in reply to Mojolicious websocket question

thanks for the replies - here's an example of a Mojolicious::Lite app that is not working for me. This is based on the examples I mentioned, but likley I'm the one who broke it, of course: 

#!/usr/bin/perl
use Mojolicious::Lite;
use ZMQ;
use ZMQ::Constants qw|ZMQ_PUB ZMQ_SUB ZMQ_SUBSCRIBE ZMQ_FD ZMQ_DONTWAI
+T ZMQ_NOBLOCK|;
use strict;

# Template with browser-side code
get '/' => 'index';

# WebSocket echo service
websocket '/msgs' => sub {
  my $c = shift;

  # Opened
  $c->app->log->debug('WebSocket opened');
  # Increase inactivity timeout for connection a bit
  $c->inactivity_timeout(300);

  my $ctx  = ZMQ::Context->new(10);
  my $subsocket = $ctx->socket(ZMQ_SUB);
  $subsocket->setsockopt(ZMQ_SUBSCRIBE,'event');
  $subsocket->connect   ('tcp://127.0.0.1:5555');
  my $subsocket_fd = IO::Handle->new_from_fd($subsocket->getsockopt(ZM
+Q_FD),'r');
  Mojo::IOLoop->singleton->reactor->io($subsocket_fd=>
    sub {
     my ( $r, $w ) = @_;
      if (my $message = $subsocket->recvmsg(ZMQ_DONTWAIT)) {
        $c->send($message->data);
      }
      undef $w;
    }
  );
  Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
};


app->start;


__DATA__

@@ index.html.ep
<!DOCTYPE html>
<html>
  <head><title>Echo</title></head>
  <body>
    <script>
      var ws = new WebSocket('<%= url_for('msgs')->to_abs %>');
      ws.onmessage = function (msg) {
        document.body.innerHTML += msg.data + '<br/>';
      };
    </script>
msgs<br>  </body>
</html>

[download]
when I run this with morbo, it starts up fine, but when I access it with the web browser, I get:

Assertion failed: pfd.revents & POLLIN (signaler.cpp:242)

in the console, and the browser complains that

WebSocket connection to 'ws://myserver:3000/msgs' failed: Connection closed before receiving a handshake response

I've tried a bunch of variations of this, putting the IO loop in different places, using AnyEvent instead of Mojo::IOLoop, using ZMQ::FFI instead of ZMQ, etc., but all essentially with the same result.

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