Revert "added hook urlpath" and "rename urlpath hook into tweakurlpath..."

[ikiwiki.git] / doc / plugins / write.mdwn

diff --git a/doc/plugins/write.mdwn b/doc/plugins/write.mdwn
index daf70c8e23393d5b860b30e324523da6f46c45ab..e8ac9614b4335cd6203853473e289c2c1b8a5115 100644 (file)
--- a/doc/plugins/write.mdwn
+++ b/doc/plugins/write.mdwn
@@ -196,7 +196,6 @@ generating the page.
 
        hook(type => "pagetemplate", id => "foo", call => \&pagetemplate);
 
-
 [[Templates|wikitemplates]] are filled out for many different things in
 ikiwiki, like generating a page, or part of a blog page, or an rss feed, or
 a cgi. This hook allows modifying the variables available on those
@@ -428,6 +427,15 @@ describes the plugin as a whole. For example:
   and undef if a rebuild could be needed in some circumstances, but is not
   strictly required.
 
+### targetpage
+
+       hook(type => "targetpage", id => "foo", call => \&targetpage);
+
+This hook can be used to override the name of the file a page should
+be compiled into. 
+
+It should return the target filename.
+
 ## Plugin interface
 
 To import the ikiwiki plugin interface:
@@ -821,6 +829,30 @@ it up in the history.
 
 It's ok if this is not implemented, and throws an error.
 
+#### `rcs_receive()`
+
+This is called when ikiwiki is running as a pre-receive hook (or
+equivalent), and is testing if changes pushed into the RCS from an
+untrusted user should be accepted. This is optional, and doesn't make
+sense to implement for all RCSs.
+
+It should examine the incoming changes, and do any sanity 
+checks that are appropriate for the RCS to limit changes to safe file adds,
+removes, and changes. If something bad is found, it should exit
+nonzero, to abort the push. Otherwise, it should return a list of
+files that were changed, in the form:
+
+       {
+               file => # name of file that was changed
+               action => # either "add", "change", or "remove"
+               path => # temp file containing the new file content, only
+                       # needed for "add"/"change", and only if the file
+                       # is an attachment, not a page
+       }
+
+The list will then be checked to make sure that each change is one that
+is allowed to be made via the web interface.
+
 ### PageSpec plugins
 
 It's also possible to write plugins that add new functions to
@@ -848,6 +880,56 @@ By the way, to parse a ikiwiki setup file and populate `%config`, a
 program just needs to do something like:
 `use IkiWiki::Setup; IkiWiki::Setup::load($filename)`
 
+### Function overriding
+
+Sometimes using ikiwiki's pre-defined hooks is not enough. Your plugin
+may need to replace one of ikiwiki's own functions with a modified version,
+or wrap one of the functions.
+
+For example, your plugin might want to override `displaytime`, to change
+the html markup used when displaying a date. Or it might want to override
+`IkiWiki::formattime`, to change how a date is formatted. Or perhaps you
+want to override `bestlink` and change how ikiwiki deals with WikiLinks.
+
+By venturing into this territory, your plugin is becoming tightly tied to
+ikiwiki's internals. And it might break if those internals change. But
+don't let that stop you, if you're brave.
+
+Ikiwiki provides an `inject()` function, that is a powerful way to replace
+any function with one of your own. This even allows you to inject a
+replacement for an exported function, like `bestlink`. Everything that
+imports that function will get your version instead. Pass it the name of
+the function to replace, and a new function to call. 
+
+For example, here's how to replace `displaytime` with a version using HTML 5
+markup:
+
+       inject(name => 'IkiWiki::displaytime', call => sub {
+               return "<time>".formattime(@_)."</time>";
+       });
+
+Here's how to wrap `bestlink` with a version that tries to handle
+plural words:
+
+       my $origbestlink=\&bestlink;
+       inject(name => 'IkiWiki::bestlink', call => \&mybestlink);
+
+       sub deplural ($) {
+               my $word=shift;
+               $word =~ s/e?s$//; # just an example :-)
+               return $word;
+       }
+
+       sub mybestlink ($$) {
+               my $page=shift;
+               my $link=shift;
+               my $ret=$origbestlink->($page, $link);
+               if (! length $ret) {
+                       $ret=$origbestlink->($page, deplural($link));
+               }
+               return $ret;
+       }
+
 ### Javascript
 
 Some plugins use javascript to make ikiwiki look a bit more web-2.0-ish.