AnyEvent-MP/MP/DataConn.pm

=head1 NAME

AnyEvent::MP::DataConn - create socket connections between nodes

=head1 SYNOPSIS

   use AnyEvent::MP::DataConn;

=head1 DESCRIPTION

This module can be used to create socket connections between the local and
a remote node in the aemp network. The socket can be used freely for any
purpose, and in most cases, this mechanism is a good way to transport big
chunks of binary data.

The connections created by this module use the same security mechanisms
as normal AEMP connections (secure authentication, optional use of TLS),
and in fact, use the same listening port as AEMP connections, so when two
nodes can reach each other, they can, with high probability, creare a data
connection between them.

The protocol is, however, not the AEMP transport protocol, so this will
only work between nodes implementing the "aemp-dataconn" protocol.

=head1 FUNCTIONS

=over 4

=cut

package AnyEvent::MP::DataConn;

use common::sense;
use Carp ();
use POSIX ();

use AnyEvent ();
use AnyEvent::Util ();

use AnyEvent::MP;
use AnyEvent::MP::Kernel ();
use AnyEvent::MP::Global ();

our $ID = "a";
our %STATE;

sub _accept {
   my ($id, $timeout, $initspec) = @_;

   my $cleanup = sub {
      %{delete $STATE{$id}} = ();
   };

   $STATE{$id} = {
      id      => $id,
      to      => (AE::timer $timeout, 0, $cleanup),
      success => sub {
         my ($func, @args) = @$initspec;
         $cleanup->();
         (AnyEvent::MP::Kernel::load_func $func)->(@args, @_);
      },
      fail    => sub {
         $cleanup->();
         # nop?
      },
   };
}

sub _inject {
   my ($conn, $error) = @_;

   my $hdl = delete $conn->{hdl};
   die "inject <@_>\n";#d#
}

sub _connect {
   my ($id) = @_;

   my $state = $STATE{$id}
      or return;

   my $addr = $AnyEvent::MP::Global::addr{$state->{node}};

   @$addr
      or return $state->{fail}("$state->{node}: no listeners found");

   my %transport;

   # I love hardcoded constants
   $state->{next} = AE::timer 0, 2, sub {
      my $endpoint = shift @$addr
         or return delete $state->{next};

      my ($host, $port) = AnyEvent::Socket::parse_hostport $endpoint
         or return;

      my $transport; $transport = AnyEvent::MP::Transport::mp_connect
         $host, $port,
         protocol => "aemp-dataconn",
         sub { $transport->destroy },
      ;
   };
}

=item AnyEvent::MP::DataConn::connect_to $node, $timeout, [$initfunc, @initdata], $cb->($handle)

Creates a socket connection between the local node and the node C<$node>
(which can also be specified as a port).

When the connection could be successfully created, the C<$initfunc>
will be called with the given C<@initdata> on the remote node (similar
to C<snd_to_func> or C<spawn>), and the C<AnyEvent::Handle> object
representing the remote connection end as additional argument.

Also, the callback given as last argument will be called with the
AnyEvent::Handle object for the local side.

The AnyEvent::Handle objects will be in a "quiescent" state - you could rip
out the file handle and forget about it, but it is recommended to use it,
as the security settings might have called for a TLS connection. If you
opt to use it, you at least have to set an C<on_error> callback.

In case of any error (timeout etc.), nothing will be called on
the remote side, and the local port will be C<kil>'ed with an C<<
AnyEvent::MP::DataConn => "error message" >> kill reason.

=cut

sub connect_to($$$;@) {
   my ($node, $timeout, $initspec, @localmsg) = @_;
   my $port = $SELF;
   $node = node_of $node;

   my $id = (++$ID) . "\@$NODE";

   my $cleanup = sub {
      delete $AnyEvent::MP::Global::ON_SETUP{$id};
      %{delete $STATE{$id}} = ();
   };

   # damn, why do my simple state hashes resemble objects so quickly
   my $state = $STATE{$id} = {
      id       => (++$ID) . "\@$NODE",
      node     => $node,
      port     => $port,
      to       => (AE::timer $timeout, 0, sub {
         $cleanup->();
         kil $port, AnyEvent::MP::DataConn:: => "$node: unable to establish connection within $timeout seconds";
      }),
      success  => sub {
         $cleanup->();
         snd @localmsg, @_;
      },
      fail     => sub {
         $cleanup->();
         kil $port, AnyEvent::MP::DataConn:: => $_[0];
      },
   };

   if (AnyEvent::MP::Kernel::port_is_local $node) {
      return kil $port, AnyEvent::MP::DataConn:: =>
         "connect_to does not yet support local/local connections, please bug me about it";

   } else {
      AnyEvent::MP::Kernel::snd_to_func $node, AnyEvent::MP::DataConn::_accept:: => $id, $timeout, $initspec;

      $state->{wait} = sub {
         if (my $addr = $AnyEvent::MP::Global::addr{$node}) {
            delete $AnyEvent::MP::Global::ON_SETUP{$id};

         warn "<@_ @$addr $addr>\n";#d#
            # continue connect
            if (@$addr) {
               # node has listeners, so connect
               _connect $id;
            } else {
               # no listeners, ask it to connect to us
               AnyEvent::MP::Kernel::snd_to_func $node, AnyEvent::MP::DataConn::_connect:: => $id;
            }
         } else {
            # wait for the next global setup handshake
            $AnyEvent::MP::Global::ON_SETUP{$id} = $state->{wait};
         };
      };

      $state->{wait}->();
   }
}

=back

=head1 SEE ALSO

L<AnyEvent::MP>.

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://home.schmorp.de/

=cut

1

Revision:	1.2
Committed:	Sat Nov 7 02:36:31 2009 UTC (16 years, 10 months ago) by root
Branch:	MAIN
Changes since 1.1:	+111 -24 lines
Log Message:	bleh
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3			AnyEvent::MP::DataConn - create socket connections between nodes
4
5			=head1 SYNOPSIS
6
7			use AnyEvent::MP::DataConn;
8
9			=head1 DESCRIPTION
10
11			This module can be used to create socket connections between the local and
12			a remote node in the aemp network. The socket can be used freely for any
13			purpose, and in most cases, this mechanism is a good way to transport big
14			chunks of binary data.
15
16			The connections created by this module use the same security mechanisms
17			as normal AEMP connections (secure authentication, optional use of TLS),
18			and in fact, use the same listening port as AEMP connections, so when two
19			nodes can reach each other, they can, with high probability, creare a data
20			connection between them.
21
22			The protocol is, however, not the AEMP transport protocol, so this will
23			only work between nodes implementing the "aemp-dataconn" protocol.
24
25			=head1 FUNCTIONS
26
27			=over 4
28
29			=cut
30
31			package AnyEvent::MP::DataConn;
32
33			use common::sense;
34			use Carp ();
35			use POSIX ();
36
37			use AnyEvent ();
38			use AnyEvent::Util ();
39
40			use AnyEvent::MP;
41	root	1.2	use AnyEvent::MP::Kernel ();
42			use AnyEvent::MP::Global ();
43
44			our $ID = "a";
45			our %STATE;
46
47			sub _accept {
48			my ($id, $timeout, $initspec) = @_;
49
50			my $cleanup = sub {
51			%{delete $STATE{$id}} = ();
52			};
53
54			$STATE{$id} = {
55			id => $id,
56			to => (AE::timer $timeout, 0, $cleanup),
57			success => sub {
58			my ($func, @args) = @$initspec;
59			$cleanup->();
60			(AnyEvent::MP::Kernel::load_func $func)->(@args, @_);
61			},
62			fail => sub {
63			$cleanup->();
64			# nop?
65			},
66			};
67			}
68	root	1.1
69			sub _inject {
70			my ($conn, $error) = @_;
71	root	1.2
72			my $hdl = delete $conn->{hdl};
73			die "inject <@_>\n";#d#
74	root	1.1	}
75
76	root	1.2	sub _connect {
77			my ($id) = @_;
78
79			my $state = $STATE{$id}
80			or return;
81
82			my $addr = $AnyEvent::MP::Global::addr{$state->{node}};
83
84			@$addr
85			or return $state->{fail}("$state->{node}: no listeners found");
86
87			my %transport;
88
89			# I love hardcoded constants
90			$state->{next} = AE::timer 0, 2, sub {
91			my $endpoint = shift @$addr
92			or return delete $state->{next};
93
94			my ($host, $port) = AnyEvent::Socket::parse_hostport $endpoint
95			or return;
96
97			my $transport; $transport = AnyEvent::MP::Transport::mp_connect
98			$host, $port,
99			protocol => "aemp-dataconn",
100			sub { $transport->destroy },
101			;
102			};
103			}
104
105			=item AnyEvent::MP::DataConn::connect_to $node, $timeout, [$initfunc, @initdata], $cb->($handle)
106	root	1.1
107			Creates a socket connection between the local node and the node C<$node>
108			(which can also be specified as a port).
109
110			When the connection could be successfully created, the C<$initfunc>
111			will be called with the given C<@initdata> on the remote node (similar
112			to C<snd_to_func> or C<spawn>), and the C<AnyEvent::Handle> object
113	root	1.2	representing the remote connection end as additional argument.
114	root	1.1
115	root	1.2	Also, the callback given as last argument will be called with the
116			AnyEvent::Handle object for the local side.
117	root	1.1
118	root	1.2	The AnyEvent::Handle objects will be in a "quiescent" state - you could rip
119	root	1.1	out the file handle and forget about it, but it is recommended to use it,
120	root	1.2	as the security settings might have called for a TLS connection. If you
121	root	1.1	opt to use it, you at least have to set an C<on_error> callback.
122
123	root	1.2	In case of any error (timeout etc.), nothing will be called on
124			the remote side, and the local port will be C<kil>'ed with an C<<
125	root	1.1	AnyEvent::MP::DataConn => "error message" >> kill reason.
126
127			=cut
128
129			sub connect_to($$$;@) {
130			my ($node, $timeout, $initspec, @localmsg) = @_;
131			my $port = $SELF;
132			$node = node_of $node;
133
134	root	1.2	my $id = (++$ID) . "\@$NODE";
135	root	1.1
136	root	1.2	my $cleanup = sub {
137			delete $AnyEvent::MP::Global::ON_SETUP{$id};
138			%{delete $STATE{$id}} = ();
139	root	1.1	};
140
141	root	1.2	# damn, why do my simple state hashes resemble objects so quickly
142			my $state = $STATE{$id} = {
143			id => (++$ID) . "\@$NODE",
144			node => $node,
145			port => $port,
146			to => (AE::timer $timeout, 0, sub {
147			$cleanup->();
148			kil $port, AnyEvent::MP::DataConn:: => "$node: unable to establish connection within $timeout seconds";
149			}),
150			success => sub {
151			$cleanup->();
152			snd @localmsg, @_;
153			},
154			fail => sub {
155			$cleanup->();
156			kil $port, AnyEvent::MP::DataConn:: => $_[0];
157			},
158	root	1.1	};
159
160	root	1.2	if (AnyEvent::MP::Kernel::port_is_local $node) {
161	root	1.1	return kil $port, AnyEvent::MP::DataConn:: =>
162			"connect_to does not yet support local/local connections, please bug me about it";
163	root	1.2
164	root	1.1	} else {
165	root	1.2	AnyEvent::MP::Kernel::snd_to_func $node, AnyEvent::MP::DataConn::_accept:: => $id, $timeout, $initspec;
166
167			$state->{wait} = sub {
168			if (my $addr = $AnyEvent::MP::Global::addr{$node}) {
169			delete $AnyEvent::MP::Global::ON_SETUP{$id};
170
171			warn "<@_ @$addr $addr>\n";#d#
172			# continue connect
173			if (@$addr) {
174			# node has listeners, so connect
175			_connect $id;
176			} else {
177			# no listeners, ask it to connect to us
178			AnyEvent::MP::Kernel::snd_to_func $node, AnyEvent::MP::DataConn::_connect:: => $id;
179			}
180			} else {
181			# wait for the next global setup handshake
182			$AnyEvent::MP::Global::ON_SETUP{$id} = $state->{wait};
183			};
184	root	1.1	};
185	root	1.2
186			$state->{wait}->();
187	root	1.1	}
188			}
189
190			=back
191
192			=head1 SEE ALSO
193
194			L<AnyEvent::MP>.
195
196			=head1 AUTHOR
197
198			Marc Lehmann <schmorp@schmorp.de>
199			http://home.schmorp.de/
200
201			=cut
202
203			1
204