How to write a client program for Net::WebSocket::Server program? - perl

Question

I have a server program that listens on 9000 port. But I can't find a way to write a client program for that server that connects server at 9000 port. Here is the main part of server program:
use strict;
use warnings;
use Net::WebSocket::Server;
my $port = "9000";
my $msg_count = 0;
print "starting server on $port \n\n";
my $count = 2400;
Net::WebSocket::Server->new(
listen => $port,
silence_max => 5,
tick_period => 300,
on_tick => sub {
my ($serv) = #_;
print "connections >> " . $serv->connections . "\n";
print $_->ip() for( $serv->connections() ); print "\n";
print $_->port() for( $serv->connections() ); print "\n\n";
$count++;
},
on_connect => sub {
my ($serv, $conn) = #_;
$conn->on(
handshake => sub {
my ($conn, $handshake) = #_;
my $tmp = $handshake->req->origin;
print "here ... $tmp \n\n";
},
utf8 => sub {
my ($conn, $msg) = #_;
my $IP = $conn->ip();
my $PORT = $conn->port();
my $SERVER = $conn->server();
my $SOCKET = $conn->socket();
my $str = Dumper $SOCKET;
I searched internet and what that sounds understandable to me is the following client program:
use strict;
use warnings;
use IO::Socket::SSL;
my $cl=IO::Socket::SSL->new("http://localhost:9000") or die "error=$!, ssl_error=$SSL_ERROR";
if($cl) {
$cl->connect_SSL or die $#;
# Something about certificates?
$cl->syswrite("Command");
close($cl);
}
But its not working. The error client program generates is as follows:
Expected 'PeerService' at client2.pl line 5.
I am newbie in Socket programming and currently understanding websockets programming in Perl.
Note: I am on windows platform.
I ran the example code suggested https://stackoverflow.com/questions/37318581/simple-perl-websocket-client. It gives error "Can't use an undefined value as a subroutine reference at C:/Strawberry/perl/site/lib/Protocol/WebSocket/Client.pm line 103.":
use strict;
use warnings;
use Protocol::WebSocket::Client;
my $client = Protocol::WebSocket::Client->new(url => 'ws://localhost:9000') or die "$!";
my $reply = "Free\n";
# Sends a correct handshake header
$client->connect or die "$!";
# Register on connect handler
$client->on(
connect => sub {
$client->write('hi there');
}
) or die "$!";
# Parses incoming data and on every frame calls on_read
$client->read($reply);
print "$reply\n";
# Sends correct close header
$client->disconnect;

Answer 1

Please investigate following demo code snippets for WebSocket Server and Client.
Note: please do not forget to alter code to match your server origin (ip address and port)
use strict;
use warnings;
use feature 'say';
use Net::WebSocket::Server;
my $origin = 'http://192.168.1.160:8080'; # server origin
my $port = 8080;
$| = 1;
say "Starting server on $port";
Net::WebSocket::Server->new(
listen => $port,
tick_period => 60,
on_tick => sub {
my ($serv) = #_;
my $stamp = 'Server time: ' . scalar localtime;
$_->send_utf8($stamp) for $serv->connections;
},
on_connect => sub {
my ($serv, $conn) = #_;
$conn->on(
handshake => sub {
my ($conn, $handshake) = #_;
$conn->disconnect() unless $handshake->req->origin eq $origin;
},
ready => sub {
my ($conn) = #_;
say "Client: connect IP $conn->{ip} PORT $conn->{port}";
my $msg = 'Connected server time is ' . scalar localtime . "\n";
$_->send_utf8($msg) for $conn->server->connections;
},
utf8 => sub {
my ($conn, $msg) = #_;
say "Client message: $conn->{ip} $msg";
$_->send_utf8('Server reply: ' . $msg)
for $conn->server->connections;
$conn->disconnect() if $msg eq 'exit';
},
binary => sub {
my ($conn, $msg) = #_;
$_->send_binary($msg) for $conn->server->connections;
},
pong => sub {
my ($conn, $msg) = #_;
$_->send_utf8($msg) for $conn->server->connections;
},
disconnect => sub {
my ($conn, $code, $reason) = #_;
say "Client: disconnect IP $conn->{ip} PORT $conn->{port}";
},
);
},
)->start;
Client
use strict;
use warnings;
use feature 'say';
use IO::Async::Loop;
use Net::Async::WebSocket::Client;
my $HOST = '192.168.1.160';
my $PORT = 8080;
my $loop = IO::Async::Loop->new;
my $client = Net::Async::WebSocket::Client->new(
on_text_frame => sub {
my ( $self, $frame ) = #_;
say $frame;
},
);
my $input = IO::Async::Stream->new_for_stdin(
on_read => sub {
my ( $self, $buffref, $eof ) = #_;
my $msg;
$msg = $1 while $$buffref =~ s/^(.*)\n//;
$client->send_text_frame( $msg );
$loop->loop_stop if $msg eq 'exit';
return 0;
},
);
$loop->add( $client );
$loop->add( $input );
$client->connect(
url => "ws://$HOST:$PORT/"
)->then( sub {
say 'Successfully connected to server';
$client->send_text_frame( scalar localtime );
})->get;
$loop->run;
say 'Bye, until next time';
exit 0;
References:
Net::WebSocket::Server
Net::Async::WebSocket::Client
IO::Async::Loop