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

Comparing cvsroot/AnyEvent-MP/MP.pm (file contents):
Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs.
Revision 1.54 by root, Fri Aug 14 16:15:37 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
…		…
284	=item snd $port, type => @data	277	=item snd $port, type => @data
285		278
286	=item snd $port, @msg	279	=item snd $port, @msg
287		280
288	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
289	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.
290	stringifies a sa port ID (such as a port object :).
291		283
292	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
293	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
294	type etc.).	286	type etc.).
295		287
296	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
297	function: modifying any argument is not allowed and can cause many	289	function: modifying any argument is not allowed and can cause many
298	problems.	290	problems.
…		…
303	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
304	node, anything can be passed.	296	node, anything can be passed.
305		297
306	=item $local_port = port	298	=item $local_port = port
307		299
308	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
309	matching port ("full port") or a single-callback port ("miniport"),	301	no callbacks set and will throw an error when it receives messages.
310	depending on how C<rcv> callbacks are bound to the object.
311		302
312	=item $port = port { my @msg = @_; $finished }	303	=item $local_port = port { my @msg = @_ }
313		304
314	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
315	matching behind it, and returns its ID. Semantically the same as creating
316	a port and calling C<rcv $port, $callback> on it.	306	creating a port and calling C<rcv $port, $callback> on it.
317		307
318	The block will be called for every message received on the port. When the	308	The block will be called for every message received on the port, with the
319	callback returns a true value its job is considered "done" and the port	309	global variable C<$SELF> set to the port ID. Runtime errors will cause the
320	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.
321		312
322	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:
323	be passed to the callback.
324		314
325	If you need the local port id in the callback, this works nicely:	315	my $port = port {
326		316	my @msg = @_;
327	my $port; $port = port {	317	...
328	snd $otherport, reply => $port;	318	kil $SELF;
329	};	319	};
330		320
331	=cut	321	=cut
332		322
333	sub rcv($@);	323	sub rcv($@);
		324
		325	sub _kilme {
		326	die "received message on port without callback";
		327	}
334		328
335	sub port(;&) {	329	sub port(;&) {
336	my $id = "$UNIQ." . $ID++;	330	my $id = "$UNIQ." . $ID++;
337	my $port = "$NODE#$id";	331	my $port = "$NODE#$id";
338		332
339	if (@_) {	333	rcv $port, shift \|\| \&_kilme;
340	rcv $port, shift;
341	} else {
342	$PORT{$id} = sub { }; # nop
343	}
344		334
345	$port	335	$port
346	}	336	}
347		337
348	=item reg $port, $name
349
350	=item reg $name
351
352	Registers the given port (or C<$SELF><<< if missing) under the name
353	C<$name>. If the name already exists it is replaced.
354
355	A port can only be registered under one well known name.
356
357	A port automatically becomes unregistered when it is killed.
358
359	=cut
360
361	sub reg(@) {
362	my $port = @_ > 1 ? shift : $SELF \|\| Carp::croak 'reg: called with one argument only, but $SELF not set,';
363
364	$REG{$_[0]} = $port;
365	}
366
367	=item rcv $port, $callback->(@msg)	338	=item rcv $local_port, $callback->(@msg)
368		339
369	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
370	one if required).	341	remove the default callback: use C<sub { }> to disable it, or better
371		342	C<kil> the port when it is no longer needed.
372	=item rcv $port, tagstring => $callback->(@msg), ...
373
374	=item rcv $port, $smartmatch => $callback->(@msg), ...
375
376	=item rcv $port, [$smartmatch...] => $callback->(@msg), ...
377
378	Register callbacks to be called on matching messages on the given full
379	port (after converting it to one if required) and return the port.
380
381	The callback has to return a true value when its work is done, after
382	which is will be removed, or a false value in which case it will stay
383	registered.
384		343
385	The global C<$SELF> (exported by this module) contains C<$port> while	344	The global C<$SELF> (exported by this module) contains C<$port> while
386	executing the callback.	345	executing the callback. Runtime errors during callback execution will
		346	result in the port being C<kil>ed.
387		347
388	Runtime errors during callback execution will result in the port being	348	The default callback received all messages not matched by a more specific
389	C<kil>ed.	349	C<tag> match.
390		350
391	If the match is an array reference, then it will be matched against the	351	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
392	first elements of the message, otherwise only the first element is being
393	matched.
394		352
395	Any element in the match that is specified as C<_any_> (a function	353	Register (or replace) callbacks to be called on messages starting with the
396	exported by this module) matches any single element of the message.	354	given tag on the given port (and return the port), or unregister it (when
		355	C<$callback> is C<$undef> or missing). There can only be one callback
		356	registered for each tag.
397		357
398	While not required, it is highly recommended that the first matching	358	The original message will be passed to the callback, after the first
399	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
400	also the most efficient match (by far).	360	environment as the default callback (see above).
401		361
402	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.
403		363
404	my $port = rcv port,	364	my $port = rcv port,
405	msg1 => sub { ...; 0 },	365	msg1 => sub { ... },
406	msg2 => sub { ...; 0 },	366	msg2 => sub { ... },
407	;	367	;
408		368
409	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
410	in one go:	370	in one go:
411		371
412	snd $otherport, reply =>	372	snd $otherport, reply =>
413	rcv port,	373	rcv port,
414	msg1 => sub { ...; 0 },	374	msg1 => sub { ... },
415	...	375	...
416	;	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, $otherport;
		385	};
417		386
418	=cut	387	=cut
419		388
420	sub rcv($@) {	389	sub rcv($@) {
421	my $port = shift;	390	my $port = shift;
422	my ($noderef, $portid) = split /#/, $port, 2;	391	my ($noderef, $portid) = split /#/, $port, 2;
423		392
424	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}	393	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}
425	or Carp::croak "$port: rcv can only be called on local ports, caught";	394	or Carp::croak "$port: rcv can only be called on local ports, caught";
426		395
427	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 {
428	my $cb = shift;	404	my $cb = shift;
429	delete $PORT_DATA{$portid};
430	$PORT{$portid} = sub {	405	$PORT{$portid} = sub {
431	local $SELF = $port;	406	local $SELF = $port;
432	eval {	407	eval { &$cb }; _self_die if $@;
433	&$cb	408	};
434	and kil $port;
435	};	409	}
436	_self_die if $@;	410	} elsif (defined $_[0]) {
437	};
438	} else {
439	my $self = $PORT_DATA{$portid} \|\|= do {	411	my $self = $PORT_DATA{$portid} \|\|= do {
440	my $self = bless {	412	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
441	id => $port,
442	}, "AnyEvent::MP::Port";
443		413
444	$PORT{$portid} = sub {	414	$PORT{$portid} = sub {
445	local $SELF = $port;	415	local $SELF = $port;
446		416
447	eval {
448	for (@{ $self->{rc0}{$_[0]} }) {	417	if (my $cb = $self->[1]{$_[0]}) {
449	$_ && &{$_->[0]}	418	shift;
450	&& undef $_;	419	eval { &$cb }; _self_die if $@;
451	}	420	} else {
452
453	for (@{ $self->{rcv}{$_[0]} }) {
454	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
455	&& &{$_->[0]}	421	&{ $self->[0] };
456	&& undef $_;
457	}
458
459	for (@{ $self->{any} }) {
460	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
461	&& &{$_->[0]}
462	&& undef $_;
463	}	422	}
464	};	423	};
465	_self_die if $@;	424
		425	$self
466	};	426	};
467		427
468	$self
469	};
470
471	"AnyEvent::MP::Port" eq ref $self	428	"AnyEvent::MP::Port" eq ref $self
472	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	429	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
473		430
474	while (@_) {
475	my ($match, $cb) = splice @_, 0, 2;	431	my ($tag, $cb) = splice @_, 0, 2;
476		432
477	if (!ref $match) {	433	if (defined $cb) {
478	push @{ $self->{rc0}{$match} }, [$cb];	434	$self->[1]{$tag} = $cb;
479	} elsif (("ARRAY" eq ref $match && !ref $match->[0])) {
480	my ($type, @match) = @$match;
481	@match
482	? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match]
483	: push @{ $self->{rc0}{$match->[0]} }, [$cb];
484	} else {	435	} else {
485	push @{ $self->{any} }, [$cb, $match];	436	delete $self->[1]{$tag};
486	}	437	}
487	}	438	}
488	}	439	}
489		440
490	$port	441	$port
…		…
794	convenience functionality.	745	convenience functionality.
795		746
796	This means that AEMP requires a less tightly controlled environment at the	747	This means that AEMP requires a less tightly controlled environment at the
797	cost of longer node references and a slightly higher management overhead.	748	cost of longer node references and a slightly higher management overhead.
798		749
		750	=item * Erlang has a "remote ports are like local ports" philosophy, AEMP
		751	uses "local ports are like remote ports".
		752
		753	The failure modes for local ports are quite different (runtime errors
		754	only) then for remote ports - when a local port dies, you I<know> it dies,
		755	when a connection to another node dies, you know nothing about the other
		756	port.
		757
		758	Erlang pretends remote ports are as reliable as local ports, even when
		759	they are not.
		760
		761	AEMP encourages a "treat remote ports differently" philosophy, with local
		762	ports being the special case/exception, where transport errors cannot
		763	occur.
		764
799	=item * Erlang uses processes and a mailbox, AEMP does not queue.	765	=item * Erlang uses processes and a mailbox, AEMP does not queue.
800		766
801	Erlang uses processes that selctively receive messages, and therefore	767	Erlang uses processes that selectively receive messages, and therefore
802	needs a queue. AEMP is event based, queuing messages would serve no useful	768	needs a queue. AEMP is event based, queuing messages would serve no
803	purpose.	769	useful purpose. For the same reason the pattern-matching abilities of
		770	AnyEvent::MP are more limited, as there is little need to be able to
		771	filter messages without dequeing them.
804		772
805	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	773	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).
806		774
807	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	775	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
808		776
809	Sending messages in Erlang is synchronous and blocks the process. AEMP	777	Sending messages in Erlang is synchronous and blocks the process (and
810	sends are immediate, connection establishment is handled in the	778	so does not need a queue that can overflow). AEMP sends are immediate,
811	background.	779	connection establishment is handled in the background.
812		780
813	=item * Erlang can silently lose messages, AEMP cannot.	781	=item * Erlang suffers from silent message loss, AEMP does not.
814		782
815	Erlang makes few guarantees on messages delivery - messages can get lost	783	Erlang makes few guarantees on messages delivery - messages can get lost
816	without any of the processes realising it (i.e. you send messages a, b,	784	without any of the processes realising it (i.e. you send messages a, b,
817	and c, and the other side only receives messages a and c).	785	and c, and the other side only receives messages a and c).
818		786
…		…
830	eventually be killed - it cannot happen that a node detects a port as dead	798	eventually be killed - it cannot happen that a node detects a port as dead
831	and then later sends messages to it, finding it is still alive.	799	and then later sends messages to it, finding it is still alive.
832		800
833	=item * Erlang can send messages to the wrong port, AEMP does not.	801	=item * Erlang can send messages to the wrong port, AEMP does not.
834		802
835	In Erlang it is quite possible that a node that restarts reuses a process	803	In Erlang it is quite likely that a node that restarts reuses a process ID
836	ID known to other nodes for a completely different process, causing	804	known to other nodes for a completely different process, causing messages
837	messages destined for that process to end up in an unrelated process.	805	destined for that process to end up in an unrelated process.
838		806
839	AEMP never reuses port IDs, so old messages or old port IDs floating	807	AEMP never reuses port IDs, so old messages or old port IDs floating
840	around in the network will not be sent to an unrelated port.	808	around in the network will not be sent to an unrelated port.
841		809
842	=item * Erlang uses unprotected connections, AEMP uses secure	810	=item * Erlang uses unprotected connections, AEMP uses secure

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Comparing cvsroot/AnyEvent-MP/MP.pm (file contents): Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs. Revision 1.54 by root, Fri Aug 14 16:15:37 2009 UTC

Diff Legend

Comparing cvsroot/AnyEvent-MP/MP.pm (file contents):
Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs.
Revision 1.54 by root, Fri Aug 14 16:15:37 2009 UTC