pubsub.pl

use Mojolicious::Lite;
use Mojo::Pg;

helper pg =>
  sub { state $pg = Mojo::Pg->new('postgresql://tester:testing@/test') };

get '/' => sub {
  my $c = shift;

  my $address = $c->tx->remote_address;
  my $port    = $c->tx->remote_port;

  $c->inactivity_timeout(300);

  my $cb = $c->pg->pubsub->listen(visitors => sub {
    my ($pubsub, $visitor) = @_;
    $c->write($visitor);
  });
  $c->pg->pubsub->notify(visitors => "$address:$port");

  $c->on(finish => sub { shift->pg->pubsub->unlisten(visitors => $cb) });
};

app->start;