Websocket not always keeping Close promise

[rbt]

Websocket Close Promise doesn't fire during abnormal closures. A poorly configured firewall lead me to finding out that timed-out connections were not being cleaned up.

The below script simply sets up a socket and tells the user to run ss --kill in another session. This isn't exactly the same as the firewall timeout, but it does demonstrates the same issue.

I do get a "software caused connection abort" message which seems to originate from libuv. A connection timeout doesn't print a message in the terminal.

CRO_TRACE=1 indicates many components receive a DONE event.

use Cro::HTTP::Router;
use Cro::HTTP::Router::WebSocket;
use Cro::HTTP::Server;
use Cro::WebSocket::Client;

my $http-request;
my $application = route {
  get -> 'websocket' {
    $http-request = request;

    web-socket -> $incoming, $close {
      supply {
        whenever $incoming -> $msg {
           await($msg.body).say;
        }
        whenever $close {
           say "NEVER HERE";
        }
      }
    }
  }
}

my $cro-service = Cro::HTTP::Server.new(:http<1.1>, :host<0.0.0.0>, :port<10200>, :$application);
$cro-service.start;

{
    my $connection = await Cro::WebSocket::Client.connect: 'http://localhost:10200/websocket';
    $connection.send('Have Connection');
}

# Text will report "software caused connection abort" but $close will not fire.
say 'Run: sudo ss --kill dst %s/32 dport %s'.sprintf($http-request.connection.peer-host, $http-request.connection.peer-port);

react whenever signal(SIGINT) {
    $cro-service.stop;
    exit;
}