#!/usr/bin/perl
use strict;
use warnings;
use Socket;
use IO::Async::Loop;
use IO::Async::Stream;
use IO::Socket;
use Time::HiRes qw(usleep);

# standard event loop
my $loop = IO::Async::Loop->new;

# notification service socket connection; we only write outgoing
my $NOTIFY = IO::Socket::INET->new(
    PeerHost => $a_local_network_host,
    PeerPort => $comm_port,
    Proto => 'tcp',
    Type => SOCK_STREAM,
    ReuseAddr => 1,
    Blocking => 0
) or warn("Can't connect to NOTIFY: $!\n");
setsockopt($NOTIFY, SOL_SOCKET, SO_KEEPALIVE, 1);

# main interface element via IO::Async
my $notifystream = IO::Async::Stream->new(
    handle => $NOTIFY,
    on_read => sub {
        my ( $self, $buffref, $eof ) = @_;
        # here's where we need to handle $eof if the remote goes away
        if($eof) {
            # i have tried several things here
            usleep(200000); # give the remote service some milliseconds to start back up
            # process fails if remote is not back up, so i know the timeout is 'good enough' for this test
            # attempt to reconnect.  have also tried recreating from scratch
            $NOTIFY->connect("$a_local_network_host:$comm_port");
            # this doesn't seem to have any effect
            $self->configure(handle=>$NOTIFY);
        }
    }
);
$loop->add( $notifystream );

# kickstart the event loop
$loop->run;

### -- Meanwhile, elsewhere in the code -- ###

$notifystream->write("data for notification service\n");