AnyEvent-MP/MP/Kernel.pm

=head1 NAME

AnyEvent::MP::Kernel - the actual message passing kernel

=head1 SYNOPSIS

   use AnyEvent::MP::Kernel;

=head1 DESCRIPTION

This module provides most of the basic functionality of AnyEvent::MP,
exposed through higher level interfaces such as L<AnyEvent::MP> and
L<Coro::MP>.

This module is mainly of interest when knowledge about connectivity,
connected nodes etc. are needed.

=head1 GLOBALS AND FUNCTIONS

=over 4

=cut

package AnyEvent::MP::Kernel;

use common::sense;
use POSIX ();
use Carp ();
use MIME::Base64 ();

use AE ();

use AnyEvent::MP::Node;
use AnyEvent::MP::Transport;

use base "Exporter";

our $VERSION = '0.8';
our @EXPORT = qw(
   %NODE %PORT %PORT_DATA $UNIQ $RUNIQ $ID
   add_node load_func snd_to_func snd_on eval_on

   NODE $NODE node_of snd kil
   port_is_local
   resolve_node initialise_node
   known_nodes up_nodes mon_nodes node_is_known node_is_up
);

our $DEFAULT_PORT = "4040";

our $CONNECT_INTERVAL =  2; # new connect every 2s, at least
our $NETWORK_LATENCY  =  3; # activity timeout
our $MONITOR_TIMEOUT  = 15; # fail monitoring after this time

=item $AnyEvent::MP::Kernel::WARN->($level, $msg)

This value is called with an error or warning message, when e.g. a connection
could not be created, authorisation failed and so on.

C<$level> sould be C<0> for messages ot be logged always, C<1> for
unexpected messages and errors, C<2> for warnings, C<7> for messages about
node connectivity and services, C<8> for debugging messages and C<9> for
tracing messages.

The default simply logs the message to STDERR.

=cut

our $WARN = sub {
   my ($level, $msg) = @_;

   $msg =~ s/\n$//;

   printf STDERR "%s <%d> %s\n",
          (POSIX::strftime "%Y-%m-%d %H:%M:%S", localtime time),
          $level,
          $msg;
};

sub load_func($) {
   my $func = $_[0];

   unless (defined &$func) {
      my $pkg = $func;
      do {
         $pkg =~ s/::[^:]+$//
            or return sub { die "unable to resolve '$func'" };
         eval "require $pkg";
      } until defined &$func;
   }

   \&$func
}

sub nonce($) {
   my $nonce;

   if (open my $fh, "</dev/urandom") {
      sysread $fh, $nonce, $_[0];
   } else {
      # shit...
      our $nonce_init;
      unless ($nonce_init++) {
         srand time ^ $$ ^ unpack "%L*", qx"ps -edalf" . qx"ipconfig /all";
      }

      $nonce = join "", map +(chr rand 256), 1 .. $_[0]
   }

   $nonce
}

sub alnumbits($) {
   my $data = $_[0];

   if (eval "use Math::GMP 2.05; 1") {
      $data = Math::GMP::get_str_gmp (
                  (Math::GMP::new_from_scalar_with_base (+(unpack "H*", $data), 16)),
                  62
              );
   } else {
      $data = MIME::Base64::encode_base64 $data, "";
      $data =~ s/=//;
      $data =~ s/\//s/g;
      $data =~ s/\+/p/g;
   }

   $data
}

sub gen_uniq {
   alnumbits pack "wNa*", $$, time, nonce 2
}

=item $AnyEvent::MP::Kernel::PUBLIC

A boolean indicating whether this is a public node, which can create and
accept direct connections from other nodes.

=cut

our $CONFIG; # this node's configuration

our $RUNIQ  = alnumbits nonce 16;; # remote uniq value
our $UNIQ   = gen_uniq; # per-process/node unique cookie
our $NODE   = "anon/$RUNIQ";
our $ID     = "a";

our %NODE; # node id to transport mapping, or "undef", for local node
our (%PORT, %PORT_DATA); # local ports

our %RMON; # local ports monitored by remote nodes ($RMON{nodeid}{portid} == cb)
our %LMON; # monitored _local_ ports

our %LISTENER;
our $LISTENER; # our listeners, as arrayref

our $SRCNODE; # holds the sending node during _inject

sub NODE() {
   $NODE
}

sub node_of($) {
   my ($node, undef) = split /#/, $_[0], 2;

   $node
}

BEGIN {
   *TRACE = $ENV{PERL_ANYEVENT_MP_TRACE}
      ? sub () { 1 }
      : sub () { 0 };
}

sub _inject {
   warn "RCV $SRCNODE->{id} -> @_\n" if TRACE && @_;#d#
   &{ $PORT{+shift} or return };
}

# this function adds a node-ref, so you can send stuff to it
# it is basically the central routing component.
sub add_node {
   my ($node) = @_;

   $NODE{$node} ||= new AnyEvent::MP::Node::Direct $node
}

sub snd(@) {
   my ($nodeid, $portid) = split /#/, shift, 2;

   warn "SND $nodeid <- $portid @_\n" if TRACE;#d#

   ($NODE{$nodeid} || add_node $nodeid)
      ->{send} (["$portid", @_]);
}

=item $is_local = port_is_local $port

Returns true iff the port is a local port.

=cut

sub port_is_local($) {
   my ($nodeid, undef) = split /#/, $_[0], 2;

   $NODE{$nodeid} == $NODE{""}
}

=item snd_to_func $node, $func, @args

Expects a node ID and a name of a function. Asynchronously tries to call
this function with the given arguments on that node.

This function can be used to implement C<spawn>-like interfaces.

=cut

sub snd_to_func($$;@) {
   my $nodeid = shift;

   ($NODE{$nodeid} || add_node $nodeid)
      ->send (["", @_]);
}

=item snd_on $node, @msg

Executes C<snd> with the given C<@msg> (which must include the destination
port) on the given node.

=cut

sub snd_on($@) {
   my $node = shift;
   snd $node, snd => @_;
}

=item eval_on $node, $string

Evaluates the given string as Perl expression on the given node.

=cut

sub eval_on($@) {
   my $node = shift;
   snd $node, eval => @_;
}

sub kil(@) {
   my ($nodeid, $portid) = split /#/, shift, 2;

   length $portid
      or Carp::croak "$nodeid#$portid: killing a node port is not allowed, caught";

   ($NODE{$nodeid} || add_node $nodeid)
      ->kill ("$portid", @_);
}

sub _nodename {
   require POSIX;
   (POSIX::uname ())[1]
}

sub _resolve($) {
   my ($nodeid) = @_;

   my $cv = AE::cv;
   my @res;

   $cv->begin (sub {
      my %seen;
      my @refs;
      for (sort { $a->[0] <=> $b->[0] } @res) {
         push @refs, $_->[1] unless $seen{$_->[1]}++
      }
      shift->send (@refs);
   });

   $nodeid = $DEFAULT_PORT unless length $nodeid;

   my $idx;
   for my $t (split /,/, $nodeid) {
      my $pri = ++$idx;

      $t = length $t ? _nodename . ":$t" : _nodename
         if $t =~ /^\d*$/;
      
      my ($host, $port) = AnyEvent::Socket::parse_hostport $t, "aemp=$DEFAULT_PORT"
         or Carp::croak "$t: unparsable transport descriptor";

      $cv->begin;
      AnyEvent::Socket::resolve_sockaddr $host, $port, "tcp", 0, undef, sub {
         for (@_) {
            my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3];
            push @res, [
               $pri += 1e-5,
               AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service
            ];
         }
         $cv->end;
      };
   }

   $cv->end;

   $cv
}

sub initialise_node(;$%) {
   my ($profile) = @_;

   $profile = _nodename
      unless defined $profile;

   $CONFIG = AnyEvent::MP::Config::find_profile $profile;
   $NODE = exists $CONFIG->{nodeid} ? $CONFIG->{nodeid}
         : $profile eq "anon/"      ? $NODE
                                    : $profile;

   $NODE{$NODE} = $NODE{""};
   $NODE{$NODE}{id} = $NODE;

   my $seeds = $CONFIG->{seeds};
   my $binds = $CONFIG->{binds};

   $binds ||= [$NODE];

   $WARN->(8, "node $NODE starting up.");

   $LISTENER = [];
   %LISTENER = ();

   for (map _resolve $_, @$binds) {
      for my $bind ($_->recv) {
         my ($host, $port) = AnyEvent::Socket::parse_hostport $bind
            or Carp::croak "$bind: unparsable local bind address";

         $LISTENER{$bind} = AnyEvent::MP::Transport::mp_server $host, $port;
         push @$LISTENER, $bind;
      }
   }

   # the global service is mandatory currently
   require AnyEvent::MP::Global;

   # connect to all seednodes
   AnyEvent::MP::Global::set_seeds (map $_->recv, map _resolve $_, @$seeds);

   for (@{ $CONFIG->{services} }) {
      if (s/::$//) {
         eval "require $_";
         die $@ if $@;
      } else {
         (load_func $_)->();
      }
   }
}

#############################################################################
# node monitoring and info

sub _uniq_nodes {
   my %node;

   @node{values %NODE} = values %NODE;

   values %node;
}

sub _public_nodes {
   &_uniq_nodes
}

=item node_is_known $nodeid

Returns true iff the given node is currently known to the system.

=cut

sub node_is_known($) {
   exists $NODE{$_[0]}
}

=item node_is_up $nodeid

Returns true if the given node is "up", that is, the kernel thinks it has
a working connection to it.

If the node is known but not currently connected, returns C<0>. If the
node is not known, returns C<undef>.

=cut

sub node_is_up($) {
   ($NODE{$_[0]} or return)->{transport}
      ? 1 : 0
}

=item known_nodes

Returns the node IDs of all public nodes connected to this node, including
itself.

=cut

sub known_nodes {
   map $_->{id}, _public_nodes
}

=item up_nodes

Return the node IDs of all public nodes that are currently connected
(excluding the node itself).

=cut

sub up_nodes {
   map $_->{id}, grep $_->{transport}, _public_nodes
}

=item $guard = mon_nodes $callback->($nodeid, $is_up, @reason)

Registers a callback that is called each time a node goes up (connection
is established) or down (connection is lost).

Node up messages can only be followed by node down messages for the same
node, and vice versa.

The function returns an optional guard which can be used to de-register
the monitoring callback again.

=cut

our %MON_NODES;

sub mon_nodes($) {
   my ($cb) = @_;

   $MON_NODES{$cb+0} = $cb;

   wantarray && AnyEvent::Util::guard { delete $MON_NODES{$cb+0} }
}

sub _inject_nodeevent($$;@) {
   my ($node, $up, @reason) = @_;

   for my $cb (values %MON_NODES) {
      eval { $cb->($node->{id}, $up, @reason); 1 }
         or $WARN->(1, $@);
   }

   $WARN->(7, "$node->{id} is " . ($up ? "up" : "down") . " (@reason)");
}

#############################################################################
# self node code

our %node_req = (
   # internal services

   # monitoring
   mon0 => sub { # disable monitoring
      my $portid = shift;
      my $node   = $SRCNODE;
      $NODE{""}->unmonitor ($portid, delete $node->{rmon}{$portid});
   },
   mon1 => sub { # enable monitoring
      my $portid = shift;
      my $node   = $SRCNODE;
      $NODE{""}->monitor ($portid, $node->{rmon}{$portid} = sub {
         $node->send (["", kil => $portid, @_]);
      });
   },
   kil => sub {
      my $cbs = delete $SRCNODE->{lmon}{+shift}
         or return;

      $_->(@_) for @$cbs;
   },

   # "public" services - not actually public

   # relay message to another node / generic echo
   snd => \&snd,
   snd_multi => sub {
      snd @$_ for @_
   },

   # informational
   info => sub {
      snd @_, $NODE;
   },
   known_nodes => sub {
      snd @_, known_nodes;
   },
   up_nodes => sub {
      snd @_, up_nodes;
   },

   # random garbage
   eval => sub {
      my @res = eval shift;
      snd @_, "$@", @res if @_;
   },
   time => sub {
      snd @_, AE::time;
   },
   devnull => sub {
      #
   },
   "" => sub {
      # empty messages are sent by monitoring
   },
);

$NODE{""} = $NODE{$NODE} = new AnyEvent::MP::Node::Self $NODE;
$PORT{""} = sub {
   my $tag = shift;
   eval { &{ $node_req{$tag} ||= load_func $tag } };
   $WARN->(2, "error processing node message: $@") if $@;
};

=back

=head1 SEE ALSO

L<AnyEvent::MP>.

=head1 AUTHOR

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

=cut

1

Revision:	1.23
Committed:	Thu Aug 27 23:46:33 2009 UTC (14 years, 9 months ago) by root
Branch:	MAIN
Changes since 1.22:	+3 -0 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	=head1 NAME
2
3	root	1.3	AnyEvent::MP::Kernel - the actual message passing kernel
4	root	1.1
5			=head1 SYNOPSIS
6
7	root	1.3	use AnyEvent::MP::Kernel;
8	root	1.1
9			=head1 DESCRIPTION
10
11			This module provides most of the basic functionality of AnyEvent::MP,
12			exposed through higher level interfaces such as L<AnyEvent::MP> and
13			L<Coro::MP>.
14
15	root	1.3	This module is mainly of interest when knowledge about connectivity,
16			connected nodes etc. are needed.
17
18			=head1 GLOBALS AND FUNCTIONS
19	root	1.1
20			=over 4
21
22			=cut
23
24			package AnyEvent::MP::Kernel;
25
26			use common::sense;
27	root	1.16	use POSIX ();
28	root	1.1	use Carp ();
29			use MIME::Base64 ();
30
31			use AE ();
32
33			use AnyEvent::MP::Node;
34			use AnyEvent::MP::Transport;
35
36			use base "Exporter";
37
38	root	1.19	our $VERSION = '0.8';
39	root	1.1	our @EXPORT = qw(
40	root	1.13	%NODE %PORT %PORT_DATA $UNIQ $RUNIQ $ID
41	root	1.21	add_node load_func snd_to_func snd_on eval_on
42	root	1.1
43	root	1.10	NODE $NODE node_of snd kil
44	root	1.17	port_is_local
45	root	1.1	resolve_node initialise_node
46	root	1.13	known_nodes up_nodes mon_nodes node_is_known node_is_up
47	root	1.1	);
48
49			our $DEFAULT_PORT = "4040";
50
51			our $CONNECT_INTERVAL = 2; # new connect every 2s, at least
52			our $NETWORK_LATENCY = 3; # activity timeout
53			our $MONITOR_TIMEOUT = 15; # fail monitoring after this time
54
55	root	1.16	=item $AnyEvent::MP::Kernel::WARN->($level, $msg)
56	root	1.1
57			This value is called with an error or warning message, when e.g. a connection
58			could not be created, authorisation failed and so on.
59
60	root	1.16	C<$level> sould be C<0> for messages ot be logged always, C<1> for
61			unexpected messages and errors, C<2> for warnings, C<7> for messages about
62			node connectivity and services, C<8> for debugging messages and C<9> for
63			tracing messages.
64
65	root	1.1	The default simply logs the message to STDERR.
66
67			=cut
68
69			our $WARN = sub {
70	root	1.16	my ($level, $msg) = @_;
71
72	root	1.1	$msg =~ s/\n$//;
73	root	1.16
74			printf STDERR "%s <%d> %s\n",
75			(POSIX::strftime "%Y-%m-%d %H:%M:%S", localtime time),
76			$level,
77			$msg;
78	root	1.1	};
79
80	root	1.6	sub load_func($) {
81			my $func = $_[0];
82
83			unless (defined &$func) {
84			my $pkg = $func;
85			do {
86			$pkg =~ s/::[^:]+$//
87			or return sub { die "unable to resolve '$func'" };
88			eval "require $pkg";
89			} until defined &$func;
90			}
91
92			\&$func
93			}
94
95	root	1.1	sub nonce($) {
96			my $nonce;
97
98			if (open my $fh, "</dev/urandom") {
99			sysread $fh, $nonce, $_[0];
100			} else {
101			# shit...
102			our $nonce_init;
103			unless ($nonce_init++) {
104			srand time ^ $$ ^ unpack "%L*", qx"ps -edalf" . qx"ipconfig /all";
105			}
106
107			$nonce = join "", map +(chr rand 256), 1 .. $_[0]
108			}
109
110			$nonce
111			}
112
113	root	1.21	sub alnumbits($) {
114	root	1.1	my $data = $_[0];
115
116			if (eval "use Math::GMP 2.05; 1") {
117			$data = Math::GMP::get_str_gmp (
118			(Math::GMP::new_from_scalar_with_base (+(unpack "H*", $data), 16)),
119			62
120			);
121			} else {
122			$data = MIME::Base64::encode_base64 $data, "";
123			$data =~ s/=//;
124			$data =~ s/\//s/g;
125			$data =~ s/\+/p/g;
126			}
127
128			$data
129			}
130
131			sub gen_uniq {
132	root	1.21	alnumbits pack "wNa*", $$, time, nonce 2
133	root	1.1	}
134
135	root	1.3	=item $AnyEvent::MP::Kernel::PUBLIC
136
137	root	1.21	A boolean indicating whether this is a public node, which can create and
138			accept direct connections from other nodes.
139	root	1.3
140			=cut
141
142	root	1.20	our $CONFIG; # this node's configuration
143	root	1.21
144			our $RUNIQ = alnumbits nonce 16;; # remote uniq value
145	root	1.1	our $UNIQ = gen_uniq; # per-process/node unique cookie
146	root	1.21	our $NODE = "anon/$RUNIQ";
147	root	1.1	our $ID = "a";
148
149			our %NODE; # node id to transport mapping, or "undef", for local node
150			our (%PORT, %PORT_DATA); # local ports
151
152	root	1.21	our %RMON; # local ports monitored by remote nodes ($RMON{nodeid}{portid} == cb)
153	root	1.1	our %LMON; # monitored _local_ ports
154
155			our %LISTENER;
156	root	1.21	our $LISTENER; # our listeners, as arrayref
157	root	1.1
158			our $SRCNODE; # holds the sending node during _inject
159
160			sub NODE() {
161			$NODE
162			}
163
164			sub node_of($) {
165	root	1.21	my ($node, undef) = split /#/, $_[0], 2;
166	root	1.1
167	root	1.21	$node
168	root	1.1	}
169
170	root	1.17	BEGIN {
171			*TRACE = $ENV{PERL_ANYEVENT_MP_TRACE}
172			? sub () { 1 }
173			: sub () { 0 };
174			}
175	root	1.1
176			sub _inject {
177	root	1.21	warn "RCV $SRCNODE->{id} -> @_\n" if TRACE && @_;#d#
178	root	1.1	&{ $PORT{+shift} or return };
179			}
180
181	root	1.20	# this function adds a node-ref, so you can send stuff to it
182			# it is basically the central routing component.
183	root	1.1	sub add_node {
184	root	1.21	my ($node) = @_;
185	root	1.1
186	root	1.21	$NODE{$node} \|\|= new AnyEvent::MP::Node::Direct $node
187	root	1.13	}
188
189	root	1.1	sub snd(@) {
190	root	1.21	my ($nodeid, $portid) = split /#/, shift, 2;
191	root	1.1
192	root	1.21	warn "SND $nodeid <- $portid @_\n" if TRACE;#d#
193	root	1.1
194	root	1.21	($NODE{$nodeid} \|\| add_node $nodeid)
195	root	1.2	->{send} (["$portid", @_]);
196	root	1.1	}
197
198	root	1.17	=item $is_local = port_is_local $port
199
200			Returns true iff the port is a local port.
201
202			=cut
203
204			sub port_is_local($) {
205	root	1.21	my ($nodeid, undef) = split /#/, $_[0], 2;
206	root	1.17
207	root	1.21	$NODE{$nodeid} == $NODE{""}
208	root	1.17	}
209
210	root	1.18	=item snd_to_func $node, $func, @args
211	root	1.11
212	root	1.21	Expects a node ID and a name of a function. Asynchronously tries to call
213	root	1.11	this function with the given arguments on that node.
214
215	root	1.20	This function can be used to implement C<spawn>-like interfaces.
216	root	1.11
217			=cut
218
219	root	1.18	sub snd_to_func($$;@) {
220	root	1.21	my $nodeid = shift;
221	root	1.11
222	root	1.21	($NODE{$nodeid} \|\| add_node $nodeid)
223	root	1.11	->send (["", @_]);
224			}
225
226	root	1.18	=item snd_on $node, @msg
227
228			Executes C<snd> with the given C<@msg> (which must include the destination
229			port) on the given node.
230
231			=cut
232
233			sub snd_on($@) {
234			my $node = shift;
235			snd $node, snd => @_;
236			}
237
238			=item eval_on $node, $string
239
240			Evaluates the given string as Perl expression on the given node.
241
242			=cut
243
244			sub eval_on($@) {
245			my $node = shift;
246			snd $node, eval => @_;
247			}
248
249	root	1.1	sub kil(@) {
250	root	1.21	my ($nodeid, $portid) = split /#/, shift, 2;
251	root	1.1
252			length $portid
253	root	1.21	or Carp::croak "$nodeid#$portid: killing a node port is not allowed, caught";
254	root	1.1
255	root	1.21	($NODE{$nodeid} \|\| add_node $nodeid)
256	root	1.1	->kill ("$portid", @_);
257			}
258
259	root	1.7	sub _nodename {
260			require POSIX;
261			(POSIX::uname ())[1]
262			}
263
264	root	1.21	sub _resolve($) {
265			my ($nodeid) = @_;
266	root	1.1
267			my $cv = AE::cv;
268			my @res;
269
270			$cv->begin (sub {
271			my %seen;
272			my @refs;
273			for (sort { $a->[0] <=> $b->[0] } @res) {
274			push @refs, $_->[1] unless $seen{$_->[1]}++
275			}
276	root	1.21	shift->send (@refs);
277	root	1.1	});
278
279	root	1.21	$nodeid = $DEFAULT_PORT unless length $nodeid;
280	root	1.1
281			my $idx;
282	root	1.21	for my $t (split /,/, $nodeid) {
283	root	1.1	my $pri = ++$idx;
284	root	1.7
285			$t = length $t ? _nodename . ":$t" : _nodename
286			if $t =~ /^\d*$/;
287	root	1.1
288	root	1.7	my ($host, $port) = AnyEvent::Socket::parse_hostport $t, "aemp=$DEFAULT_PORT"
289			or Carp::croak "$t: unparsable transport descriptor";
290
291			$cv->begin;
292			AnyEvent::Socket::resolve_sockaddr $host, $port, "tcp", 0, undef, sub {
293			for (@_) {
294			my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3];
295			push @res, [
296			$pri += 1e-5,
297			AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service
298			];
299	root	1.1	}
300	root	1.7	$cv->end;
301			};
302	root	1.1	}
303
304			$cv->end;
305
306			$cv
307			}
308
309	root	1.22	sub initialise_node(;$%) {
310	root	1.21	my ($profile) = @_;
311	root	1.1
312	root	1.21	$profile = _nodename
313			unless defined $profile;
314	root	1.6
315	root	1.21	$CONFIG = AnyEvent::MP::Config::find_profile $profile;
316			$NODE = exists $CONFIG->{nodeid} ? $CONFIG->{nodeid}
317			: $profile eq "anon/" ? $NODE
318			: $profile;
319	root	1.6
320	root	1.21	$NODE{$NODE} = $NODE{""};
321			$NODE{$NODE}{id} = $NODE;
322	root	1.20
323	root	1.21	my $seeds = $CONFIG->{seeds};
324			my $binds = $CONFIG->{binds};
325	root	1.3
326	root	1.21	$binds \|\|= [$NODE];
327	root	1.1
328	root	1.21	$WARN->(8, "node $NODE starting up.");
329	root	1.1
330	root	1.23	$LISTENER = [];
331			%LISTENER = ();
332
333	root	1.21	for (map _resolve $_, @$binds) {
334			for my $bind ($_->recv) {
335			my ($host, $port) = AnyEvent::Socket::parse_hostport $bind
336			or Carp::croak "$bind: unparsable local bind address";
337	root	1.20
338	root	1.21	$LISTENER{$bind} = AnyEvent::MP::Transport::mp_server $host, $port;
339			push @$LISTENER, $bind;
340			}
341	root	1.1	}
342
343	root	1.21	# the global service is mandatory currently
344			require AnyEvent::MP::Global;
345	root	1.1
346	root	1.21	# connect to all seednodes
347			AnyEvent::MP::Global::set_seeds (map $_->recv, map _resolve $_, @$seeds);
348	root	1.1
349	root	1.20	for (@{ $CONFIG->{services} }) {
350	root	1.13	if (s/::$//) {
351			eval "require $_";
352			die $@ if $@;
353			} else {
354			(load_func $_)->();
355			}
356			}
357	root	1.1	}
358
359			#############################################################################
360	root	1.6	# node monitoring and info
361	root	1.3
362			sub _uniq_nodes {
363			my %node;
364
365			@node{values %NODE} = values %NODE;
366
367			values %node;
368			}
369
370	root	1.20	sub _public_nodes {
371	root	1.21	&_uniq_nodes
372	root	1.20	}
373
374	root	1.21	=item node_is_known $nodeid
375	root	1.13
376			Returns true iff the given node is currently known to the system.
377
378			=cut
379
380			sub node_is_known($) {
381			exists $NODE{$_[0]}
382			}
383
384	root	1.21	=item node_is_up $nodeid
385	root	1.13
386			Returns true if the given node is "up", that is, the kernel thinks it has
387			a working connection to it.
388
389			If the node is known but not currently connected, returns C<0>. If the
390			node is not known, returns C<undef>.
391
392			=cut
393
394			sub node_is_up($) {
395			($NODE{$_[0]} or return)->{transport}
396			? 1 : 0
397			}
398
399	root	1.3	=item known_nodes
400
401	root	1.21	Returns the node IDs of all public nodes connected to this node, including
402	root	1.18	itself.
403	root	1.3
404			=cut
405
406			sub known_nodes {
407	root	1.21	map $_->{id}, _public_nodes
408	root	1.3	}
409
410			=item up_nodes
411
412	root	1.21	Return the node IDs of all public nodes that are currently connected
413	root	1.20	(excluding the node itself).
414	root	1.3
415			=cut
416
417			sub up_nodes {
418	root	1.21	map $_->{id}, grep $_->{transport}, _public_nodes
419	root	1.3	}
420
421	root	1.21	=item $guard = mon_nodes $callback->($nodeid, $is_up, @reason)
422	root	1.3
423			Registers a callback that is called each time a node goes up (connection
424			is established) or down (connection is lost).
425
426			Node up messages can only be followed by node down messages for the same
427			node, and vice versa.
428
429	root	1.13	The function returns an optional guard which can be used to de-register
430	root	1.3	the monitoring callback again.
431
432			=cut
433
434			our %MON_NODES;
435
436			sub mon_nodes($) {
437			my ($cb) = @_;
438
439			$MON_NODES{$cb+0} = $cb;
440
441			wantarray && AnyEvent::Util::guard { delete $MON_NODES{$cb+0} }
442			}
443
444			sub _inject_nodeevent($$;@) {
445	root	1.16	my ($node, $up, @reason) = @_;
446	root	1.3
447			for my $cb (values %MON_NODES) {
448	root	1.21	eval { $cb->($node->{id}, $up, @reason); 1 }
449	root	1.16	or $WARN->(1, $@);
450	root	1.3	}
451	root	1.16
452	root	1.21	$WARN->(7, "$node->{id} is " . ($up ? "up" : "down") . " (@reason)");
453	root	1.3	}
454
455			#############################################################################
456	root	1.1	# self node code
457
458			our %node_req = (
459			# internal services
460
461			# monitoring
462			mon0 => sub { # disable monitoring
463			my $portid = shift;
464			my $node = $SRCNODE;
465			$NODE{""}->unmonitor ($portid, delete $node->{rmon}{$portid});
466			},
467			mon1 => sub { # enable monitoring
468			my $portid = shift;
469			my $node = $SRCNODE;
470			$NODE{""}->monitor ($portid, $node->{rmon}{$portid} = sub {
471			$node->send (["", kil => $portid, @_]);
472			});
473			},
474			kil => sub {
475			my $cbs = delete $SRCNODE->{lmon}{+shift}
476			or return;
477
478			$_->(@_) for @$cbs;
479			},
480
481	root	1.18	# "public" services - not actually public
482	root	1.1
483			# relay message to another node / generic echo
484	root	1.15	snd => \&snd,
485			snd_multi => sub {
486	root	1.1	snd @$_ for @_
487			},
488
489	root	1.4	# informational
490			info => sub {
491			snd @_, $NODE;
492			},
493			known_nodes => sub {
494			snd @_, known_nodes;
495			},
496			up_nodes => sub {
497			snd @_, up_nodes;
498			},
499
500	root	1.1	# random garbage
501			eval => sub {
502			my @res = eval shift;
503			snd @_, "$@", @res if @_;
504			},
505			time => sub {
506			snd @_, AE::time;
507			},
508			devnull => sub {
509			#
510			},
511	root	1.15	"" => sub {
512			# empty messages are sent by monitoring
513			},
514	root	1.1	);
515
516	root	1.18	$NODE{""} = $NODE{$NODE} = new AnyEvent::MP::Node::Self $NODE;
517	root	1.1	$PORT{""} = sub {
518			my $tag = shift;
519			eval { &{ $node_req{$tag} \|\|= load_func $tag } };
520	root	1.16	$WARN->(2, "error processing node message: $@") if $@;
521	root	1.1	};
522
523			=back
524
525			=head1 SEE ALSO
526
527			L<AnyEvent::MP>.
528
529			=head1 AUTHOR
530
531			Marc Lehmann <schmorp@schmorp.de>
532			http://home.schmorp.de/
533
534			=cut
535
536			1
537