I do something similar to what you are asking using mason's cache as a flag to say it's being built. 
my $page = $m->dhandler_arg;
# do sanity checking ...
unless ($m->comp_exists($page)) {
  unless ($m->cache->get($page)) { # see if we're building it already
    $m->cache->set($page,'1','60 sec'); # set a flag to say we're buil
+ding it
    $m->comp("/building_page"); # please wait page
    $m->flush_buffer; # flush the output
    # here we begin building the page
    $m->comp("/build_page", $page);
  }
  $m->comp("/building_page");
  $m->flush_buffer;
}
</%init>

[download]

The building page, would spit up a simple note saying it's processing, and a meta-refresh tag so the client re-requests it in a moment. A little css/javascript can be used to add some animation to keep them amused.

(code above is untested, but should get you going in the right direction)

In reply to Re: Mason: Please Wait While Generating by cowboy
in thread Mason: Please Wait While Generating by water

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