[ViewVC] Diff of: cvs/AnyEvent-MP/MP.pm

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.6 by root, Sat Aug 1 10:02:33 2009 UTC vs.
Revision 1.32 by root, Wed Aug 5 19:58:46 2009 UTC

…		…
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use AnyEvent::MP;	7	use AnyEvent::MP;
8		8
9	NODE # returns this node identifier
10	$NODE # contains this node identifier	9	$NODE # contains this node's noderef
		10	NODE # returns this node's noderef
		11	NODE $port # returns the noderef of the port
11		12
12	snd $port, type => data...;	13	snd $port, type => data...;
		14
		15	$SELF # receiving/own port id in rcv callbacks
13		16
14	rcv $port, smartmatch => $cb->($port, @msg);	17	rcv $port, smartmatch => $cb->($port, @msg);
15		18
16	# examples:	19	# examples:
17	rcv $port2, ping => sub { snd $_[0], "pong"; 0 };	20	rcv $port2, ping => sub { snd $_[0], "pong"; 0 };
…		…
27	This module (-family) implements a simple message passing framework.	30	This module (-family) implements a simple message passing framework.
28		31
29	Despite its simplicity, you can securely message other processes running	32	Despite its simplicity, you can securely message other processes running
30	on the same or other hosts.	33	on the same or other hosts.
31		34
		35	For an introduction to this module family, see the L<AnyEvent::MP::Intro>
		36	manual page.
		37
32	At the moment, this module family is severly brokena nd underdocumented,	38	At the moment, this module family is severly broken and underdocumented,
33	so do not use. This was uploaded mainly to resreve the CPAN namespace -	39	so do not use. This was uploaded mainly to reserve the CPAN namespace -
34	stay tuned!	40	stay tuned! The basic API should be finished, however.
35		41
36	=head1 CONCEPTS	42	=head1 CONCEPTS
37		43
38	=over 4	44	=over 4
39		45
40	=item port	46	=item port
41		47
42	A port is something you can send messages to with the C<snd> function, and	48	A port is something you can send messages to (with the C<snd> function).
43	you can register C<rcv> handlers with. All C<rcv> handlers will receive	49
44	messages they match, messages will not be queued.	50	Some ports allow you to register C<rcv> handlers that can match specific
		51	messages. All C<rcv> handlers will receive messages they match, messages
		52	will not be queued.
45		53
46	=item port id - C<noderef#portname>	54	=item port id - C<noderef#portname>
47		55
48	A port id is always the noderef, a hash-mark (C<#>) as separator, followed	56	A port id is normaly the concatenation of a noderef, a hash-mark (C<#>) as
49	by a port name (a printable string of unspecified format).	57	separator, and a port name (a printable string of unspecified format). An
		58	exception is the the node port, whose ID is identical to its node
		59	reference.
50		60
51	=item node	61	=item node
52		62
53	A node is a single process containing at least one port - the node	63	A node is a single process containing at least one port - the node
54	port. You can send messages to node ports to let them create new ports,	64	port. You can send messages to node ports to find existing ports or to
55	among other things.	65	create new ports, among other things.
56		66
57	Initially, nodes are either private (single-process only) or hidden	67	Nodes are either private (single-process only), slaves (connected to a
58	(connected to a master node only). Only when they epxlicitly "become	68	master node only) or public nodes (connectable from unrelated nodes).
59	public" can you send them messages from unrelated other nodes.
60		69
61	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>	70	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>
62		71
63	A noderef is a string that either uniquely identifies a given node (for	72	A node reference is a string that either simply identifies the node (for
64	private and hidden nodes), or contains a recipe on how to reach a given	73	private and slave nodes), or contains a recipe on how to reach a given
65	node (for public nodes).	74	node (for public nodes).
66		75
		76	This recipe is simply a comma-separated list of C<address:port> pairs (for
		77	TCP/IP, other protocols might look different).
		78
		79	Node references come in two flavours: resolved (containing only numerical
		80	addresses) or unresolved (where hostnames are used instead of addresses).
		81
		82	Before using an unresolved node reference in a message you first have to
		83	resolve it.
		84
67	=back	85	=back
68		86
69	=head1 VARIABLES/FUNCTIONS	87	=head1 VARIABLES/FUNCTIONS
70		88
71	=over 4	89	=over 4
72		90
73	=cut	91	=cut
74		92
75	package AnyEvent::MP;	93	package AnyEvent::MP;
76		94
77	use AnyEvent::MP::Util ();
78	use AnyEvent::MP::Node;	95	use AnyEvent::MP::Base;
79	use AnyEvent::MP::Transport;
80		96
81	use utf8;
82	use common::sense;	97	use common::sense;
83		98
84	use Carp ();	99	use Carp ();
85		100
86	use AE ();	101	use AE ();
87		102
88	use base "Exporter";	103	use base "Exporter";
89		104
90	our $VERSION = '0.01';	105	our $VERSION = '0.1';
91	our @EXPORT = qw(NODE $NODE $PORT snd rcv _any_);	106	our @EXPORT = qw(
		107	NODE $NODE *SELF node_of _any_
		108	resolve_node initialise_node
		109	snd rcv mon kil reg psub
		110	port
		111	);
92		112
93	our $DEFAULT_SECRET;	113	our $SELF;
94	our $DEFAULT_PORT = "4040";
95		114
96	our $CONNECT_INTERVAL = 5; # new connect every 5s, at least	115	sub _self_die() {
97	our $CONNECT_TIMEOUT = 30; # includes handshake	116	my $msg = $@;
98		117	$msg =~ s/\n+$// unless ref $msg;
99	sub default_secret {	118	kil $SELF, die => $msg;
100	unless (defined $DEFAULT_SECRET) {
101	if (open my $fh, "<$ENV{HOME}/.aemp-secret") {
102	sysread $fh, $DEFAULT_SECRET, -s $fh;
103	} else {
104	$DEFAULT_SECRET = AnyEvent::MP::Util::nonce 32;
105	}
106	}
107
108	$DEFAULT_SECRET
109	}	119	}
110		120
111	=item NODE / $NODE	121	=item $thisnode = NODE / $NODE
112		122
113	The C<NODE ()> function and the C<$NODE> variable contain the noderef of	123	The C<NODE> function returns, and the C<$NODE> variable contains
114	the local node. The value is initialised by a call to C<become_public> or	124	the noderef of the local node. The value is initialised by a call
115	C<become_slave>, after which all local port identifiers become invalid.	125	to C<become_public> or C<become_slave>, after which all local port
		126	identifiers become invalid.
116		127
117	=cut	128	=item $noderef = node_of $portid
118		129
119	our $UNIQ = sprintf "%x.%x", $$, time; # per-process/node unique cookie	130	Extracts and returns the noderef from a portid or a noderef.
120	our $ID = "a0";
121	our $PUBLIC = 0;
122	our $NODE;
123	our $PORT;
124		131
125	our %NODE; # node id to transport mapping, or "undef", for local node	132	=item $cv = resolve_node $noderef
126	our %PORT; # local ports
127	our %LISTENER; # local transports
128		133
129	sub NODE() { $NODE }	134	Takes an unresolved node reference that may contain hostnames and
		135	abbreviated IDs, resolves all of them and returns a resolved node
		136	reference.
130		137
131	{	138	In addition to C<address:port> pairs allowed in resolved noderefs, the
132	use POSIX ();	139	following forms are supported:
133	my $nodename = (POSIX::uname)[1];
134	$NODE = "$$\@$nodename";
135	}
136		140
137	sub _ANY_() { 1 }	141	=over 4
138	sub _any_() { \&_ANY_ }
139		142
140	sub add_node {	143	=item the empty string
141	my ($noderef) = @_;
142		144
143	return $NODE{$noderef}	145	An empty-string component gets resolved as if the default port (4040) was
144	if exists $NODE{$noderef};	146	specified.
145		147
146	for (split /,/, $noderef) {	148	=item naked port numbers (e.g. C<1234>)
147	return $NODE{$noderef} = $NODE{$_}
148	if exists $NODE{$_};
149	}
150		149
151	# for indirect sends, use a different class	150	These are resolved by prepending the local nodename and a colon, to be
152	my $node = new AnyEvent::MP::Node::Direct $noderef;	151	further resolved.
153		152
154	$NODE{$_} = $node	153	=item hostnames (e.g. C<localhost:1234>, C<localhost>)
155	for $noderef, split /,/, $noderef;
156		154
157	$node	155	These are resolved by using AnyEvent::DNS to resolve them, optionally
158	}	156	looking up SRV records for the C<aemp=4040> port, if no port was
		157	specified.
		158
		159	=back
		160
		161	=item $SELF
		162
		163	Contains the current port id while executing C<rcv> callbacks or C<psub>
		164	blocks.
		165
		166	=item SELF, %SELF, @SELF...
		167
		168	Due to some quirks in how perl exports variables, it is impossible to
		169	just export C<$SELF>, all the symbols called C<SELF> are exported by this
		170	module, but only C<$SELF> is currently used.
159		171
160	=item snd $portid, type => @data	172	=item snd $portid, type => @data
161		173
162	=item snd $portid, @msg	174	=item snd $portid, @msg
163		175
164	Send the given message to the given port ID, which can identify either a	176	Send the given message to the given port ID, which can identify either
165	local or a remote port.	177	a local or a remote port, and can be either a string or soemthignt hat
		178	stringifies a sa port ID (such as a port object :).
166		179
167	While the message can be about anything, it is highly recommended to use	180	While the message can be about anything, it is highly recommended to use a
168	a constant string as first element.	181	string as first element (a portid, or some word that indicates a request
		182	type etc.).
169		183
170	The message data effectively becomes read-only after a call to this	184	The message data effectively becomes read-only after a call to this
171	function: modifying any argument is not allowed and can cause many	185	function: modifying any argument is not allowed and can cause many
172	problems.	186	problems.
173		187
…		…
175	JSON is used, then only strings, numbers and arrays and hashes consisting	189	JSON is used, then only strings, numbers and arrays and hashes consisting
176	of those are allowed (no objects). When Storable is used, then anything	190	of those are allowed (no objects). When Storable is used, then anything
177	that Storable can serialise and deserialise is allowed, and for the local	191	that Storable can serialise and deserialise is allowed, and for the local
178	node, anything can be passed.	192	node, anything can be passed.
179		193
180	=cut	194	=item $local_port = port
181		195
182	sub snd(@) {	196	Create a new local port object that can be used either as a pattern
183	my ($noderef, $port) = split /#/, shift, 2;	197	matching port ("full port") or a single-callback port ("miniport"),
		198	depending on how C<rcv> callbacks are bound to the object.
184		199
185	add_node $noderef	200	=item $portid = port { my @msg = @_; $finished }
186	unless exists $NODE{$noderef};
187		201
188	$NODE{$noderef}->send (["$port", [@_]]);	202	Creates a "mini port", that is, a very lightweight port without any
		203	pattern matching behind it, and returns its ID.
		204
		205	The block will be called for every message received on the port. When the
		206	callback returns a true value its job is considered "done" and the port
		207	will be destroyed. Otherwise it will stay alive.
		208
		209	The message will be passed as-is, no extra argument (i.e. no port id) will
		210	be passed to the callback.
		211
		212	If you need the local port id in the callback, this works nicely:
		213
		214	my $port; $port = port {
		215	snd $otherport, reply => $port;
		216	};
		217
		218	=cut
		219
		220	sub port(;&) {
		221	my $id = "$UNIQ." . $ID++;
		222	my $port = "$NODE#$id";
		223
		224	if (@_) {
		225	my $cb = shift;
		226	$PORT{$id} = sub {
		227	local $SELF = $port;
		228	eval {
		229	&$cb
		230	and kil $id;
		231	};
		232	_self_die if $@;
		233	};
		234	} else {
		235	my $self = bless {
		236	id => "$NODE#$id",
		237	}, "AnyEvent::MP::Port";
		238
		239	$PORT_DATA{$id} = $self;
		240	$PORT{$id} = sub {
		241	local $SELF = $port;
		242
		243	eval {
		244	for (@{ $self->{rc0}{$_[0]} }) {
		245	$_ && &{$_->[0]}
		246	&& undef $_;
		247	}
		248
		249	for (@{ $self->{rcv}{$_[0]} }) {
		250	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
		251	&& &{$_->[0]}
		252	&& undef $_;
		253	}
		254
		255	for (@{ $self->{any} }) {
		256	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
		257	&& &{$_->[0]}
		258	&& undef $_;
		259	}
		260	};
		261	_self_die if $@;
		262	};
		263	}
		264
		265	$port
189	}	266	}
190		267
		268	=item reg $portid, $name
		269
		270	Registers the given port under the name C<$name>. If the name already
		271	exists it is replaced.
		272
		273	A port can only be registered under one well known name.
		274
		275	A port automatically becomes unregistered when it is killed.
		276
		277	=cut
		278
		279	sub reg(@) {
		280	my ($portid, $name) = @_;
		281
		282	$REG{$name} = $portid;
		283	}
		284
191	=item rcv $portid, type => $callback->(@msg)	285	=item rcv $portid, $callback->(@msg)
192		286
		287	Replaces the callback on the specified miniport (or newly created port
		288	object, see C<port>). Full ports are configured with the following calls:
		289
		290	=item rcv $portid, tagstring => $callback->(@msg), ...
		291
193	=item rcv $portid, $smartmatch => $callback->(@msg)	292	=item rcv $portid, $smartmatch => $callback->(@msg), ...
194		293
195	=item rcv $portid, [$smartmatch...] => $callback->(@msg)	294	=item rcv $portid, [$smartmatch...] => $callback->(@msg), ...
196		295
197	Register a callback on the port identified by C<$portid>, which I<must> be	296	Register callbacks to be called on matching messages on the given full
198	a local port.	297	port (or newly created port).
199		298
200	The callback has to return a true value when its work is done, after	299	The callback has to return a true value when its work is done, after
201	which is will be removed, or a false value in which case it will stay	300	which is will be removed, or a false value in which case it will stay
202	registered.	301	registered.
203		302
		303	The global C<$SELF> (exported by this module) contains C<$portid> while
		304	executing the callback.
		305
		306	Runtime errors wdurign callback execution will result in the port being
		307	C<kil>ed.
		308
204	If the match is an array reference, then it will be matched against the	309	If the match is an array reference, then it will be matched against the
205	first elements of the message, otherwise only the first element is being	310	first elements of the message, otherwise only the first element is being
206	matched.	311	matched.
207		312
208	Any element in the match that is specified as C<_any_> (a function	313	Any element in the match that is specified as C<_any_> (a function
…		…
213	also the most efficient match (by far).	318	also the most efficient match (by far).
214		319
215	=cut	320	=cut
216		321
217	sub rcv($@) {	322	sub rcv($@) {
218	my ($port, $match, $cb) = @_;	323	my $portid = shift;
219
220	my $port = $PORT{$port}
221	or do {
222	my ($noderef, $lport) = split /#/, $port;	324	my ($noderef, $port) = split /#/, $port, 2;
223	"AnyEvent::MP::Node::Self" eq ref $NODE{$noderef}	325
		326	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}
224	or Carp::croak "$port: can only rcv on local ports";	327	or Carp::croak "$noderef#$port: rcv can only be called on local ports, caught";
225		328
226	$PORT{$lport}	329	my $self = $PORT_DATA{$port}
227	or Carp::croak "$port: port does not exist";	330	or Carp::croak "$noderef#$port: rcv can only be called on message matching ports, caught";
228		331
229	$PORT{$port} = $PORT{$lport} # also return	332	"AnyEvent::MP::Port" eq ref $self
		333	or Carp::croak "$noderef#$port: rcv can only be called on message matching ports, caught";
		334
		335	while (@_) {
		336	my ($match, $cb) = splice @_, 0, 2;
		337
		338	if (!ref $match) {
		339	push @{ $self->{rc0}{$match} }, [$cb];
		340	} elsif (("ARRAY" eq ref $match && !ref $match->[0])) {
		341	my ($type, @match) = @$match;
		342	@match
		343	? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match]
		344	: push @{ $self->{rc0}{$match->[0]} }, [$cb];
		345	} else {
		346	push @{ $self->{any} }, [$cb, $match];
		347	}
		348	}
		349
		350	$portid
		351	}
		352
		353	=item $closure = psub { BLOCK }
		354
		355	Remembers C<$SELF> and creates a closure out of the BLOCK. When the
		356	closure is executed, sets up the environment in the same way as in C<rcv>
		357	callbacks, i.e. runtime errors will cause the port to get C<kil>ed.
		358
		359	This is useful when you register callbacks from C<rcv> callbacks:
		360
		361	rcv delayed_reply => sub {
		362	my ($delay, @reply) = @_;
		363	my $timer = AE::timer $delay, 0, psub {
		364	snd @reply, $SELF;
230	};	365	};
		366	};
231		367
232	if (!ref $match) {	368	=cut
233	push @{ $port->{rc0}{$match} }, [$cb];	369
234	} elsif (("ARRAY" eq ref $match && !ref $match->[0])) {	370	sub psub(&) {
235	my ($type, @match) = @$match;	371	my $cb = shift;
236	@match	372
237	? push @{ $port->{rcv}{$match->[0]} }, [$cb, \@match]	373	my $port = $SELF
238	: push @{ $port->{rc0}{$match->[0]} }, [$cb];	374	or Carp::croak "psub can only be called from within rcv or psub callbacks, not";
		375
		376	sub {
		377	local $SELF = $port;
		378
		379	if (wantarray) {
		380	my @res = eval { &$cb };
		381	_self_die if $@;
		382	@res
239	} else {	383	} else {
240	push @{ $port->{any} }, [$cb, $match];	384	my $res = eval { &$cb };
		385	_self_die if $@;
		386	$res
		387	}
241	}	388	}
242	}	389	}
243		390
244	sub _inject {	391	=item $guard = mon $portid, $cb->(@reason)
245	my ($port, $msg) = @{+shift};
246		392
247	$port = $PORT{$port}	393	=item $guard = mon $portid, $otherport
248	or return;
249		394
250	@_ = @$msg;	395	=item $guard = mon $portid, $otherport, @msg
251		396
252	for (@{ $port->{rc0}{$msg->[0]} }) {	397	Monitor the given port and do something when the port is killed.
253	$_ && &{$_->[0]}
254	&& undef $_;
255	}
256		398
257	for (@{ $port->{rcv}{$msg->[0]} }) {	399	In the first form, the callback is simply called with any number
258	$_ && [@_[1..$#{$_->[1]}]] ~~ $_->[1]	400	of C<@reason> elements (no @reason means that the port was deleted
259	&& &{$_->[0]}	401	"normally"). Note also that I<< the callback B<must> never die >>, so use
260	&& undef $_;	402	C<eval> if unsure.
261	}
262		403
263	for (@{ $port->{any} }) {	404	In the second form, the other port will be C<kil>'ed with C<@reason>, iff
264	$_ && [@_[0..$#{$_->[1]}]] ~~ $_->[1]	405	a @reason was specified, i.e. on "normal" kils nothing happens, while
265	&& &{$_->[0]}	406	under all other conditions, the other port is killed with the same reason.
266	&& undef $_;
267	}
268	}
269		407
270	sub normalise_noderef($) {	408	In the last form, a message of the form C<@msg, @reason> will be C<snd>.
271	my ($noderef) = @_;
272		409
273	my $cv = AE::cv;	410	Example: call a given callback when C<$port> is killed.
274	my @res;
275		411
276	$cv->begin (sub {	412	mon $port, sub { warn "port died because of <@_>\n" };
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 (join ",", @refs);
283	});
284		413
285	$noderef = $DEFAULT_PORT unless length $noderef;	414	Example: kill ourselves when C<$port> is killed abnormally.
286		415
287	my $idx;	416	mon $port, $self;
288	for my $t (split /,/, $noderef) {
289	my $pri = ++$idx;
290
291	#TODO: this should be outside normalise_noderef and in become_public
292	if ($t =~ /^\d*$/) {
293	my $nodename = (POSIX::uname)[1];
294		417
295	$cv->begin;	418	Example: send us a restart message another C<$port> is killed.
296	AnyEvent::Socket::resolve_sockaddr $nodename, $t \|\| "aemp=$DEFAULT_PORT", "tcp", 0, undef, sub {	419
		420	mon $port, $self => "restart";
		421
		422	=cut
		423
		424	sub mon {
		425	my ($noderef, $port) = split /#/, shift, 2;
		426
		427	my $node = $NODE{$noderef} \|\| add_node $noderef;
		428
		429	my $cb = shift;
		430
		431	unless (ref $cb) {
297	for (@_) {	432	if (@_) {
298	my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3];	433	# send a kill info message
299	push @res, [	434	my (@msg) = ($cb, @_);
300	$pri += 1e-5,	435	$cb = sub { snd @msg, @_ };
301	AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service
302	];
303	}
304	$cv->end;
305	};
306
307	# my (undef, undef, undef, undef, @ipv4) = gethostbyname $nodename;
308	#
309	# for (@ipv4) {
310	# push @res, [
311	# $pri,
312	# AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $_, $t \|\| $DEFAULT_PORT,
313	# ];
314	# }
315	} else {	436	} else {
316	my ($host, $port) = AnyEvent::Socket::parse_hostport $t, "aemp=$DEFAULT_PORT"	437	# simply kill other port
317	or Carp::croak "$t: unparsable transport descriptor";	438	my $port = $cb;
318		439	$cb = sub { kil $port, @_ if @_ };
319	$cv->begin;
320	AnyEvent::Socket::resolve_sockaddr $host, $port, "tcp", 0, undef, sub {
321	for (@_) {
322	my ($service, $host) = AnyEvent::Socket::unpack_sockaddr $_->[3];
323	push @res, [
324	$pri += 1e-5,
325	AnyEvent::Socket::format_hostport AnyEvent::Socket::format_address $host, $service
326	];
327	}
328	$cv->end;
329	}
330	}	440	}
331	}	441	}
332		442
333	$cv->end;	443	$node->monitor ($port, $cb);
334		444
335	$cv	445	defined wantarray
		446	and AnyEvent::Util::guard { $node->unmonitor ($port, $cb) }
336	}	447	}
337		448
338	sub become_public {	449	=item $guard = mon_guard $port, $ref, $ref...
339	return if $PUBLIC;
340		450
341	my $noderef = join ",", ref $_[0] ? @{+shift} : shift;	451	Monitors the given C<$port> and keeps the passed references. When the port
342	my @args = @_;	452	is killed, the references will be freed.
343		453
344	$NODE = (normalise_noderef $noderef)->recv;	454	Optionally returns a guard that will stop the monitoring.
345		455
346	for my $t (split /,/, $NODE) {	456	This function is useful when you create e.g. timers or other watchers and
347	$NODE{$t} = $NODE{""};	457	want to free them when the port gets killed:
348		458
349	my ($host, $port) = AnyEvent::Socket::parse_hostport $t;	459	$port->rcv (start => sub {
350		460	my $timer; $timer = mon_guard $port, AE::timer 1, 1, sub {
351	$LISTENER{$t} = AnyEvent::MP::Transport::mp_server $host, $port,	461	undef $timer if 0.9 < rand;
352	@args,
353	on_error => sub {
354	die "on_error<@_>\n";#d#
355	},
356	on_connect => sub {
357	my ($tp) = @_;
358
359	$NODE{$tp->{remote_id}} = $_[0];
360	},
361	sub {
362	my ($tp) = @_;
363
364	$NODE{"$tp->{peerhost}:$tp->{peerport}"} = $tp;
365	},
366	;	462	});
367	}	463	});
368		464
369	$PUBLIC = 1;	465	=cut
		466
		467	sub mon_guard {
		468	my ($port, @refs) = @_;
		469
		470	mon $port, sub { 0 && @refs }
370	}	471	}
		472
		473	=item lnk $port1, $port2
		474
		475	Link two ports. This is simply a shorthand for:
		476
		477	mon $port1, $port2;
		478	mon $port2, $port1;
		479
		480	It means that if either one is killed abnormally, the other one gets
		481	killed as well.
		482
		483	=item kil $portid[, @reason]
		484
		485	Kill the specified port with the given C<@reason>.
		486
		487	If no C<@reason> is specified, then the port is killed "normally" (linked
		488	ports will not be kileld, or even notified).
		489
		490	Otherwise, linked ports get killed with the same reason (second form of
		491	C<mon>, see below).
		492
		493	Runtime errors while evaluating C<rcv> callbacks or inside C<psub> blocks
		494	will be reported as reason C<< die => $@ >>.
		495
		496	Transport/communication errors are reported as C<< transport_error =>
		497	$message >>.
		498
		499	=back
		500
		501	=head1 FUNCTIONS FOR NODES
		502
		503	=over 4
		504
		505	=item become_public $noderef
		506
		507	Tells the node to become a public node, i.e. reachable from other nodes.
		508
		509	The first argument is the (unresolved) node reference of the local node
		510	(if missing then the empty string is used).
		511
		512	It is quite common to not specify anything, in which case the local node
		513	tries to listen on the default port, or to only specify a port number, in
		514	which case AnyEvent::MP tries to guess the local addresses.
		515
		516	=cut
371		517
372	=back	518	=back
373		519
374	=head1 NODE MESSAGES	520	=head1 NODE MESSAGES
375		521
376	Nodes understand the following messages sent to them. Many of them take	522	Nodes understand the following messages sent to them. Many of them take
377	arguments called C<@reply>, which will simply be used to compose a reply	523	arguments called C<@reply>, which will simply be used to compose a reply
378	message - C<$reply[0]> is the port to reply to, C<$reply[1]> the type and	524	message - C<$reply[0]> is the port to reply to, C<$reply[1]> the type and
379	the remaining arguments are simply the message data.	525	the remaining arguments are simply the message data.
380		526
		527	While other messages exist, they are not public and subject to change.
		528
381	=over 4	529	=over 4
382		530
383	=cut	531	=cut
384		532
385	#############################################################################	533	=item lookup => $name, @reply
386	# self node code
387		534
388	sub _new_port($) {	535	Replies with the port ID of the specified well-known port, or C<undef>.
389	my ($name) = @_;
390		536
391	my ($noderef, $portname) = split /#/, $name;	537	=item devnull => ...
392		538
393	$PORT{$name} =	539	Generic data sink/CPU heat conversion.
394	$PORT{$portname} = {
395	names => [$name, $portname],
396	};
397	}
398
399	$NODE{""} = new AnyEvent::MP::Node::Self noderef => $NODE;
400	_new_port "";
401		540
402	=item relay => $port, @msg	541	=item relay => $port, @msg
403		542
404	Simply forwards the message to the given port.	543	Simply forwards the message to the given port.
405
406	=cut
407
408	rcv "", relay => \&snd;
409		544
410	=item eval => $string[ @reply]	545	=item eval => $string[ @reply]
411		546
412	Evaluates the given string. If C<@reply> is given, then a message of the	547	Evaluates the given string. If C<@reply> is given, then a message of the
413	form C<@reply, $@, @evalres> is sent.	548	form C<@reply, $@, @evalres> is sent.
414		549
415	Example: crash another node.	550	Example: crash another node.
416		551
417	snd $othernode, eval => "exit";	552	snd $othernode, eval => "exit";
418		553
419	=cut
420
421	rcv "", eval => sub {
422	my (undef, $string, @reply) = @_;
423	my @res = eval $string;
424	snd @reply, "$@", @res if @reply;
425	};
426
427	=item time => @reply	554	=item time => @reply
428		555
429	Replies the the current node time to C<@reply>.	556	Replies the the current node time to C<@reply>.
430		557
431	Example: tell the current node to send the current time to C<$myport> in a	558	Example: tell the current node to send the current time to C<$myport> in a
432	C<timereply> message.	559	C<timereply> message.
433		560
434	snd $NODE, time => $myport, timereply => 1, 2;	561	snd $NODE, time => $myport, timereply => 1, 2;
435	# => snd $myport, timereply => 1, 2, <time>	562	# => snd $myport, timereply => 1, 2, <time>
436		563
437	=cut	564	=back
438		565
439	rcv "", time => sub { shift; snd @_, AE::time };	566	=head1 AnyEvent::MP vs. Distributed Erlang
		567
		568	AnyEvent::MP got lots of its ideas from distributed erlang (erlang node
		569	== aemp node, erlang process == aemp port), so many of the documents and
		570	programming techniques employed by erlang apply to AnyEvent::MP. Here is a
		571	sample:
		572
		573	http://www.erlang.se/doc/programming_rules.shtml
		574	http://erlang.org/doc/getting_started/part_frame.html # chapters 3 and 4
		575	http://erlang.org/download/erlang-book-part1.pdf # chapters 5 and 6
		576	http://erlang.org/download/armstrong_thesis_2003.pdf # chapters 4 and 5
		577
		578	Despite the similarities, there are also some important differences:
		579
		580	=over 4
		581
		582	=item * Node references contain the recipe on how to contact them.
		583
		584	Erlang relies on special naming and DNS to work everywhere in the
		585	same way. AEMP relies on each node knowing it's own address(es), with
		586	convenience functionality.
		587
		588	This means that AEMP requires a less tightly controlled environment at the
		589	cost of longer node references and a slightly higher management overhead.
		590
		591	=item * Erlang uses processes and a mailbox, AEMP does not queue.
		592
		593	Erlang uses processes that selctively receive messages, and therefore
		594	needs a queue. AEMP is event based, queuing messages would serve no useful
		595	purpose.
		596
		597	(But see L<Coro::MP> for a more erlang-like process model on top of AEMP).
		598
		599	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
		600
		601	Sending messages in erlang is synchronous and blocks the process. AEMP
		602	sends are immediate, connection establishment is handled in the
		603	background.
		604
		605	=item * Erlang can silently lose messages, AEMP cannot.
		606
		607	Erlang makes few guarantees on messages delivery - messages can get lost
		608	without any of the processes realising it (i.e. you send messages a, b,
		609	and c, and the other side only receives messages a and c).
		610
		611	AEMP guarantees correct ordering, and the guarantee that there are no
		612	holes in the message sequence.
		613
		614	=item * In erlang, processes can be declared dead and later be found to be
		615	alive.
		616
		617	In erlang it can happen that a monitored process is declared dead and
		618	linked processes get killed, but later it turns out that the process is
		619	still alive - and can receive messages.
		620
		621	In AEMP, when port monitoring detects a port as dead, then that port will
		622	eventually be killed - it cannot happen that a node detects a port as dead
		623	and then later sends messages to it, finding it is still alive.
		624
		625	=item * Erlang can send messages to the wrong port, AEMP does not.
		626
		627	In erlang it is quite possible that a node that restarts reuses a process
		628	ID known to other nodes for a completely different process, causing
		629	messages destined for that process to end up in an unrelated process.
		630
		631	AEMP never reuses port IDs, so old messages or old port IDs floating
		632	around in the network will not be sent to an unrelated port.
		633
		634	=item * Erlang uses unprotected connections, AEMP uses secure
		635	authentication and can use TLS.
		636
		637	AEMP can use a proven protocol - SSL/TLS - to protect connections and
		638	securely authenticate nodes.
		639
		640	=item * The AEMP protocol is optimised for both text-based and binary
		641	communications.
		642
		643	The AEMP protocol, unlike the erlang protocol, supports both
		644	language-independent text-only protocols (good for debugging) and binary,
		645	language-specific serialisers (e.g. Storable).
		646
		647	It has also been carefully designed to be implementable in other languages
		648	with a minimum of work while gracefully degrading fucntionality to make the
		649	protocol simple.
440		650
441	=back	651	=back
442		652
443	=head1 SEE ALSO	653	=head1 SEE ALSO
444		654

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing AnyEvent-MP/MP.pm (file contents): Revision 1.6 by root, Sat Aug 1 10:02:33 2009 UTC vs. Revision 1.32 by root, Wed Aug 5 19:58:46 2009 UTC

Diff Legend

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.6 by root, Sat Aug 1 10:02:33 2009 UTC vs.
Revision 1.32 by root, Wed Aug 5 19:58:46 2009 UTC