WikiPatches/LastModifiedHeader

This patch sets the Last-Modified header on the page. ex. Last-Modified: Thu, 20 Jan 2005 07:11:33 GMT

Next time the browser requests the same page it will add a header to the request: If-Modified-Since: Thu, 20 Jan 2005 07:11:33 GMT

Given such a request usemod still produces the entire response, but my apache server (default) config catches that and converts the response into just: HTTP/1.x 304 Not Modified Date: Wed, 02 Feb 2005 00:58:17 GMT

- which obviously can save a lot of bandwidth. I verified this with the excellent http://livehttpheaders.mozdev.org/ plugin for FireFox?

I hope this will make it into the next version of UseMod. Regards, Lasse Lindgård

Change the GetHttpHeader method to this version:

sub GetHttpHeader {

  my ($type) = @_;
  my $cookie;
  my $lastmod;

  $type = 'text/html'  if ($type eq '');
  $lastmod = localtime($Section{'ts'});
  if (defined($SetCookie{'id'})) {
    $cookie = "$CookieName?="
            . "rev&" . $SetCookie{'rev'}
            . "&id&" . $SetCookie{'id'}
            . "&randkey&" . $SetCookie{'randkey'};
    $cookie .= ";expires=Fri, 08-Sep-2013 19:48:23 GMT";
    if ($HttpCharset ne '') {
      return $q->header(-cookie=>$cookie,
                        -type=>"$type; charset=$HttpCharset", "Last-Modified"=>$lastmod);
    }
    return $q->header(-cookie=>$cookie, "Last-Modified"=>$lastmod);
  }
  if ($HttpCharset ne '') {
    return $q->header(-type=>"$type; charset=$HttpCharset", "Last-Modified"=>$lastmod);
  }
  return $q->header(-type=>$type, "Last-Modified"=>$lastmod);

}

NOTE: I havn't done extensive testing on how this works with special pages. It doesn't cache RecentChanges though ...

• Here's what happened after trying this patch. Went to edit a page, preview worked fine, saved the page and saw the previous version. The new version showed up after reloading the page. Went to edit this new version and saw the old version in the edit box! Had to reload again...