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

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs.
Revision 1.55 by root, Fri Aug 14 23:17:17 2009 UTC

…		…
22	# sending messages	22	# sending messages
23	snd $port, type => data...;	23	snd $port, type => data...;
24	snd $port, @msg;	24	snd $port, @msg;
25	snd @msg_with_first_element_being_a_port;	25	snd @msg_with_first_element_being_a_port;
26		26
27	# creating/using miniports	27	# creating/using ports, the simple way
28	my $miniport = port { my @msg = @_; 0 };	28	my $simple_port = port { my @msg = @_; 0 };
29		29
30	# creating/using full ports	30	# creating/using ports, tagged message matching
31	my $port = port;	31	my $port = port;
32	rcv $port, smartmatch => $cb->(@msg);
33	rcv $port, ping => sub { snd $_[0], "pong"; 0 };	32	rcv $port, ping => sub { snd $_[0], "pong"; 0 };
34	rcv $port, pong => sub { warn "pong received\n"; 0 };	33	rcv $port, pong => sub { warn "pong received\n"; 0 };
35
36	# more, smarter, matches (_any_ is exported by this module)
37	rcv $port, [child_died => $pid] => sub { ...
38	rcv $port, [_any_, _any_, 3] => sub { .. $_[2] is 3
39		34
40	# create a port on another node	35	# create a port on another node
41	my $port = spawn $node, $initfunc, @initdata;	36	my $port = spawn $node, $initfunc, @initdata;
42		37
43	# monitoring	38	# monitoring
…		…
74		69
75	=item port	70	=item port
76		71
77	A port is something you can send messages to (with the C<snd> function).	72	A port is something you can send messages to (with the C<snd> function).
78		73
79	Some ports allow you to register C<rcv> handlers that can match specific	74	Ports allow you to register C<rcv> handlers that can match all or just
80	messages. All C<rcv> handlers will receive messages they match, messages	75	some messages. Messages will not be queued.
81	will not be queued.
82		76
83	=item port id - C<noderef#portname>	77	=item port id - C<noderef#portname>
84		78
85	A port id is normaly the concatenation of a noderef, a hash-mark (C<#>) as	79	A port ID is the concatenation of a noderef, a hash-mark (C<#>) as
86	separator, and a port name (a printable string of unspecified format). An	80	separator, and a port name (a printable string of unspecified format). An
87	exception is the the node port, whose ID is identical to its node	81	exception is the the node port, whose ID is identical to its node
88	reference.	82	reference.
89		83
90	=item node	84	=item node
91		85
92	A node is a single process containing at least one port - the node	86	A node is a single process containing at least one port - the node port,
93	port. You can send messages to node ports to find existing ports or to	87	which provides nodes to manage each other remotely, and to create new
94	create new ports, among other things.	88	ports.
95		89
96	Nodes are either private (single-process only), slaves (connected to a	90	Nodes are either private (single-process only), slaves (connected to a
97	master node only) or public nodes (connectable from unrelated nodes).	91	master node only) or public nodes (connectable from unrelated nodes).
98		92
99	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>	93	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>
…		…
148	kil $SELF, die => $msg;	142	kil $SELF, die => $msg;
149	}	143	}
150		144
151	=item $thisnode = NODE / $NODE	145	=item $thisnode = NODE / $NODE
152		146
153	The C<NODE> function returns, and the C<$NODE> variable contains	147	The C<NODE> function returns, and the C<$NODE> variable contains the
154	the noderef of the local node. The value is initialised by a call	148	noderef of the local node. The value is initialised by a call to
155	to C<become_public> or C<become_slave>, after which all local port	149	C<initialise_node>.
156	identifiers become invalid.
157		150
158	=item $noderef = node_of $port	151	=item $noderef = node_of $port
159		152
160	Extracts and returns the noderef from a portid or a noderef.	153	Extracts and returns the noderef from a port ID or a noderef.
161		154
162	=item initialise_node $noderef, $seednode, $seednode...	155	=item initialise_node $noderef, $seednode, $seednode...
163		156
164	=item initialise_node "slave/", $master, $master...	157	=item initialise_node "slave/", $master, $master...
165		158
…		…
168	it should know the noderefs of some other nodes in the network.	161	it should know the noderefs of some other nodes in the network.
169		162
170	This function initialises a node - it must be called exactly once (or	163	This function initialises a node - it must be called exactly once (or
171	never) before calling other AnyEvent::MP functions.	164	never) before calling other AnyEvent::MP functions.
172		165
173	All arguments are noderefs, which can be either resolved or unresolved.	166	All arguments (optionally except for the first) are noderefs, which can be
		167	either resolved or unresolved.
		168
		169	The first argument will be looked up in the configuration database first
		170	(if it is C<undef> then the current nodename will be used instead) to find
		171	the relevant configuration profile (see L<aemp>). If none is found then
		172	the default configuration is used. The configuration supplies additional
		173	seed/master nodes and can override the actual noderef.
174		174
175	There are two types of networked nodes, public nodes and slave nodes:	175	There are two types of networked nodes, public nodes and slave nodes:
176		176
177	=over 4	177	=over 4
178		178
179	=item public nodes	179	=item public nodes
180		180
181	For public nodes, C<$noderef> must either be a (possibly unresolved)	181	For public nodes, C<$noderef> (supplied either directly to
182	noderef, in which case it will be resolved, or C<undef> (or missing), in	182	C<initialise_node> or indirectly via a profile or the nodename) must be a
183	which case the noderef will be guessed.	183	noderef (possibly unresolved, in which case it will be resolved).
184		184
185	Afterwards, the node will bind itself on all endpoints and try to connect	185	After resolving, the node will bind itself on all endpoints and try to
186	to all additional C<$seednodes> that are specified. Seednodes are optional	186	connect to all additional C<$seednodes> that are specified. Seednodes are
187	and can be used to quickly bootstrap the node into an existing network.	187	optional and can be used to quickly bootstrap the node into an existing
		188	network.
188		189
189	=item slave nodes	190	=item slave nodes
190		191
191	When the C<$noderef> is the special string C<slave/>, then the node will	192	When the C<$noderef> (either as given or overriden by the config file)
		193	is the special string C<slave/>, then the node will become a slave
192	become a slave node. Slave nodes cannot be contacted from outside and will	194	node. Slave nodes cannot be contacted from outside and will route most of
193	route most of their traffic to the master node that they attach to.	195	their traffic to the master node that they attach to.
194		196
195	At least one additional noderef is required: The node will try to connect	197	At least one additional noderef is required (either by specifying it
196	to all of them and will become a slave attached to the first node it can	198	directly or because it is part of the configuration profile): The node
197	successfully connect to.	199	will try to connect to all of them and will become a slave attached to the
		200	first node it can successfully connect to.
198		201
199	=back	202	=back
200		203
201	This function will block until all nodes have been resolved and, for slave	204	This function will block until all nodes have been resolved and, for slave
202	nodes, until it has successfully established a connection to a master	205	nodes, until it has successfully established a connection to a master
203	server.	206	server.
204		207
205	Example: become a public node listening on the default node.	208	Example: become a public node listening on the guessed noderef, or the one
		209	specified via C<aemp> for the current node. This should be the most common
		210	form of invocation for "daemon"-type nodes.
206		211
207	initialise_node;	212	initialise_node;
		213
		214	Example: become a slave node to any of the the seednodes specified via
		215	C<aemp>. This form is often used for commandline clients.
		216
		217	initialise_node "slave/";
		218
		219	Example: become a slave node to any of the specified master servers. This
		220	form is also often used for commandline clients.
		221
		222	initialise_node "slave/", "master1", "192.168.13.17", "mp.example.net";
208		223
209	Example: become a public node, and try to contact some well-known master	224	Example: become a public node, and try to contact some well-known master
210	servers to become part of the network.	225	servers to become part of the network.
211		226
212	initialise_node undef, "master1", "master2";	227	initialise_node undef, "master1", "master2";
…		…
215		230
216	initialise_node 4041;	231	initialise_node 4041;
217		232
218	Example: become a public node, only visible on localhost port 4044.	233	Example: become a public node, only visible on localhost port 4044.
219		234
220	initialise_node "locahost:4044";	235	initialise_node "localhost:4044";
221
222	Example: become a slave node to any of the specified master servers.
223
224	initialise_node "slave/", "master1", "192.168.13.17", "mp.example.net";
225		236
226	=item $cv = resolve_node $noderef	237	=item $cv = resolve_node $noderef
227		238
228	Takes an unresolved node reference that may contain hostnames and	239	Takes an unresolved node reference that may contain hostnames and
229	abbreviated IDs, resolves all of them and returns a resolved node	240	abbreviated IDs, resolves all of them and returns a resolved node
…		…
266	=item snd $port, type => @data	277	=item snd $port, type => @data
267		278
268	=item snd $port, @msg	279	=item snd $port, @msg
269		280
270	Send the given message to the given port ID, which can identify either	281	Send the given message to the given port ID, which can identify either
271	a local or a remote port, and can be either a string or soemthignt hat	282	a local or a remote port, and must be a port ID.
272	stringifies a sa port ID (such as a port object :).
273		283
274	While the message can be about anything, it is highly recommended to use a	284	While the message can be about anything, it is highly recommended to use a
275	string as first element (a portid, or some word that indicates a request	285	string as first element (a port ID, or some word that indicates a request
276	type etc.).	286	type etc.).
277		287
278	The message data effectively becomes read-only after a call to this	288	The message data effectively becomes read-only after a call to this
279	function: modifying any argument is not allowed and can cause many	289	function: modifying any argument is not allowed and can cause many
280	problems.	290	problems.
…		…
285	that Storable can serialise and deserialise is allowed, and for the local	295	that Storable can serialise and deserialise is allowed, and for the local
286	node, anything can be passed.	296	node, anything can be passed.
287		297
288	=item $local_port = port	298	=item $local_port = port
289		299
290	Create a new local port object that can be used either as a pattern	300	Create a new local port object and returns its port ID. Initially it has
291	matching port ("full port") or a single-callback port ("miniport"),	301	no callbacks set and will throw an error when it receives messages.
292	depending on how C<rcv> callbacks are bound to the object.
293		302
294	=item $port = port { my @msg = @_; $finished }	303	=item $local_port = port { my @msg = @_ }
295		304
296	Creates a "miniport", that is, a very lightweight port without any pattern	305	Creates a new local port, and returns its ID. Semantically the same as
297	matching behind it, and returns its ID. Semantically the same as creating
298	a port and calling C<rcv $port, $callback> on it.	306	creating a port and calling C<rcv $port, $callback> on it.
299		307
300	The block will be called for every message received on the port. When the	308	The block will be called for every message received on the port, with the
301	callback returns a true value its job is considered "done" and the port	309	global variable C<$SELF> set to the port ID. Runtime errors will cause the
302	will be destroyed. Otherwise it will stay alive.	310	port to be C<kil>ed. The message will be passed as-is, no extra argument
		311	(i.e. no port ID) will be passed to the callback.
303		312
304	The message will be passed as-is, no extra argument (i.e. no port id) will	313	If you want to stop/destroy the port, simply C<kil> it:
305	be passed to the callback.
306		314
307	If you need the local port id in the callback, this works nicely:	315	my $port = port {
308		316	my @msg = @_;
309	my $port; $port = port {	317	...
310	snd $otherport, reply => $port;	318	kil $SELF;
311	};	319	};
312		320
313	=cut	321	=cut
314		322
315	sub rcv($@);	323	sub rcv($@);
		324
		325	sub _kilme {
		326	die "received message on port without callback";
		327	}
316		328
317	sub port(;&) {	329	sub port(;&) {
318	my $id = "$UNIQ." . $ID++;	330	my $id = "$UNIQ." . $ID++;
319	my $port = "$NODE#$id";	331	my $port = "$NODE#$id";
320		332
321	if (@_) {	333	rcv $port, shift \|\| \&_kilme;
322	rcv $port, shift;
323	} else {
324	$PORT{$id} = sub { }; # nop
325	}
326		334
327	$port	335	$port
328	}	336	}
329		337
330	=item reg $port, $name
331
332	=item reg $name
333
334	Registers the given port (or C<$SELF><<< if missing) under the name
335	C<$name>. If the name already exists it is replaced.
336
337	A port can only be registered under one well known name.
338
339	A port automatically becomes unregistered when it is killed.
340
341	=cut
342
343	sub reg(@) {
344	my $port = @_ > 1 ? shift : $SELF \|\| Carp::croak 'reg: called with one argument only, but $SELF not set,';
345
346	$REG{$_[0]} = $port;
347	}
348
349	=item rcv $port, $callback->(@msg)	338	=item rcv $local_port, $callback->(@msg)
350		339
351	Replaces the callback on the specified miniport (after converting it to	340	Replaces the default callback on the specified port. There is no way to
352	one if required).	341	remove the default callback: use C<sub { }> to disable it, or better
353		342	C<kil> the port when it is no longer needed.
354	=item rcv $port, tagstring => $callback->(@msg), ...
355
356	=item rcv $port, $smartmatch => $callback->(@msg), ...
357
358	=item rcv $port, [$smartmatch...] => $callback->(@msg), ...
359
360	Register callbacks to be called on matching messages on the given full
361	port (after converting it to one if required) and return the port.
362
363	The callback has to return a true value when its work is done, after
364	which is will be removed, or a false value in which case it will stay
365	registered.
366		343
367	The global C<$SELF> (exported by this module) contains C<$port> while	344	The global C<$SELF> (exported by this module) contains C<$port> while
368	executing the callback.	345	executing the callback. Runtime errors during callback execution will
		346	result in the port being C<kil>ed.
369		347
370	Runtime errors during callback execution will result in the port being	348	The default callback received all messages not matched by a more specific
371	C<kil>ed.	349	C<tag> match.
372		350
373	If the match is an array reference, then it will be matched against the	351	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
374	first elements of the message, otherwise only the first element is being
375	matched.
376		352
377	Any element in the match that is specified as C<_any_> (a function	353	Register (or replace) callbacks to be called on messages starting with the
378	exported by this module) matches any single element of the message.	354	given tag on the given port (and return the port), or unregister it (when
		355	C<$callback> is C<$undef> or missing). There can only be one callback
		356	registered for each tag.
379		357
380	While not required, it is highly recommended that the first matching	358	The original message will be passed to the callback, after the first
381	element is a string identifying the message. The one-string-only match is	359	element (the tag) has been removed. The callback will use the same
382	also the most efficient match (by far).	360	environment as the default callback (see above).
383		361
384	Example: create a port and bind receivers on it in one go.	362	Example: create a port and bind receivers on it in one go.
385		363
386	my $port = rcv port,	364	my $port = rcv port,
387	msg1 => sub { ...; 0 },	365	msg1 => sub { ... },
388	msg2 => sub { ...; 0 },	366	msg2 => sub { ... },
389	;	367	;
390		368
391	Example: create a port, bind receivers and send it in a message elsewhere	369	Example: create a port, bind receivers and send it in a message elsewhere
392	in one go:	370	in one go:
393		371
394	snd $otherport, reply =>	372	snd $otherport, reply =>
395	rcv port,	373	rcv port,
396	msg1 => sub { ...; 0 },	374	msg1 => sub { ... },
397	...	375	...
398	;	376	;
		377
		378	Example: temporarily register a rcv callback for a tag matching some port
		379	(e.g. for a rpc reply) and unregister it after a message was received.
		380
		381	rcv $port, $otherport => sub {
		382	my @reply = @_;
		383
		384	rcv $SELF, $otherport;
		385	};
399		386
400	=cut	387	=cut
401		388
402	sub rcv($@) {	389	sub rcv($@) {
403	my $port = shift;	390	my $port = shift;
404	my ($noderef, $portid) = split /#/, $port, 2;	391	my ($noderef, $portid) = split /#/, $port, 2;
405		392
406	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}	393	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}
407	or Carp::croak "$port: rcv can only be called on local ports, caught";	394	or Carp::croak "$port: rcv can only be called on local ports, caught";
408		395
409	if (@_ == 1) {	396	while (@_) {
		397	if (ref $_[0]) {
		398	if (my $self = $PORT_DATA{$portid}) {
		399	"AnyEvent::MP::Port" eq ref $self
		400	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
		401
		402	$self->[2] = shift;
		403	} else {
410	my $cb = shift;	404	my $cb = shift;
411	delete $PORT_DATA{$portid};
412	$PORT{$portid} = sub {	405	$PORT{$portid} = sub {
413	local $SELF = $port;	406	local $SELF = $port;
414	eval {	407	eval { &$cb }; _self_die if $@;
415	&$cb	408	};
416	and kil $port;
417	};	409	}
418	_self_die if $@;	410	} elsif (defined $_[0]) {
419	};
420	} else {
421	my $self = $PORT_DATA{$portid} \|\|= do {	411	my $self = $PORT_DATA{$portid} \|\|= do {
422	my $self = bless {	412	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
423	id => $port,
424	}, "AnyEvent::MP::Port";
425		413
426	$PORT{$portid} = sub {	414	$PORT{$portid} = sub {
427	local $SELF = $port;	415	local $SELF = $port;
428		416
429	eval {
430	for (@{ $self->{rc0}{$_[0]} }) {	417	if (my $cb = $self->[1]{$_[0]}) {
431	$_ && &{$_->[0]}	418	shift;
432	&& undef $_;	419	eval { &$cb }; _self_die if $@;
433	}	420	} else {
434
435	for (@{ $self->{rcv}{$_[0]} }) {
436	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
437	&& &{$_->[0]}	421	&{ $self->[0] };
438	&& undef $_;
439	}
440
441	for (@{ $self->{any} }) {
442	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
443	&& &{$_->[0]}
444	&& undef $_;
445	}	422	}
446	};	423	};
447	_self_die if $@;	424
		425	$self
448	};	426	};
449		427
450	$self
451	};
452
453	"AnyEvent::MP::Port" eq ref $self	428	"AnyEvent::MP::Port" eq ref $self
454	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	429	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
455		430
456	while (@_) {
457	my ($match, $cb) = splice @_, 0, 2;	431	my ($tag, $cb) = splice @_, 0, 2;
458		432
459	if (!ref $match) {	433	if (defined $cb) {
460	push @{ $self->{rc0}{$match} }, [$cb];	434	$self->[1]{$tag} = $cb;
461	} elsif (("ARRAY" eq ref $match && !ref $match->[0])) {
462	my ($type, @match) = @$match;
463	@match
464	? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match]
465	: push @{ $self->{rc0}{$match->[0]} }, [$cb];
466	} else {	435	} else {
467	push @{ $self->{any} }, [$cb, $match];	436	delete $self->[1]{$tag};
468	}	437	}
469	}	438	}
470	}	439	}
471		440
472	$port	441	$port
…		…
697	my $id = "$RUNIQ." . $ID++;	666	my $id = "$RUNIQ." . $ID++;
698		667
699	$_[0] =~ /::/	668	$_[0] =~ /::/
700	or Carp::croak "spawn init function must be a fully-qualified name, caught";	669	or Carp::croak "spawn init function must be a fully-qualified name, caught";
701		670
702	($NODE{$noderef} \|\| add_node $noderef)	671	snd_to_func $noderef, "AnyEvent::MP::_spawn" => $id, @_;
703	->send (["", "AnyEvent::MP::_spawn" => $id, @_]);
704		672
705	"$noderef#$id"	673	"$noderef#$id"
706	}	674	}
707		675
708	=back	676	=back
…		…
776	convenience functionality.	744	convenience functionality.
777		745
778	This means that AEMP requires a less tightly controlled environment at the	746	This means that AEMP requires a less tightly controlled environment at the
779	cost of longer node references and a slightly higher management overhead.	747	cost of longer node references and a slightly higher management overhead.
780		748
		749	=item * Erlang has a "remote ports are like local ports" philosophy, AEMP
		750	uses "local ports are like remote ports".
		751
		752	The failure modes for local ports are quite different (runtime errors
		753	only) then for remote ports - when a local port dies, you I<know> it dies,
		754	when a connection to another node dies, you know nothing about the other
		755	port.
		756
		757	Erlang pretends remote ports are as reliable as local ports, even when
		758	they are not.
		759
		760	AEMP encourages a "treat remote ports differently" philosophy, with local
		761	ports being the special case/exception, where transport errors cannot
		762	occur.
		763
781	=item * Erlang uses processes and a mailbox, AEMP does not queue.	764	=item * Erlang uses processes and a mailbox, AEMP does not queue.
782		765
783	Erlang uses processes that selctively receive messages, and therefore	766	Erlang uses processes that selectively receive messages, and therefore
784	needs a queue. AEMP is event based, queuing messages would serve no useful	767	needs a queue. AEMP is event based, queuing messages would serve no
785	purpose.	768	useful purpose. For the same reason the pattern-matching abilities of
		769	AnyEvent::MP are more limited, as there is little need to be able to
		770	filter messages without dequeing them.
786		771
787	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	772	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).
788		773
789	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	774	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
790		775
791	Sending messages in Erlang is synchronous and blocks the process. AEMP	776	Sending messages in Erlang is synchronous and blocks the process (and
792	sends are immediate, connection establishment is handled in the	777	so does not need a queue that can overflow). AEMP sends are immediate,
793	background.	778	connection establishment is handled in the background.
794		779
795	=item * Erlang can silently lose messages, AEMP cannot.	780	=item * Erlang suffers from silent message loss, AEMP does not.
796		781
797	Erlang makes few guarantees on messages delivery - messages can get lost	782	Erlang makes few guarantees on messages delivery - messages can get lost
798	without any of the processes realising it (i.e. you send messages a, b,	783	without any of the processes realising it (i.e. you send messages a, b,
799	and c, and the other side only receives messages a and c).	784	and c, and the other side only receives messages a and c).
800		785
…		…
812	eventually be killed - it cannot happen that a node detects a port as dead	797	eventually be killed - it cannot happen that a node detects a port as dead
813	and then later sends messages to it, finding it is still alive.	798	and then later sends messages to it, finding it is still alive.
814		799
815	=item * Erlang can send messages to the wrong port, AEMP does not.	800	=item * Erlang can send messages to the wrong port, AEMP does not.
816		801
817	In Erlang it is quite possible that a node that restarts reuses a process	802	In Erlang it is quite likely that a node that restarts reuses a process ID
818	ID known to other nodes for a completely different process, causing	803	known to other nodes for a completely different process, causing messages
819	messages destined for that process to end up in an unrelated process.	804	destined for that process to end up in an unrelated process.
820		805
821	AEMP never reuses port IDs, so old messages or old port IDs floating	806	AEMP never reuses port IDs, so old messages or old port IDs floating
822	around in the network will not be sent to an unrelated port.	807	around in the network will not be sent to an unrelated port.
823		808
824	=item * Erlang uses unprotected connections, AEMP uses secure	809	=item * Erlang uses unprotected connections, AEMP uses secure

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Comparing AnyEvent-MP/MP.pm (file contents): Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs. Revision 1.55 by root, Fri Aug 14 23:17:17 2009 UTC

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Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs.
Revision 1.55 by root, Fri Aug 14 23:17:17 2009 UTC