[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 1.52 by root, Fri Aug 14 15:13:20 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 $somple_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
…		…
148	kil $SELF, die => $msg;	143	kil $SELF, die => $msg;
149	}	144	}
150		145
151	=item $thisnode = NODE / $NODE	146	=item $thisnode = NODE / $NODE
152		147
153	The C<NODE> function returns, and the C<$NODE> variable contains	148	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	149	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	150	C<initialise_node>.
156	identifiers become invalid.
157		151
158	=item $noderef = node_of $port	152	=item $noderef = node_of $port
159		153
160	Extracts and returns the noderef from a portid or a noderef.	154	Extracts and returns the noderef from a port ID or a noderef.
161		155
162	=item initialise_node $noderef, $seednode, $seednode...	156	=item initialise_node $noderef, $seednode, $seednode...
163		157
164	=item initialise_node "slave/", $master, $master...	158	=item initialise_node "slave/", $master, $master...
165		159
…		…
168	it should know the noderefs of some other nodes in the network.	162	it should know the noderefs of some other nodes in the network.
169		163
170	This function initialises a node - it must be called exactly once (or	164	This function initialises a node - it must be called exactly once (or
171	never) before calling other AnyEvent::MP functions.	165	never) before calling other AnyEvent::MP functions.
172		166
173	All arguments are noderefs, which can be either resolved or unresolved.	167	All arguments (optionally except for the first) are noderefs, which can be
		168	either resolved or unresolved.
		169
		170	The first argument will be looked up in the configuration database first
		171	(if it is C<undef> then the current nodename will be used instead) to find
		172	the relevant configuration profile (see L<aemp>). If none is found then
		173	the default configuration is used. The configuration supplies additional
		174	seed/master nodes and can override the actual noderef.
174		175
175	There are two types of networked nodes, public nodes and slave nodes:	176	There are two types of networked nodes, public nodes and slave nodes:
176		177
177	=over 4	178	=over 4
178		179
179	=item public nodes	180	=item public nodes
180		181
181	For public nodes, C<$noderef> must either be a (possibly unresolved)	182	For public nodes, C<$noderef> (supplied either directly to
182	noderef, in which case it will be resolved, or C<undef> (or missing), in	183	C<initialise_node> or indirectly via a profile or the nodename) must be a
183	which case the noderef will be guessed.	184	noderef (possibly unresolved, in which case it will be resolved).
184		185
185	Afterwards, the node will bind itself on all endpoints and try to connect	186	After resolving, the node will bind itself on all endpoints and try to
186	to all additional C<$seednodes> that are specified. Seednodes are optional	187	connect to all additional C<$seednodes> that are specified. Seednodes are
187	and can be used to quickly bootstrap the node into an existing network.	188	optional and can be used to quickly bootstrap the node into an existing
		189	network.
188		190
189	=item slave nodes	191	=item slave nodes
190		192
191	When the C<$noderef> is the special string C<slave/>, then the node will	193	When the C<$noderef> (either as given or overriden by the config file)
		194	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	195	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.	196	their traffic to the master node that they attach to.
194		197
195	At least one additional noderef is required: The node will try to connect	198	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	199	directly or because it is part of the configuration profile): The node
197	successfully connect to.	200	will try to connect to all of them and will become a slave attached to the
		201	first node it can successfully connect to.
198		202
199	=back	203	=back
200		204
201	This function will block until all nodes have been resolved and, for slave	205	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	206	nodes, until it has successfully established a connection to a master
203	server.	207	server.
204		208
205	Example: become a public node listening on the default node.	209	Example: become a public node listening on the guessed noderef, or the one
		210	specified via C<aemp> for the current node. This should be the most common
		211	form of invocation for "daemon"-type nodes.
206		212
207	initialise_node;	213	initialise_node;
		214
		215	Example: become a slave node to any of the the seednodes specified via
		216	C<aemp>. This form is often used for commandline clients.
		217
		218	initialise_node "slave/";
		219
		220	Example: become a slave node to any of the specified master servers. This
		221	form is also often used for commandline clients.
		222
		223	initialise_node "slave/", "master1", "192.168.13.17", "mp.example.net";
208		224
209	Example: become a public node, and try to contact some well-known master	225	Example: become a public node, and try to contact some well-known master
210	servers to become part of the network.	226	servers to become part of the network.
211		227
212	initialise_node undef, "master1", "master2";	228	initialise_node undef, "master1", "master2";
…		…
215		231
216	initialise_node 4041;	232	initialise_node 4041;
217		233
218	Example: become a public node, only visible on localhost port 4044.	234	Example: become a public node, only visible on localhost port 4044.
219		235
220	initialise_node "locahost:4044";	236	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		237
226	=item $cv = resolve_node $noderef	238	=item $cv = resolve_node $noderef
227		239
228	Takes an unresolved node reference that may contain hostnames and	240	Takes an unresolved node reference that may contain hostnames and
229	abbreviated IDs, resolves all of them and returns a resolved node	241	abbreviated IDs, resolves all of them and returns a resolved node
…		…
266	=item snd $port, type => @data	278	=item snd $port, type => @data
267		279
268	=item snd $port, @msg	280	=item snd $port, @msg
269		281
270	Send the given message to the given port ID, which can identify either	282	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	283	a local or a remote port, and must be a port ID.
272	stringifies a sa port ID (such as a port object :).
273		284
274	While the message can be about anything, it is highly recommended to use a	285	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	286	string as first element (a port ID, or some word that indicates a request
276	type etc.).	287	type etc.).
277		288
278	The message data effectively becomes read-only after a call to this	289	The message data effectively becomes read-only after a call to this
279	function: modifying any argument is not allowed and can cause many	290	function: modifying any argument is not allowed and can cause many
280	problems.	291	problems.
…		…
285	that Storable can serialise and deserialise is allowed, and for the local	296	that Storable can serialise and deserialise is allowed, and for the local
286	node, anything can be passed.	297	node, anything can be passed.
287		298
288	=item $local_port = port	299	=item $local_port = port
289		300
290	Create a new local port object that can be used either as a pattern	301	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"),	302	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		303
294	=item $port = port { my @msg = @_; $finished }	304	=item $local_port = port { my @msg = @_ }
295		305
296	Creates a "miniport", that is, a very lightweight port without any pattern	306	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.	307	creating a port and calling C<rcv $port, $callback> on it.
299		308
300	The block will be called for every message received on the port. When the	309	The block will be called for every message received on the port, with the
301	callback returns a true value its job is considered "done" and the port	310	global variable C<$SELF> set to the port ID. Runtime errors will cause the
302	will be destroyed. Otherwise it will stay alive.	311	port to be C<kil>ed. The message will be passed as-is, no extra argument
		312	(i.e. no port ID) will be passed to the callback.
303		313
304	The message will be passed as-is, no extra argument (i.e. no port id) will	314	If you want to stop/destroy the port, simply C<kil> it:
305	be passed to the callback.
306		315
307	If you need the local port id in the callback, this works nicely:	316	my $port = port {
308		317	my @msg = @_;
309	my $port; $port = port {	318	...
310	snd $otherport, reply => $port;	319	kil $SELF;
311	};	320	};
312		321
313	=cut	322	=cut
314		323
315	sub rcv($@);	324	sub rcv($@);
		325
		326	sub _kilme {
		327	die "received message on port without callback";
		328	}
316		329
317	sub port(;&) {	330	sub port(;&) {
318	my $id = "$UNIQ." . $ID++;	331	my $id = "$UNIQ." . $ID++;
319	my $port = "$NODE#$id";	332	my $port = "$NODE#$id";
320		333
321	if (@_) {	334	rcv $port, shift \|\| \&_kilme;
322	rcv $port, shift;
323	} else {
324	$PORT{$id} = sub { }; # nop
325	}
326		335
327	$port	336	$port
328	}	337	}
329		338
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)	339	=item rcv $local_port, $callback->(@msg)
350		340
351	Replaces the callback on the specified miniport (after converting it to	341	Replaces the default callback on the specified port. There is no way to
352	one if required).	342	remove the default callback: use C<sub { }> to disable it, or better
353		343	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...] => $callback->(@msg), ...
359
360	Register callbacks to be called on matching messages on the given full
361	port (after converting it to one if required) and return the port.
362
363	The callback has to return a true value when its work is done, after
364	which is will be removed, or a false value in which case it will stay
365	registered.
366		344
367	The global C<$SELF> (exported by this module) contains C<$port> while	345	The global C<$SELF> (exported by this module) contains C<$port> while
368	executing the callback.	346	executing the callback. Runtime errors during callback execution will
		347	result in the port being C<kil>ed.
369		348
370	Runtime errors during callback execution will result in the port being	349	The default callback received all messages not matched by a more specific
371	C<kil>ed.	350	C<tag> match.
372		351
373	If the match is an array reference, then it will be matched against the	352	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
374	first elements of the message, otherwise only the first element is being
375	matched.
376		353
377	Any element in the match that is specified as C<_any_> (a function	354	Register callbacks to be called on messages starting with the given tag on
378	exported by this module) matches any single element of the message.	355	the given port (and return the port), or unregister it (when C<$callback>
		356	is C<$undef>).
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 $otherport, reply =>
395	rcv port,	373	rcv port,
396	msg1 => sub { ...; 0 },	374	msg1 => sub { ... },
397	...	375	...
398	;	376	;
399		377
400	=cut	378	=cut
401		379
…		…
404	my ($noderef, $portid) = split /#/, $port, 2;	382	my ($noderef, $portid) = split /#/, $port, 2;
405		383
406	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}	384	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}
407	or Carp::croak "$port: rcv can only be called on local ports, caught";	385	or Carp::croak "$port: rcv can only be called on local ports, caught";
408		386
409	if (@_ == 1) {	387	while (@_) {
		388	if (ref $_[0]) {
		389	if (my $self = $PORT_DATA{$portid}) {
		390	"AnyEvent::MP::Port" eq ref $self
		391	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
		392
		393	$self->[2] = shift;
		394	} else {
410	my $cb = shift;	395	my $cb = shift;
411	delete $PORT_DATA{$portid};
412	$PORT{$portid} = sub {	396	$PORT{$portid} = sub {
413	local $SELF = $port;	397	local $SELF = $port;
414	eval {	398	eval { &$cb }; _self_die if $@;
415	&$cb	399	};
416	and kil $port;
417	};	400	}
418	_self_die if $@;	401	} elsif (defined $_[0]) {
419	};
420	} else {
421	my $self = $PORT_DATA{$portid} \|\|= do {	402	my $self = $PORT_DATA{$portid} \|\|= do {
422	my $self = bless {	403	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
423	id => $port,
424	}, "AnyEvent::MP::Port";
425		404
426	$PORT{$portid} = sub {	405	$PORT{$portid} = sub {
427	local $SELF = $port;	406	local $SELF = $port;
428		407
429	eval {
430	for (@{ $self->{rc0}{$_[0]} }) {	408	if (my $cb = $self->[1]{$_[0]}) {
431	$_ && &{$_->[0]}	409	shift;
432	&& undef $_;	410	eval { &$cb }; _self_die if $@;
433	}	411	} else {
434
435	for (@{ $self->{rcv}{$_[0]} }) {
436	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
437	&& &{$_->[0]}	412	&{ $self->[0] };
438	&& undef $_;
439	}
440
441	for (@{ $self->{any} }) {
442	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
443	&& &{$_->[0]}
444	&& undef $_;
445	}	413	}
446	};	414	};
447	_self_die if $@;	415
		416	$self
448	};	417	};
449		418
450	$self
451	};
452
453	"AnyEvent::MP::Port" eq ref $self	419	"AnyEvent::MP::Port" eq ref $self
454	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	420	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
455		421
456	while (@_) {
457	my ($match, $cb) = splice @_, 0, 2;	422	my ($tag, $cb) = splice @_, 0, 2;
458		423
459	if (!ref $match) {	424	if (defined $cb) {
460	push @{ $self->{rc0}{$match} }, [$cb];	425	$self->[1]{$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 {	426	} else {
467	push @{ $self->{any} }, [$cb, $match];	427	delete $self->[1]{$tag};
468	}	428	}
469	}	429	}
470	}	430	}
471		431
472	$port	432	$port
…		…
776	convenience functionality.	736	convenience functionality.
777		737
778	This means that AEMP requires a less tightly controlled environment at the	738	This means that AEMP requires a less tightly controlled environment at the
779	cost of longer node references and a slightly higher management overhead.	739	cost of longer node references and a slightly higher management overhead.
780		740
		741	=item Erlang has a "remote ports are like local ports" philosophy, AEMP
		742	uses "local ports are like remote ports".
		743
		744	The failure modes for local ports are quite different (runtime errors
		745	only) then for remote ports - when a local port dies, you I<know> it dies,
		746	when a connection to another node dies, you know nothing about the other
		747	port.
		748
		749	Erlang pretends remote ports are as reliable as local ports, even when
		750	they are not.
		751
		752	AEMP encourages a "treat remote ports differently" philosophy, with local
		753	ports being the special case/exception, where transport errors cannot
		754	occur.
		755
781	=item * Erlang uses processes and a mailbox, AEMP does not queue.	756	=item * Erlang uses processes and a mailbox, AEMP does not queue.
782		757
783	Erlang uses processes that selctively receive messages, and therefore	758	Erlang uses processes that selectively receive messages, and therefore
784	needs a queue. AEMP is event based, queuing messages would serve no useful	759	needs a queue. AEMP is event based, queuing messages would serve no
785	purpose.	760	useful purpose. For the same reason the pattern-matching abilities of
		761	AnyEvent::MP are more limited, as there is little need to be able to
		762	filter messages without dequeing them.
786		763
787	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	764	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).
788		765
789	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	766	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
790		767
791	Sending messages in Erlang is synchronous and blocks the process. AEMP	768	Sending messages in Erlang is synchronous and blocks the process (and
792	sends are immediate, connection establishment is handled in the	769	so does not need a queue that can overflow). AEMP sends are immediate,
793	background.	770	connection establishment is handled in the background.
794		771
795	=item * Erlang can silently lose messages, AEMP cannot.	772	=item * Erlang suffers from silent message loss, AEMP does not.
796		773
797	Erlang makes few guarantees on messages delivery - messages can get lost	774	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,	775	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).	776	and c, and the other side only receives messages a and c).
800		777
…		…
812	eventually be killed - it cannot happen that a node detects a port as dead	789	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.	790	and then later sends messages to it, finding it is still alive.
814		791
815	=item * Erlang can send messages to the wrong port, AEMP does not.	792	=item * Erlang can send messages to the wrong port, AEMP does not.
816		793
817	In Erlang it is quite possible that a node that restarts reuses a process	794	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	795	known to other nodes for a completely different process, causing messages
819	messages destined for that process to end up in an unrelated process.	796	destined for that process to end up in an unrelated process.
820		797
821	AEMP never reuses port IDs, so old messages or old port IDs floating	798	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.	799	around in the network will not be sent to an unrelated port.
823		800
824	=item * Erlang uses unprotected connections, AEMP uses secure	801	=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 1.52 by root, Fri Aug 14 15:13:20 2009 UTC

Diff Legend

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs.
Revision 1.52 by root, Fri Aug 14 15:13:20 2009 UTC