and
+the second is a log message resembling
+`building plugins/write because the phase of the moon has changed`.
+
+### <a name="delete">delete</a>
hook(type => "delete", id => "foo", call => \&delete);
-Each time a page or pages is removed from the wiki, the referenced function
+After 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.
-### change
+### rendered
- hook(type => "change", id => "foo", call => \&render);
+ hook(type => "rendered", id => "foo", call => \&rendered);
-Each time ikiwiki renders a change or addition (but not deletion) to the
+After ikiwiki renders a change or addition (but not deletion) to the
wiki, the referenced function is called, and passed the names of the
source files that were rendered.
+(This hook used to be called "change", but that was not accurate.
+For now, plugins using the old hook name will still work.)
+
+### <a name="changes">changes</a>
+
+ hook(type => "changes", id => "foo", call => \&changes);
+
+After ikiwiki renders changes to the wiki, the referenced function is
+called, and passed the names of the source files that were added, modified,
+or deleted.
+
### cgi
hook(type => "cgi", id => "foo", call => \&cgi);
Note that cgi hooks are called as early as possible, before any ikiwiki
state is loaded, and with no session information.
-### auth
+### <a name="auth">auth</a>
hook(type => "auth", id => "foo", call => \&auth);
if the name is set to the name of a user who is not registered,
a basic registration of the user will be automatically performed.
-### sessioncgi
+### <a name="sessioncgi">sessioncgi</a>
hook(type => "sessioncgi", id => "foo", call => \&sessioncgi);
object and a session object. To check if the user is in fact signed in, you
can check if the session object has a "name" parameter set.
-### canedit
+### <a name="canedit">canedit</a>
hook(type => "canedit", id => "foo", call => \&canedit);
but is passed the named parameters `cgi` (a CGI object), `session` (a
session object), `src`, `srcfile`, `dest` and `destfile`.
-### checkcontent
+### <a name="checkcontent">checkcontent</a>
hook(type => "checkcontent", id => "foo", call => \&checkcontent);
that can be run to perform whatever action is necessary to allow the user
to post the content.
-### editcontent
+### <a name="editcontent">editcontent</a>
hook(type => "editcontent", id => "foo", call => \&editcontent);
It can modify the content as desired, and should return the content.
-### formbuilder
+### <a name="formbuilder">formbuilder</a>
hook(type => "formbuilder_setup", id => "foo", call => \&formbuilder_setup);
hook(type => "formbuilder", id => "foo", call => \&formbuilder);
strictly required.
* `section` can optionally specify which section in the config file
the plugin fits in. The convention is to name the sections the
- same as the tags used for [[plugins|plugin]] on this wiki.
+ same as the tags used for [[plugins]] on this wiki.
### genwrapper
The `%wikistate` hash can be used by a plugin to store persistant state
that is not bound to any one page. To set a value, use
-`$wikistate{$id}{$key}=$value, where `$value` is anything Storable can
+`$wikistate{$id}{$key}=$value`, where `$value` is anything Storable can
serialize, `$key` is any string you like, and `$id` must be the same as the
"id" parameter passed to `hook()` when registering the plugin, so that the
state can be dropped if the plugin is no longer used.
This hook and `rcs_preprevert` are optional, if not implemented, no revert
web interface will be available.
+### `rcs_find_changes($)`
+
+Finds changes committed since the passed RCS-specific rev. Returns
+a hash of the files changed, a hash of the files deleted, and the
+current rev.
+
+This hook is optional.
+
+### `rcs_get_current_rev()`
+
+Gets a RCS-specific rev, which can later be passed to `rcs_find_changes`.
+
+This hook is optional.
+
### PageSpec plugins
It's also possible to write plugins that add new functions to