doc/todo/tmplvars_plugin.mdwn



A simple plugin to allow per-page customization of a template by passing paramaters to HTML::Template. For those times when a whole pagetemplate is too much work. --Ethan
[[!tag patch]]

The implementation looks fine to me (assuming it works with current ikiwiki),
apart from the "XXX" already noted in the patch. The design could reasonably
be considered premature generalization, though - how often do you actually
need to define new tmplvars?
As for the page/destpage/preview thing, it would be good if the preprocess
hook could distinguish between software-supplied and user-supplied
parameters (the [[plugins/tag]] plugin could benefit from this too). Perhaps
the IkiWiki core could be modified so that
hook(type => "preprocess", splitparams => 1, ...) would invoke preprocess
with { page => "foo", destpage => "bar", ... } as a special first argument,
and the user-supplied parameters as subsequent arguments? Then plugins like
tag could use:
my $ikiparams = shift;
my %params = @_;

add_tags($ikiparams->{page}, keys %params);

--[[smcv]]


#!/usr/bin/perl
package IkiWiki::Plugin::tmplvars;

use warnings;
use strict;
use IkiWiki 2.00;

my %tmplvars;

sub import {
    hook(type => "preprocess", id => "tmplvars", call => \&preprocess);
    hook(type => "pagetemplate", id => "tmplvars", call => \&pagetemplate);
}

sub preprocess (@) {
    my %params=@_;

    if ($params{page} eq $params{destpage}) {
	    my $page = $params{page};
	    if (undef $tmplvars{$page}){
		    $tmplvars{$page} = {};
	    }
	    # XXX: The only way to get at just the user-specified params is
	    # to try to remove all the Ikiwiki-supplied ones.
	    delete $params{page};
	    delete $params{destpage};
	    delete $params{preview};
	    foreach my $arg (keys %params){
		    $tmplvars{$page}->{$arg} = $params{$arg};
	    }
    }

}

sub pagetemplate (@) {
        my %params=@_;
        my $template = $params{template};

        if (exists $tmplvars{$params{page}}) {
                foreach my $arg (keys %{$tmplvars{$params{page}}}){
                        $template->param($arg => $tmplvars{$params{page}}->{$arg});
                }
        }

        return undef;
}

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