package App::Termcast;
use Moose;
# ABSTRACT: broadcast your terminal sessions for remote viewing
with 'MooseX::Getopt::Dashes';
use IO::Pty::Easy;
use IO::Socket::INET;
use Scope::Guard;
use Term::ReadKey;
use JSON;
=head1 SYNOPSIS
my $tc = App::Termcast->new(user => 'foo');
$tc->run('bash');
=head1 DESCRIPTION
App::Termcast is a client for the L service, which allows
broadcasting of a terminal session for remote viewing.
=cut
=attr host
Server to connect to (defaults to noway.ratry.ru, the host for the termcast.org
service).
=cut
has host => (
is => 'rw',
isa => 'Str',
default => 'noway.ratry.ru',
documentation => 'Hostname of the termcast server to connect to',
);
=attr port
Port to use on the termcast server (defaults to 31337).
=cut
has port => (
is => 'rw',
isa => 'Int',
default => 31337,
documentation => 'Port to connect to on the termcast server',
);
=attr user
Username to use (defaults to the local username).
=cut
has user => (
is => 'rw',
isa => 'Str',
default => sub { $ENV{USER} },
documentation => 'Username for the termcast server',
);
=attr password
Password for the given user. The password is set the first time that username
connects, and must be the same every subsequent time. It is sent in plaintext
as part of the connection process, so don't use an important password here.
Defaults to 'asdf' since really, a password isn't all that important unless
you're worried about being impersonated.
=cut
has password => (
is => 'rw',
isa => 'Str',
default => 'asdf', # really unimportant
documentation => "Password for the termcast server\n"
. " (mostly unimportant)",
);
=attr bell_on_watcher
Whether or not to send a bell to the terminal when a watcher connects or
disconnects. Defaults to false.
=cut
has bell_on_watcher => (
is => 'rw',
isa => 'Bool',
default => 0,
documentation => "Send a terminal bell when a watcher connects\n"
. " or disconnects",
);
=attr timeout
How long in seconds to use for the timeout to the termcast server. Defaults to
5.
=cut
has timeout => (
is => 'rw',
isa => 'Int',
default => 5,
documentation => "Timeout length for the connection to the termcast server",
);
has _got_winch => (
traits => ['NoGetopt'],
is => 'rw',
isa => 'Bool',
default => 0,
init_arg => undef,
);
has establishment_message => (
traits => ['NoGetopt'],
is => 'ro',
isa => 'Str',
lazy_build => 1,
);
sub _build_establishment_message {
my $self = shift;
return sprintf("hello %s %s\n", $self->user, $self->password);
}
has socket => (
traits => ['NoGetopt'],
is => 'rw',
isa => 'IO::Socket::INET',
lazy_build => 1,
init_arg => undef,
);
sub _form_metadata_string {
my $self = shift;
my %data = @_;
my $json = JSON::encode_json(\%data);
return "\e[H\x00$json\xff\e[H\e[2J";
}
sub _build_socket {
my $self = shift;
my $socket;
{
$socket = IO::Socket::INET->new(PeerAddr => $self->host,
PeerPort => $self->port);
if (!$socket) {
Carp::carp "Couldn't connect to " . $self->host . ": $!";
sleep 5;
redo;
}
}
my ($cols, $lines) = GetTerminalSize();
my $resize_string = $self->_form_metadata_string(
geometry => [ $cols, $lines ],
);
$socket->syswrite($self->establishment_message);
select undef, undef, undef, 0.1; # XXX yuck :)
# this is going away once I move
# auth to on_data in ::Server
# instead of on_connect or whatever
# - jasonmay
$socket->syswrite($resize_string);
# ensure the server accepted our connection info
# can't use _build_select_args, since that would cause recursion
{
my ($rin, $ein, $rout, $eout) = ('') x 4;
vec($rin, fileno($socket), 1) = 1;
vec($ein, fileno($socket), 1) = 1;
my $res = select($rout = $rin, undef, $eout = $ein, undef);
redo if ($!{EAGAIN} || $!{EINTR}) && $res == -1;
if (vec($eout, fileno($socket), 1)) {
Carp::croak("Invalid password");
}
elsif (vec($rout, fileno($socket), 1)) {
my $buf;
$socket->recv($buf, 4096);
if (!defined $buf || length $buf == 0) {
Carp::croak("Invalid password");
}
elsif ($buf ne ('hello, ' . $self->user . "\n")) {
Carp::carp("Unknown login response from server: $buf");
}
}
}
ReadMode 5 if $self->_raw_mode;
return $socket;
}
before clear_socket => sub {
my $self = shift;
Carp::carp("Lost connection to server ($!), reconnecting...");
ReadMode 0 if $self->_raw_mode;
};
sub new_socket {
my $self = shift;
$self->clear_socket;
$self->socket;
}
has pty => (
traits => ['NoGetopt'],
is => 'rw',
isa => 'IO::Pty::Easy',
lazy_build => 1,
init_arg => undef,
);
sub _build_pty {
IO::Pty::Easy->new(raw => 0);
}
has _raw_mode => (
traits => ['NoGetopt'],
is => 'rw',
isa => 'Bool',
default => 0,
trigger => sub {
my $self = shift;
my ($val) = @_;
if ($val) {
ReadMode 5;
}
else {
ReadMode 0;
}
},
);
sub _build_select_args {
my $self = shift;
my @for = @_ ? @_ : (qw(socket pty input));
my %for = map { $_ => 1 } @for;
my ($rin, $win, $ein) = ('', '', '');
if ($for{socket}) {
my $sockfd = fileno($self->socket);
vec($rin, $sockfd, 1) = 1;
vec($win, $sockfd, 1) = 1;
vec($ein, $sockfd, 1) = 1;
}
if ($for{pty}) {
my $ptyfd = fileno($self->pty);
vec($rin, $ptyfd, 1) = 1;
}
if ($for{input}) {
my $infd = fileno(STDIN);
vec($rin, $infd ,1) = 1;
}
return ($rin, $win, $ein);
}
sub _socket_ready {
my $self = shift;
my ($vec) = @_;
vec($vec, fileno($self->socket), 1);
}
sub _pty_ready {
my $self = shift;
my ($vec) = @_;
vec($vec, fileno($self->pty), 1);
}
sub _in_ready {
my $self = shift;
my ($vec) = @_;
vec($vec, fileno(STDIN), 1);
}
=method write_to_termcast $BUF
Sends C<$BUF> to the termcast server.
=cut
sub write_to_termcast {
my $self = shift;
my ($buf) = @_;
my ($rin, $win, $ein) = $self->_build_select_args('socket');
my ($rout, $wout, $eout);
my $ready = select(undef, $wout = $win, $eout = $ein, $self->timeout);
if (!$ready || $self->_socket_ready($eout)) {
$self->clear_socket;
return $self->write_to_termcast(@_);
}
$self->socket->syswrite($buf);
}
=method run @ARGV
Runs the given command in the local terminal as though via C, but streams
all output from that command to the termcast server. The command may be an
interactive program (in fact, this is the most useful case).
=cut
sub run {
my $self = shift;
my @cmd = @_;
$self->socket;
$self->_raw_mode(1);
my $guard = Scope::Guard->new(sub { $self->_raw_mode(0) });
$self->pty->spawn(@cmd) || die "Couldn't spawn @cmd: $!";
local $SIG{WINCH} = sub {
$self->_got_winch(1);
$self->pty->slave->clone_winsize_from(\*STDIN);
$self->pty->kill('WINCH', 1);
syswrite STDOUT, "\e[H\e[2J"; # for the sake of sending a
# clear to the client anyway
my ($cols, $lines) = GetTerminalSize();
my $resize_string = $self->_form_metadata_string(
geometry => [$cols, $lines],
);
syswrite $self->socket, $resize_string;
};
while (1) {
my ($rin, $win, $ein) = $self->_build_select_args;
my ($rout, $wout, $eout);
my $select_res = select($rout = $rin, undef, $eout = $ein, undef);
my $again = $!{EAGAIN} || $!{EINTR};
if (($select_res == -1 && $again) || $self->_got_winch) {
$self->_got_winch(0);
redo;
}
if ($self->_socket_ready($eout)) {
$self->new_socket;
}
if ($self->_in_ready($rout)) {
my $buf;
sysread STDIN, $buf, 4096;
if (!defined $buf || length $buf == 0) {
Carp::croak("Error reading from stdin: $!")
unless defined $buf;
last;
}
$self->pty->write($buf);
}
if ($self->_pty_ready($rout)) {
my $buf = $self->pty->read(0);
if (!defined $buf || length $buf == 0) {
Carp::croak("Error reading from pty: $!")
unless defined $buf;
last;
}
syswrite STDOUT, $buf;
$self->write_to_termcast($buf);
}
if ($self->_socket_ready($rout)) {
my $buf;
$self->socket->recv($buf, 4096);
if (!defined $buf || length $buf == 0) {
if (defined $buf) {
$self->new_socket;
}
else {
Carp::croak("Error reading from socket: $!");
}
}
if ($self->bell_on_watcher) {
# something better to do here?
syswrite STDOUT, "\a";
}
}
}
}
__PACKAGE__->meta->make_immutable;
no Moose;
=head1 TODO
Use L to make configuration easier.
=head1 SEE ALSO
L
=cut
1;