ikiwiki/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;
    }

    1