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. is sought.

=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 = '0.95';
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
   configure
   known_nodes up_nodes mon_nodes node_is_known node_is_up
);

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.

It I<must not> block or send messages -queue it and use an idle watcher if
you need to do any of these things.

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 $WARNLEVEL = exists $ENV{PERL_ANYEVENT_MP_WARNLEVEL} ? $ENV{PERL_ANYEVENT_MP_WARNLEVEL} : 5;

our $WARN = sub {
   return if $WARNLEVEL < $_[0];

   my ($level, $msg) = @_;

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

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

=item $AnyEvent::MP::Kernel::WARNLEVEL [default 5 or $ENV{PERL_ANYEVENT_MP_WARNLEVEL}]

The maximum level at which warning messages will be printed to STDERR by
the default warn handler.

=cut

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/x/x0/g;
      $data =~ s/\//x1/g;
      $data =~ s/\+/x2/g;
   }

   $data
}

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

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} -> " . (JSON::XS->new->encode (\@_)) . "\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 <- " . (JSON::XS->new->encode (\@_)) . "\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[, @reply]

Evaluates the given string as Perl expression on the given node. When
@reply is specified, then it is used to construct a reply message with
C<"$@"> and any results from the eval appended.

=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);
   });

   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 $t, 0
         or Carp::croak "$t: unparsable transport descriptor";

      $port = "0" if $port eq "*";

      if ($host eq "*") {
         $cv->begin;
         # use fork_call, as Net::Interface is big, and we need it rarely.
         require AnyEvent::Util;
         AnyEvent::Util::fork_call (
            sub {
               my @addr;

               require Net::Interface;

               for my $if (Net::Interface->interfaces) {
                  # we statically lower-prioritise ipv6 here, TODO :()
                  for my $_ ($if->address (Net::Interface::AF_INET ())) {
                     next if /^\x7f/; # skip localhost etc.
                     push @addr, $_;
                  }
                  for ($if->address (Net::Interface::AF_INET6 ())) {
                     #next if $if->scope ($_) <= 2;
                     next unless /^[\x20-\x3f\xfc\xfd]/; # global unicast, site-local unicast
                     push @addr, $_;
                  }

               }
               @addr
            }, sub {
               for my $ip (@_) {
                  push @res, [
                     $pri += 1e-5,
                     AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $ip, $port
                  ];
               }
               $cv->end;
            }
         );
      } else {
         $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 configure(%) {
   my (%kv) = @_;

   my $profile = delete $kv{profile};

   $profile = _nodename
      unless defined $profile;

   $CONFIG = AnyEvent::MP::Config::find_profile $profile, %kv;

   my $node = exists $CONFIG->{nodeid} ? $CONFIG->{nodeid} : $profile;
   $NODE = $node
      unless $node eq "anon/";

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

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

   $binds ||= ["*"];

   $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";

         my $listener = AnyEvent::MP::Transport::mp_server
            $host,
            $port,
            prepare => sub {
               my (undef, $host, $port) = @_;
               $bind = AnyEvent::Socket::format_hostport $host, $port;
            },
         ;
         $LISTENER{$bind} = $listener;
         push @$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

=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 nodes currently known to this node, including
itself and nodes not currently connected.

=cut

sub known_nodes {
   map $_->{id}, values %NODE
}

=item up_nodes

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

=cut

sub up_nodes {
   map $_->{id}, grep $_->{transport}, values %NODE
}

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

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

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

Note that monitoring a node is usually better done by monitoring it's node
port. This function is mainly of interest to modules that are concerned
about the network topology and low-level connection handling.

Callbacks I<must not> block and I<should not> send any messages.

The function returns an optional guard which can be used to unregister
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 { # stop monitoring a port
      my $portid = shift;
      my $node   = $SRCNODE;
      $NODE{""}->unmonitor ($portid, delete $node->{rmon}{$portid});
   },
   mon1 => sub { # start monitoring a port
      my $portid = shift;
      my $node   = $SRCNODE;
      Scalar::Util::weaken $node; #TODO# ugly
      $NODE{""}->monitor ($portid, $node->{rmon}{$portid} = sub {
         $node->send (["", kil => $portid, @_])
            if $node && $node->{transport}; #TODO# ugly, should use snd and remove-on-disocnnect
      });
   },
   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_multiple => sub {
      snd @$_ for @_
   },

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

   # random utilities
   eval => sub {
      my @res = eval shift;
      snd @_, "$@", @res if @_;
   },
   time => sub {
      snd @_, AE::time;
   },
   devnull => sub {
      #
   },
   "" => sub {
      # empty messages are keepalives or similar devnull-applications
   },
);

$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:	1.35
Committed:	Mon Aug 31 20:06:45 2009 UTC (14 years, 9 months ago) by root
Branch:	MAIN
CVS Tags:	rel-0_95
Changes since 1.34:	+1 -1 lines
Log Message:	0.95
#	Content
1	=head1 NAME
2
3	AnyEvent::MP::Kernel - the actual message passing kernel
4
5	=head1 SYNOPSIS
6
7	use AnyEvent::MP::Kernel;
8
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	This module is mainly of interest when knowledge about connectivity,
16	connected nodes etc. is sought.
17
18	=head1 GLOBALS AND FUNCTIONS
19
20	=over 4
21
22	=cut
23
24	package AnyEvent::MP::Kernel;
25
26	use common::sense;
27	use POSIX ();
28	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	our $VERSION = '0.95';
39	our @EXPORT = qw(
40	%NODE %PORT %PORT_DATA $UNIQ $RUNIQ $ID
41	add_node load_func snd_to_func snd_on eval_on
42
43	NODE $NODE node_of snd kil port_is_local
44	configure
45	known_nodes up_nodes mon_nodes node_is_known node_is_up
46	);
47
48	our $CONNECT_INTERVAL = 2; # new connect every 2s, at least
49	our $NETWORK_LATENCY = 3; # activity timeout
50	our $MONITOR_TIMEOUT = 15; # fail monitoring after this time
51
52	=item $AnyEvent::MP::Kernel::WARN->($level, $msg)
53
54	This value is called with an error or warning message, when e.g. a
55	connection could not be created, authorisation failed and so on.
56
57	It I<must not> block or send messages -queue it and use an idle watcher if
58	you need to do any of these things.
59
60	C<$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	The default simply logs the message to STDERR.
66
67	=cut
68
69	our $WARNLEVEL = exists $ENV{PERL_ANYEVENT_MP_WARNLEVEL} ? $ENV{PERL_ANYEVENT_MP_WARNLEVEL} : 5;
70
71	our $WARN = sub {
72	return if $WARNLEVEL < $_[0];
73
74	my ($level, $msg) = @_;
75
76	$msg =~ s/\n$//;
77
78	printf STDERR "%s <%d> %s\n",
79	(POSIX::strftime "%Y-%m-%d %H:%M:%S", localtime time),
80	$level,
81	$msg;
82	};
83
84	=item $AnyEvent::MP::Kernel::WARNLEVEL [default 5 or $ENV{PERL_ANYEVENT_MP_WARNLEVEL}]
85
86	The maximum level at which warning messages will be printed to STDERR by
87	the default warn handler.
88
89	=cut
90
91	sub load_func($) {
92	my $func = $_[0];
93
94	unless (defined &$func) {
95	my $pkg = $func;
96	do {
97	$pkg =~ s/::[^:]+$//
98	or return sub { die "unable to resolve '$func'" };
99	eval "require $pkg";
100	} until defined &$func;
101	}
102
103	\&$func
104	}
105
106	sub nonce($) {
107	my $nonce;
108
109	if (open my $fh, "</dev/urandom") {
110	sysread $fh, $nonce, $_[0];
111	} else {
112	# shit...
113	our $nonce_init;
114	unless ($nonce_init++) {
115	srand time ^ $$ ^ unpack "%L*", qx"ps -edalf" . qx"ipconfig /all";
116	}
117	$nonce = join "", map +(chr rand 256), 1 .. $_[0]
118	}
119
120	$nonce
121	}
122
123	sub alnumbits($) {
124	my $data = $_[0];
125
126	if (eval "use Math::GMP 2.05; 1") {
127	$data = Math::GMP::get_str_gmp (
128	(Math::GMP::new_from_scalar_with_base (+(unpack "H*", $data), 16)),
129	62
130	);
131	} else {
132	$data = MIME::Base64::encode_base64 $data, "";
133	$data =~ s/=//;
134	$data =~ s/x/x0/g;
135	$data =~ s/\//x1/g;
136	$data =~ s/\+/x2/g;
137	}
138
139	$data
140	}
141
142	sub gen_uniq {
143	alnumbits pack "wNa*", $$, time, nonce 2
144	}
145
146	our $CONFIG; # this node's configuration
147
148	our $RUNIQ = alnumbits nonce 16;; # remote uniq value
149	our $UNIQ = gen_uniq; # per-process/node unique cookie
150	our $NODE = "anon/$RUNIQ";
151	our $ID = "a";
152
153	our %NODE; # node id to transport mapping, or "undef", for local node
154	our (%PORT, %PORT_DATA); # local ports
155
156	our %RMON; # local ports monitored by remote nodes ($RMON{nodeid}{portid} == cb)
157	our %LMON; # monitored _local_ ports
158
159	our %LISTENER;
160	our $LISTENER; # our listeners, as arrayref
161
162	our $SRCNODE; # holds the sending node during _inject
163
164	sub NODE() {
165	$NODE
166	}
167
168	sub node_of($) {
169	my ($node, undef) = split /#/, $_[0], 2;
170
171	$node
172	}
173
174	BEGIN {
175	*TRACE = $ENV{PERL_ANYEVENT_MP_TRACE}
176	? sub () { 1 }
177	: sub () { 0 };
178	}
179
180	sub _inject {
181	warn "RCV $SRCNODE->{id} -> " . (JSON::XS->new->encode (\@_)) . "\n" if TRACE && @_;#d#
182	&{ $PORT{+shift} or return };
183	}
184
185	# this function adds a node-ref, so you can send stuff to it
186	# it is basically the central routing component.
187	sub add_node {
188	my ($node) = @_;
189
190	$NODE{$node} \|\|= new AnyEvent::MP::Node::Direct $node
191	}
192
193	sub snd(@) {
194	my ($nodeid, $portid) = split /#/, shift, 2;
195
196	warn "SND $nodeid <- " . (JSON::XS->new->encode (\@_)) . "\n" if TRACE && @_;#d#
197
198	($NODE{$nodeid} \|\| add_node $nodeid)
199	->{send} (["$portid", @_]);
200	}
201
202	=item $is_local = port_is_local $port
203
204	Returns true iff the port is a local port.
205
206	=cut
207
208	sub port_is_local($) {
209	my ($nodeid, undef) = split /#/, $_[0], 2;
210
211	$NODE{$nodeid} == $NODE{""}
212	}
213
214	=item snd_to_func $node, $func, @args
215
216	Expects a node ID and a name of a function. Asynchronously tries to call
217	this function with the given arguments on that node.
218
219	This function can be used to implement C<spawn>-like interfaces.
220
221	=cut
222
223	sub snd_to_func($$;@) {
224	my $nodeid = shift;
225
226	($NODE{$nodeid} \|\| add_node $nodeid)
227	->send (["", @_]);
228	}
229
230	=item snd_on $node, @msg
231
232	Executes C<snd> with the given C<@msg> (which must include the destination
233	port) on the given node.
234
235	=cut
236
237	sub snd_on($@) {
238	my $node = shift;
239	snd $node, snd => @_;
240	}
241
242	=item eval_on $node, $string[, @reply]
243
244	Evaluates the given string as Perl expression on the given node. When
245	@reply is specified, then it is used to construct a reply message with
246	C<"$@"> and any results from the eval appended.
247
248	=cut
249
250	sub eval_on($$;@) {
251	my $node = shift;
252	snd $node, eval => @_;
253	}
254
255	sub kil(@) {
256	my ($nodeid, $portid) = split /#/, shift, 2;
257
258	length $portid
259	or Carp::croak "$nodeid#$portid: killing a node port is not allowed, caught";
260
261	($NODE{$nodeid} \|\| add_node $nodeid)
262	->kill ("$portid", @_);
263	}
264
265	sub _nodename {
266	require POSIX;
267	(POSIX::uname ())[1]
268	}
269
270	sub _resolve($) {
271	my ($nodeid) = @_;
272
273	my $cv = AE::cv;
274	my @res;
275
276	$cv->begin (sub {
277	my %seen;
278	my @refs;
279	for (sort { $a->[0] <=> $b->[0] } @res) {
280	push @refs, $_->[1] unless $seen{$_->[1]}++
281	}
282	shift->send (@refs);
283	});
284
285	my $idx;
286	for my $t (split /,/, $nodeid) {
287	my $pri = ++$idx;
288
289	$t = length $t ? _nodename . ":$t" : _nodename
290	if $t =~ /^\d*$/;
291
292	my ($host, $port) = AnyEvent::Socket::parse_hostport $t, 0
293	or Carp::croak "$t: unparsable transport descriptor";
294
295	$port = "0" if $port eq "*";
296
297	if ($host eq "*") {
298	$cv->begin;
299	# use fork_call, as Net::Interface is big, and we need it rarely.
300	require AnyEvent::Util;
301	AnyEvent::Util::fork_call (
302	sub {
303	my @addr;
304
305	require Net::Interface;
306
307	for my $if (Net::Interface->interfaces) {
308	# we statically lower-prioritise ipv6 here, TODO :()
309	for my $_ ($if->address (Net::Interface::AF_INET ())) {
310	next if /^\x7f/; # skip localhost etc.
311	push @addr, $_;
312	}
313	for ($if->address (Net::Interface::AF_INET6 ())) {
314	#next if $if->scope ($_) <= 2;
315	next unless /^[\x20-\x3f\xfc\xfd]/; # global unicast, site-local unicast
316	push @addr, $_;
317	}
318
319	}
320	@addr
321	}, sub {
322	for my $ip (@_) {
323	push @res, [
324	$pri += 1e-5,
325	AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $ip, $port
326	];
327	}
328	$cv->end;
329	}
330	);
331	} else {
332	$cv->begin;
333	AnyEvent::Socket::resolve_sockaddr $host, $port, "tcp", 0, undef, sub {
334	for (@_) {
335	my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3];
336	push @res, [
337	$pri += 1e-5,
338	AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service
339	];
340	}
341	$cv->end;
342	};
343	}
344	}
345
346	$cv->end;
347
348	$cv
349	}
350
351	sub configure(%) {
352	my (%kv) = @_;
353
354	my $profile = delete $kv{profile};
355
356	$profile = _nodename
357	unless defined $profile;
358
359	$CONFIG = AnyEvent::MP::Config::find_profile $profile, %kv;
360
361	my $node = exists $CONFIG->{nodeid} ? $CONFIG->{nodeid} : $profile;
362	$NODE = $node
363	unless $node eq "anon/";
364
365	$NODE{$NODE} = $NODE{""};
366	$NODE{$NODE}{id} = $NODE;
367
368	my $seeds = $CONFIG->{seeds};
369	my $binds = $CONFIG->{binds};
370
371	$binds \|\|= ["*"];
372
373	$WARN->(8, "node $NODE starting up.");
374
375	$LISTENER = [];
376	%LISTENER = ();
377
378	for (map _resolve $_, @$binds) {
379	for my $bind ($_->recv) {
380	my ($host, $port) = AnyEvent::Socket::parse_hostport $bind
381	or Carp::croak "$bind: unparsable local bind address";
382
383	my $listener = AnyEvent::MP::Transport::mp_server
384	$host,
385	$port,
386	prepare => sub {
387	my (undef, $host, $port) = @_;
388	$bind = AnyEvent::Socket::format_hostport $host, $port;
389	},
390	;
391	$LISTENER{$bind} = $listener;
392	push @$LISTENER, $bind;
393	}
394	}
395
396	# the global service is mandatory currently
397	require AnyEvent::MP::Global;
398
399	# connect to all seednodes
400	AnyEvent::MP::Global::set_seeds (map $_->recv, map _resolve $_, @$seeds);
401
402	for (@{ $CONFIG->{services} }) {
403	if (s/::$//) {
404	eval "require $_";
405	die $@ if $@;
406	} else {
407	(load_func $_)->();
408	}
409	}
410	}
411
412	#############################################################################
413	# node monitoring and info
414
415	=item node_is_known $nodeid
416
417	Returns true iff the given node is currently known to the system.
418
419	=cut
420
421	sub node_is_known($) {
422	exists $NODE{$_[0]}
423	}
424
425	=item node_is_up $nodeid
426
427	Returns true if the given node is "up", that is, the kernel thinks it has
428	a working connection to it.
429
430	If the node is known but not currently connected, returns C<0>. If the
431	node is not known, returns C<undef>.
432
433	=cut
434
435	sub node_is_up($) {
436	($NODE{$_[0]} or return)->{transport}
437	? 1 : 0
438	}
439
440	=item known_nodes
441
442	Returns the node IDs of all nodes currently known to this node, including
443	itself and nodes not currently connected.
444
445	=cut
446
447	sub known_nodes {
448	map $_->{id}, values %NODE
449	}
450
451	=item up_nodes
452
453	Return the node IDs of all nodes that are currently connected (excluding
454	the node itself).
455
456	=cut
457
458	sub up_nodes {
459	map $_->{id}, grep $_->{transport}, values %NODE
460	}
461
462	=item $guard = mon_nodes $callback->($nodeid, $is_up, @reason)
463
464	Registers a callback that is called each time a node goes up (a connection
465	is established) or down (the connection is lost).
466
467	Node up messages can only be followed by node down messages for the same
468	node, and vice versa.
469
470	Note that monitoring a node is usually better done by monitoring it's node
471	port. This function is mainly of interest to modules that are concerned
472	about the network topology and low-level connection handling.
473
474	Callbacks I<must not> block and I<should not> send any messages.
475
476	The function returns an optional guard which can be used to unregister
477	the monitoring callback again.
478
479	=cut
480
481	our %MON_NODES;
482
483	sub mon_nodes($) {
484	my ($cb) = @_;
485
486	$MON_NODES{$cb+0} = $cb;
487
488	wantarray && AnyEvent::Util::guard { delete $MON_NODES{$cb+0} }
489	}
490
491	sub _inject_nodeevent($$;@) {
492	my ($node, $up, @reason) = @_;
493
494	for my $cb (values %MON_NODES) {
495	eval { $cb->($node->{id}, $up, @reason); 1 }
496	or $WARN->(1, $@);
497	}
498
499	$WARN->(7, "$node->{id} is " . ($up ? "up" : "down") . " (@reason)");
500	}
501
502	#############################################################################
503	# self node code
504
505	our %node_req = (
506	# internal services
507
508	# monitoring
509	mon0 => sub { # stop monitoring a port
510	my $portid = shift;
511	my $node = $SRCNODE;
512	$NODE{""}->unmonitor ($portid, delete $node->{rmon}{$portid});
513	},
514	mon1 => sub { # start monitoring a port
515	my $portid = shift;
516	my $node = $SRCNODE;
517	Scalar::Util::weaken $node; #TODO# ugly
518	$NODE{""}->monitor ($portid, $node->{rmon}{$portid} = sub {
519	$node->send (["", kil => $portid, @_])
520	if $node && $node->{transport}; #TODO# ugly, should use snd and remove-on-disocnnect
521	});
522	},
523	kil => sub {
524	my $cbs = delete $SRCNODE->{lmon}{+shift}
525	or return;
526
527	$_->(@_) for @$cbs;
528	},
529
530	# "public" services - not actually public
531
532	# relay message to another node / generic echo
533	snd => \&snd,
534	snd_multiple => sub {
535	snd @$_ for @_
536	},
537
538	# informational
539	info => sub {
540	snd @_, $NODE;
541	},
542	known_nodes => sub {
543	snd @_, known_nodes;
544	},
545	up_nodes => sub {
546	snd @_, up_nodes;
547	},
548
549	# random utilities
550	eval => sub {
551	my @res = eval shift;
552	snd @_, "$@", @res if @_;
553	},
554	time => sub {
555	snd @_, AE::time;
556	},
557	devnull => sub {
558	#
559	},
560	"" => sub {
561	# empty messages are keepalives or similar devnull-applications
562	},
563	);
564
565	$NODE{""} = $NODE{$NODE} = new AnyEvent::MP::Node::Self $NODE;
566	$PORT{""} = sub {
567	my $tag = shift;
568	eval { &{ $node_req{$tag} \|\|= load_func $tag } };
569	$WARN->(2, "error processing node message: $@") if $@;
570	};
571
572	=back
573
574	=head1 SEE ALSO
575
576	L<AnyEvent::MP>.
577
578	=head1 AUTHOR
579
580	Marc Lehmann <schmorp@schmorp.de>
581	http://home.schmorp.de/
582
583	=cut
584
585	1
586