AnyEvent-MP/MP/Global.pm

=head1 NAME

AnyEvent::MP::Global - some network-global services

=head1 SYNOPSIS

   use AnyEvent::MP::Global;

=head1 DESCRIPTION

This module maintains a fully-meshed network between global nodes and
tries to have connections with all nodes in the network.

It also manages named port groups - ports can register themselves in any
number of groups that will be available network-wide, which is great for
discovering services.

Running it on one node will automatically run it on all nodes, although,
at the moment, the global service is started by default anyways.

=head1 GLOBALS AND FUNCTIONS

=over 4

=cut

package AnyEvent::MP::Global;

use common::sense;
use Carp ();

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

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

use base "Exporter";

our @EXPORT = qw(
   grp_reg
   grp_get
   grp_mon
);

$AnyEvent::MP::Kernel::WARN->(7, "starting global service.");

#############################################################################
# node protocol parts for global nodes

{
   package AnyEvent::MP::Kernel;

   # TODO: this is ugly, maybe this should go into MP::Kernel or a separate module #d#

   our $GLOBAL;
   our $NODE_ADDR;
   our $GLOBAL_ADDR;
   our $NODE;
   our %GLOBAL_SLAVE;
   our $GLOBAL_MON;
   our $LISTENER;

   # switch to global mode
   $GLOBAL = 1;
   $MASTER = $NODE;
   undef $GLOBAL_MON;

   $GLOBAL_ADDR->{$NODE} = $LISTENER;

   $GLOBAL_MON = mon_nodes sub {
      return if $_[1];

      delete $NODE_ADDR->{$_[0]};

      if (delete $GLOBAL_ADDR->{$_[0]}) {
         # if the node is global, tell our slaves

         our %GLOBAL_SLAVE; # ugh, will be in AnyEvent::MP::Global
         snd $_, g_del => $_[0]
            for keys %GLOBAL_SLAVE;
      }
   };

   # tell everybody who connects that we are a global node
   push @AnyEvent::MP::Transport::HOOK_GREET, sub {
      $_[0]{local_greeting}{global} = 1;
   };

   # tell every global node that connects that we are global too
   push @AnyEvent::MP::Transport::HOOK_CONNECT, sub {
      snd $_[0], g_add => $NODE, $LISTENER
         if $_[0]{remote_greeting}{global};
   };

   # tell everybody else that we are global now
   snd $_ => g_add => $NODE, $LISTENER
      for up_nodes;
}

=item $guard = grp_reg $group, $port

Register the given (local!) port in the named global group C<$group>.

The port will be unregistered automatically when the port is destroyed.

When not called in void context, then a guard object will be returned that
will also cause the name to be unregistered when destroyed.

=cut

# register local port
sub grp_reg($$) {
   my ($group, $port) = @_;

   port_is_local $port
      or Carp::croak "AnyEvent::MP::Global::grp_reg can only be called for local ports, caught";

   defined wantarray && AnyEvent::Util::guard { unregister ($port, $group) }
}

=item $ports = grp_get $group

Returns all the ports currently registered to the given group (as
read-only(!) array reference). When the group has no registered members,
return C<undef>.

=cut

sub grp_get($) {
}

=item $guard = grp_mon $group, $callback->($ports, $add, $del)

Installs a monitor on the given group. Each time there is a change it
will be called with the current group members as an arrayref as the
first argument. The second argument only contains ports added, the third
argument only ports removed.

Unlike C<grp_get>, all three arguments will always be array-refs, even if
the array is empty. None of the arrays must be modified in any way.

The first invocation will be with the first two arguments set to the
current members, as if all of them were just added, but only when the
group is actually non-empty.

Optionally returns a guard object that uninstalls the watcher when it is
destroyed.

=cut

sub grp_mon($$) {
   my ($grp, $cb) = @_;
}

=back

=head1 SEE ALSO

L<AnyEvent::MP>.

=head1 AUTHOR

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

=cut

1

Revision:	1.44
Committed:	Wed Feb 29 18:44:59 2012 UTC (14 years, 7 months ago) by root
Branch:	MAIN
Changes since 1.43:	+39 -259 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3			AnyEvent::MP::Global - some network-global services
4
5			=head1 SYNOPSIS
6
7			use AnyEvent::MP::Global;
8
9			=head1 DESCRIPTION
10
11	root	1.42	This module maintains a fully-meshed network between global nodes and
12			tries to have connections with all nodes in the network.
13	root	1.1
14	root	1.15	It also manages named port groups - ports can register themselves in any
15			number of groups that will be available network-wide, which is great for
16			discovering services.
17	root	1.1
18	root	1.15	Running it on one node will automatically run it on all nodes, although,
19			at the moment, the global service is started by default anyways.
20	root	1.3
21	root	1.1	=head1 GLOBALS AND FUNCTIONS
22
23			=over 4
24
25			=cut
26
27			package AnyEvent::MP::Global;
28
29			use common::sense;
30			use Carp ();
31
32	root	1.8	use AnyEvent ();
33	root	1.4	use AnyEvent::Util ();
34
35	root	1.1	use AnyEvent::MP;
36			use AnyEvent::MP::Kernel;
37	root	1.22	use AnyEvent::MP::Transport ();
38	root	1.1
39	root	1.20	use base "Exporter";
40
41			our @EXPORT = qw(
42			grp_reg
43			grp_get
44			grp_mon
45			);
46
47	root	1.5	$AnyEvent::MP::Kernel::WARN->(7, "starting global service.");
48
49	root	1.8	#############################################################################
50	root	1.44	# node protocol parts for global nodes
51	root	1.8
52	root	1.44	{
53			package AnyEvent::MP::Kernel;
54	root	1.8
55	root	1.44	# TODO: this is ugly, maybe this should go into MP::Kernel or a separate module #d#
56	root	1.26
57	root	1.44	our $GLOBAL;
58			our $NODE_ADDR;
59			our $GLOBAL_ADDR;
60			our $NODE;
61			our %GLOBAL_SLAVE;
62			our $GLOBAL_MON;
63			our $LISTENER;
64	root	1.26
65	root	1.44	# switch to global mode
66			$GLOBAL = 1;
67			$MASTER = $NODE;
68			undef $GLOBAL_MON;
69	root	1.22
70	root	1.44	$GLOBAL_ADDR->{$NODE} = $LISTENER;
71	root	1.8
72	root	1.44	$GLOBAL_MON = mon_nodes sub {
73			return if $_[1];
74	root	1.20
75	root	1.44	delete $NODE_ADDR->{$_[0]};
76	root	1.20
77	root	1.44	if (delete $GLOBAL_ADDR->{$_[0]}) {
78			# if the node is global, tell our slaves
79	root	1.20
80	root	1.44	our %GLOBAL_SLAVE; # ugh, will be in AnyEvent::MP::Global
81			snd $_, g_del => $_[0]
82			for keys %GLOBAL_SLAVE;
83			}
84			};
85	root	1.20
86	root	1.44	# tell everybody who connects that we are a global node
87			push @AnyEvent::MP::Transport::HOOK_GREET, sub {
88			$_[0]{local_greeting}{global} = 1;
89			};
90	root	1.4
91	root	1.44	# tell every global node that connects that we are global too
92			push @AnyEvent::MP::Transport::HOOK_CONNECT, sub {
93			snd $_[0], g_add => $NODE, $LISTENER
94			if $_[0]{remote_greeting}{global};
95			};
96	root	1.4
97	root	1.44	# tell everybody else that we are global now
98			snd $_ => g_add => $NODE, $LISTENER
99			for up_nodes;
100	root	1.4	}
101
102	root	1.20	=item $guard = grp_reg $group, $port
103	root	1.4
104			Register the given (local!) port in the named global group C<$group>.
105
106			The port will be unregistered automatically when the port is destroyed.
107
108			When not called in void context, then a guard object will be returned that
109			will also cause the name to be unregistered when destroyed.
110
111			=cut
112
113			# register local port
114	root	1.20	sub grp_reg($$) {
115			my ($group, $port) = @_;
116	root	1.4
117			port_is_local $port
118	root	1.20	or Carp::croak "AnyEvent::MP::Global::grp_reg can only be called for local ports, caught";
119
120	root	1.44	defined wantarray && AnyEvent::Util::guard { unregister ($port, $group) }
121	root	1.4	}
122
123	root	1.20	=item $ports = grp_get $group
124	root	1.15
125			Returns all the ports currently registered to the given group (as
126	root	1.20	read-only(!) array reference). When the group has no registered members,
127	root	1.15	return C<undef>.
128
129			=cut
130
131	root	1.20	sub grp_get($) {
132			}
133
134			=item $guard = grp_mon $group, $callback->($ports, $add, $del)
135
136			Installs a monitor on the given group. Each time there is a change it
137			will be called with the current group members as an arrayref as the
138			first argument. The second argument only contains ports added, the third
139			argument only ports removed.
140
141			Unlike C<grp_get>, all three arguments will always be array-refs, even if
142			the array is empty. None of the arrays must be modified in any way.
143
144			The first invocation will be with the first two arguments set to the
145			current members, as if all of them were just added, but only when the
146	root	1.39	group is actually non-empty.
147	root	1.20
148			Optionally returns a guard object that uninstalls the watcher when it is
149			destroyed.
150
151			=cut
152
153			sub grp_mon($$) {
154			my ($grp, $cb) = @_;
155	root	1.4	}
156	root	1.3
157	root	1.1	=back
158
159			=head1 SEE ALSO
160
161			L<AnyEvent::MP>.
162
163			=head1 AUTHOR
164
165			Marc Lehmann <schmorp@schmorp.de>
166			http://home.schmorp.de/
167
168			=cut
169
170			1
171