I would quite like the ability to write a page (blog post in practice) but for the page to not be displayed until a date and time after it is added to the wiki. I've thought this through a bit, but would appreciate feedback from people before I go any further. Would anyone else find this useful?

Thinking about how to implement this in ikiwiki, perhaps a conditional pagespec would be best (which could be tidied up into a template)

[[!if  test="current_date_before(<TMPL_VAR date>)"
then="""[[!tag draft]]"""
else="""[[!meta date="<TMPL_VAR date>"]]"""

…pre-supposing a scheme whereby tagging 'draft' hides the page from an aggregation somewhere. With a template, this could collapse to

[[!template  id=publishafter date="Thu Aug 30 14:13:06 BST 2012"]]

This would require implementing the current_date_before pagespec.

You would also need a regularly scheduled wiki refresh and a way of marking the unpublished pages as 'dirty' so they were always scanned on refresh until their publish date has occurred. That could perhaps be implemented via a small plugin which defined a pagespec which ensured the page was 'dirty':

[[!meta  date="<TMPL_VAR date>"]]
[[!if  test="!current_date_before(<TMPL_VAR date>)"
then="""[[!tag draft]][[!dirty]]"""

The following is an attempt at the dirty part:

package IkiWiki::Plugin::dirty;
# provides a pagespec 'dirty' which ensures the page will always be
# re-scanned for content on wiki refresh.

use warnings;
use strict;
use IkiWiki 3.00;

hook(type => "preprocess", id => "dirty", call => \&preprocess);
hook(type => "needsbuild", id => "dirty", call => \&needsbuild);

sub preprocess (@) {
  my %params = @_;
  $pagestate{$params{page}}{dirty}{dirty} = 1;
  return '';

sub needsbuild (@) {
  my $pages= shift;
  my %p2 = map { $_ => 1 } @$pages;
  my %d2 = map { $_ => 1 } @$deleted;

  foreach my $page (keys %pagestate) {
    if(exists $pagestate{$page}{dirty}{dirty}) {
      push @$pages, $pagesources{$page} unless
        (exists $p2{$pagesources{$page}} or exists $d2{$pagesources{$page}});
      delete $pagestate{$page}{dirty}{dirty};

  return $pages;


Although it doesn't fit, the current_date_before pagespec could be implemented in the same plugin. I tried the following (before the trailing 1):

package IkiWiki::PageSpec;
use Date::Parse;

sub match_current_date_before ($$;@) {
  my $date = shift;
  my $out = str2time($date);
  if(defined $out) {
    return IkiWiki::SuccessReason->new("time before now") if $out < time();
    return IkiWiki::FailReason->new("time not before now");
  } else { return IkiWiki::ErrorReason->new("couldn't parse time $date")};

I always hit the ErrorReason branch when I try to use it, even with strings which work fine in test scripts. If anyone can help me debug that I'd be very grateful. If anyone has any clues as to why this doesn't work

Thoughts on the whole idea? — Jon

There is an old todo about it: tagging with a publication date. I feel my idea there about making a pagespec that is limited to items in the present/past, combined with setting the meta data, is a good way.. --Joey

Thanks for your response Joey. Should I merge these two TODOs, then? So if I understand you correctly, you would prefer some new pagespecs to match future/past dates, and a plugin which kept track of pages with a future date and kept them 'dirty' (similar to the above), which means avoiding the need for a dirty pagespec in the page itself. Is that about right?

I came up with the following, but I haven't adapted dirty.pm inline with my understanding above, yet.

sub match_infuture ($$;@) {
  my $page = shift;
  return IkiWiki::SuccessReason->new("page time is in the future")
    if $IkiWiki::pagectime{$page} > time;
  return IkiWiki::FailReason->new("page time is not in the future");

I've managed to get my original suggestion working. The problem was I was using quotes when invoking the pagespec, which stopped str2time working.

Let me know if I've understood your POV correctly and I'll see about tidying this up and putting it in a branch.

Finally, a way of scheduling future runs of ikiwiki within ikiwiki itself might be useful for other things too, and would avoid the need for a cron job in this case. (I'm thinking of a plugin that implemented itself in terms of cron, or at, or both, or possibly other things depending on what people want to support). But that would be substantially more work, more than I can afford atm at least. — Jon

Some times ago, I wrote a Pagespec function that matches pages that have creation date in the future: created in future. It can be enhanced to create the current_date_before(<DATE>) pagespec. The interesting part of my plugin is that it makes IkiWiki rebuild pages on the right date.

-- Louis