I'm trying to create a new route in dancer that will serve as a proxy of sorts to another service. This other service returns various kinds of files of varying size.

For small files, the following snippet works fine:

  my $ua = LWP::UserAgent->new(timeout => 180,);
  $ua->env_proxy;

  my $rsp = $ua->head($new_route);
  send_error('Bad Gateway (head)', 502) unless (ref $rsp && $rsp->is_s
+uccess);

  foreach my $key ('Content-Encoding', 'Content-Length', 'Content-Type
+', 'Last-Modified') {
      my $value = $rsp->header($key) || '';
      header($key => $value) if ($value);
  }

  $rsp = $ua->get($new_route);
  send_error('Bad Gateway (get)', 502) unless (ref $rsp && $rsp->is_su
+ccess);
  return $rsp->content;

[download]

The problem that I'm having is that, for large files, I would like to be able to stream the response. Now LWP::UserAgent allows for grabbing the response in chunks using a callback and Dancer allows sending data in chunks using send_file with a callback but I (as yet) have no clue how to tie the two together in any workable fashion.

Any ideas how to make this work?

In reply to Dancer as a proxy by gsiems

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