… | |
… | |
35 | # destroy a port again |
35 | # destroy a port again |
36 | kil $port; # "normal" kill |
36 | kil $port; # "normal" kill |
37 | kil $port, my_error => "everything is broken"; # error kill |
37 | kil $port, my_error => "everything is broken"; # error kill |
38 | |
38 | |
39 | # monitoring |
39 | # monitoring |
40 | mon $localport, $cb->(@msg) # callback is invoked on death |
40 | mon $port, $cb->(@msg) # callback is invoked on death |
41 | mon $localport, $otherport # kill otherport on abnormal death |
41 | mon $port, $localport # kill localport on abnormal death |
42 | mon $localport, $otherport, @msg # send message on death |
42 | mon $port, $localport, @msg # send message on death |
43 | |
43 | |
44 | # temporarily execute code in port context |
44 | # temporarily execute code in port context |
45 | peval $port, sub { die "kill the port!" }; |
45 | peval $port, sub { die "kill the port!" }; |
46 | |
46 | |
47 | # execute callbacks in $SELF port context |
47 | # execute callbacks in $SELF port context |
… | |
… | |
185 | use common::sense; |
185 | use common::sense; |
186 | |
186 | |
187 | use Carp (); |
187 | use Carp (); |
188 | |
188 | |
189 | use AE (); |
189 | use AE (); |
|
|
190 | use Guard (); |
190 | |
191 | |
191 | use base "Exporter"; |
192 | use base "Exporter"; |
192 | |
193 | |
193 | our $VERSION = $AnyEvent::MP::Config::VERSION; |
194 | our $VERSION = $AnyEvent::MP::Config::VERSION; |
194 | |
195 | |
195 | our @EXPORT = qw( |
196 | our @EXPORT = qw( |
196 | NODE $NODE *SELF node_of after |
197 | NODE $NODE *SELF node_of after |
197 | configure |
198 | configure |
198 | snd rcv mon mon_guard kil psub peval spawn cal |
199 | snd rcv mon mon_guard kil psub peval spawn cal |
199 | port |
200 | port |
|
|
201 | db_set db_del db_reg |
|
|
202 | db_mon db_family db_keys db_values |
200 | ); |
203 | ); |
201 | |
204 | |
202 | our $SELF; |
205 | our $SELF; |
203 | |
206 | |
204 | sub _self_die() { |
207 | sub _self_die() { |
… | |
… | |
228 | |
231 | |
229 | This function configures a node - it must be called exactly once (or |
232 | This function configures a node - it must be called exactly once (or |
230 | never) before calling other AnyEvent::MP functions. |
233 | never) before calling other AnyEvent::MP functions. |
231 | |
234 | |
232 | The key/value pairs are basically the same ones as documented for the |
235 | The key/value pairs are basically the same ones as documented for the |
233 | F<aemp> command line utility (sans the set/del prefix), with two additions: |
236 | F<aemp> command line utility (sans the set/del prefix), with these additions: |
234 | |
237 | |
235 | =over 4 |
238 | =over 4 |
236 | |
239 | |
237 | =item norc => $boolean (default false) |
240 | =item norc => $boolean (default false) |
238 | |
241 | |
… | |
… | |
243 | =item force => $boolean (default false) |
246 | =item force => $boolean (default false) |
244 | |
247 | |
245 | IF true, then the values specified in the C<configure> will take |
248 | IF true, then the values specified in the C<configure> will take |
246 | precedence over any values configured via the rc file. The default is for |
249 | precedence over any values configured via the rc file. The default is for |
247 | the rc file to override any options specified in the program. |
250 | the rc file to override any options specified in the program. |
|
|
251 | |
|
|
252 | =item secure => $pass->(@msg) |
|
|
253 | |
|
|
254 | In addition to specifying a boolean, you can specify a code reference that |
|
|
255 | is called for every code execution attempt - the execution request is |
|
|
256 | granted iff the callback returns a true value. |
|
|
257 | |
|
|
258 | Most of the time the callback should look only at |
|
|
259 | C<$AnyEvent::MP::Kernel::SRCNODE> to make a decision, and not at the |
|
|
260 | actual message (which can be about anything, and is mostly provided for |
|
|
261 | diagnostic purposes). |
|
|
262 | |
|
|
263 | See F<semp setsecure> for more info. |
248 | |
264 | |
249 | =back |
265 | =back |
250 | |
266 | |
251 | =over 4 |
267 | =over 4 |
252 | |
268 | |
… | |
… | |
269 | and the values specified directly via C<configure> have lowest priority, |
285 | and the values specified directly via C<configure> have lowest priority, |
270 | and can only be used to specify defaults. |
286 | and can only be used to specify defaults. |
271 | |
287 | |
272 | If the profile specifies a node ID, then this will become the node ID of |
288 | If the profile specifies a node ID, then this will become the node ID of |
273 | this process. If not, then the profile name will be used as node ID, with |
289 | this process. If not, then the profile name will be used as node ID, with |
274 | a slash (C</>) attached. |
290 | a unique randoms tring (C</%u>) appended. |
275 | |
291 | |
276 | If the node ID (or profile name) ends with a slash (C</>), then a random |
292 | The node ID can contain some C<%> sequences that are expanded: C<%n> |
277 | string is appended to make it unique. |
293 | is expanded to the local nodename, C<%u> is replaced by a random |
|
|
294 | strign to make the node unique. For example, the F<aemp> commandline |
|
|
295 | utility uses C<aemp/%n/%u> as nodename, which might expand to |
|
|
296 | C<aemp/cerebro/ZQDGSIkRhEZQDGSIkRhE>. |
278 | |
297 | |
279 | =item step 2, bind listener sockets |
298 | =item step 2, bind listener sockets |
280 | |
299 | |
281 | The next step is to look up the binds in the profile, followed by binding |
300 | The next step is to look up the binds in the profile, followed by binding |
282 | aemp protocol listeners on all binds specified (it is possible and valid |
301 | aemp protocol listeners on all binds specified (it is possible and valid |
… | |
… | |
299 | Example: become a distributed node using the local node name as profile. |
318 | Example: become a distributed node using the local node name as profile. |
300 | This should be the most common form of invocation for "daemon"-type nodes. |
319 | This should be the most common form of invocation for "daemon"-type nodes. |
301 | |
320 | |
302 | configure |
321 | configure |
303 | |
322 | |
304 | Example: become an anonymous node. This form is often used for commandline |
323 | Example: become a semi-anonymous node. This form is often used for |
305 | clients. |
324 | commandline clients. |
306 | |
325 | |
307 | configure nodeid => "anon/"; |
326 | configure nodeid => "myscript/%n/%u"; |
308 | |
327 | |
309 | Example: configure a node using a profile called seed, which is suitable |
328 | Example: configure a node using a profile called seed, which is suitable |
310 | for a seed node as it binds on all local addresses on a fixed port (4040, |
329 | for a seed node as it binds on all local addresses on a fixed port (4040, |
311 | customary for aemp). |
330 | customary for aemp). |
312 | |
331 | |
… | |
… | |
384 | |
403 | |
385 | =cut |
404 | =cut |
386 | |
405 | |
387 | sub rcv($@); |
406 | sub rcv($@); |
388 | |
407 | |
389 | sub _kilme { |
408 | my $KILME = sub { |
390 | die "received message on port without callback"; |
409 | (my $tag = substr $_[0], 0, 30) =~ s/([\x20-\x7e])/./g; |
391 | } |
410 | kil $SELF, unhandled_message => "no callback found for message '$tag'"; |
|
|
411 | }; |
392 | |
412 | |
393 | sub port(;&) { |
413 | sub port(;&) { |
394 | my $id = $UNIQ . ++$ID; |
414 | my $id = $UNIQ . ++$ID; |
395 | my $port = "$NODE#$id"; |
415 | my $port = "$NODE#$id"; |
396 | |
416 | |
397 | rcv $port, shift || \&_kilme; |
417 | rcv $port, shift || $KILME; |
398 | |
418 | |
399 | $port |
419 | $port |
400 | } |
420 | } |
401 | |
421 | |
402 | =item rcv $local_port, $callback->(@msg) |
422 | =item rcv $local_port, $callback->(@msg) |
… | |
… | |
407 | |
427 | |
408 | The global C<$SELF> (exported by this module) contains C<$port> while |
428 | The global C<$SELF> (exported by this module) contains C<$port> while |
409 | executing the callback. Runtime errors during callback execution will |
429 | executing the callback. Runtime errors during callback execution will |
410 | result in the port being C<kil>ed. |
430 | result in the port being C<kil>ed. |
411 | |
431 | |
412 | The default callback received all messages not matched by a more specific |
432 | The default callback receives all messages not matched by a more specific |
413 | C<tag> match. |
433 | C<tag> match. |
414 | |
434 | |
415 | =item rcv $local_port, tag => $callback->(@msg_without_tag), ... |
435 | =item rcv $local_port, tag => $callback->(@msg_without_tag), ... |
416 | |
436 | |
417 | Register (or replace) callbacks to be called on messages starting with the |
437 | Register (or replace) callbacks to be called on messages starting with the |
… | |
… | |
672 | } |
692 | } |
673 | |
693 | |
674 | $node->monitor ($port, $cb); |
694 | $node->monitor ($port, $cb); |
675 | |
695 | |
676 | defined wantarray |
696 | defined wantarray |
677 | and ($cb += 0, AnyEvent::Util::guard { $node->unmonitor ($port, $cb) }) |
697 | and ($cb += 0, Guard::guard { $node->unmonitor ($port, $cb) }) |
678 | } |
698 | } |
679 | |
699 | |
680 | =item $guard = mon_guard $port, $ref, $ref... |
700 | =item $guard = mon_guard $port, $ref, $ref... |
681 | |
701 | |
682 | Monitors the given C<$port> and keeps the passed references. When the port |
702 | Monitors the given C<$port> and keeps the passed references. When the port |
… | |
… | |
718 | will be reported as reason C<< die => $@ >>. |
738 | will be reported as reason C<< die => $@ >>. |
719 | |
739 | |
720 | Transport/communication errors are reported as C<< transport_error => |
740 | Transport/communication errors are reported as C<< transport_error => |
721 | $message >>. |
741 | $message >>. |
722 | |
742 | |
723 | =cut |
743 | Common idioms: |
|
|
744 | |
|
|
745 | # silently remove yourself, do not kill linked ports |
|
|
746 | kil $SELF; |
|
|
747 | |
|
|
748 | # report a failure in some detail |
|
|
749 | kil $SELF, failure_mode_1 => "it failed with too high temperature"; |
|
|
750 | |
|
|
751 | # do not waste much time with killing, just die when something goes wrong |
|
|
752 | open my $fh, "<file" |
|
|
753 | or die "file: $!"; |
724 | |
754 | |
725 | =item $port = spawn $node, $initfunc[, @initdata] |
755 | =item $port = spawn $node, $initfunc[, @initdata] |
726 | |
756 | |
727 | Creates a port on the node C<$node> (which can also be a port ID, in which |
757 | Creates a port on the node C<$node> (which can also be a port ID, in which |
728 | case it's the node where that port resides). |
758 | case it's the node where that port resides). |
… | |
… | |
820 | ref $action[0] |
850 | ref $action[0] |
821 | ? $action[0]() |
851 | ? $action[0]() |
822 | : snd @action; |
852 | : snd @action; |
823 | }; |
853 | }; |
824 | } |
854 | } |
|
|
855 | |
|
|
856 | #=item $cb2 = timeout $seconds, $cb[, @args] |
825 | |
857 | |
826 | =item cal $port, @msg, $callback[, $timeout] |
858 | =item cal $port, @msg, $callback[, $timeout] |
827 | |
859 | |
828 | A simple form of RPC - sends a message to the given C<$port> with the |
860 | A simple form of RPC - sends a message to the given C<$port> with the |
829 | given contents (C<@msg>), but adds a reply port to the message. |
861 | given contents (C<@msg>), but adds a reply port to the message. |
… | |
… | |
875 | $port |
907 | $port |
876 | } |
908 | } |
877 | |
909 | |
878 | =back |
910 | =back |
879 | |
911 | |
|
|
912 | =head1 DISTRIBUTED DATABASE |
|
|
913 | |
|
|
914 | AnyEvent::MP comes with a simple distributed database. The database will |
|
|
915 | be mirrored asynchronously on all global nodes. Other nodes bind to one |
|
|
916 | of the global nodes for their needs. Every node has a "local database" |
|
|
917 | which contains all the values that are set locally. All local databases |
|
|
918 | are merged together to form the global database, which can be queried. |
|
|
919 | |
|
|
920 | The database structure is that of a two-level hash - the database hash |
|
|
921 | contains hashes which contain values, similarly to a perl hash of hashes, |
|
|
922 | i.e.: |
|
|
923 | |
|
|
924 | $DATABASE{$family}{$subkey} = $value |
|
|
925 | |
|
|
926 | The top level hash key is called "family", and the second-level hash key |
|
|
927 | is called "subkey" or simply "key". |
|
|
928 | |
|
|
929 | The family must be alphanumeric, i.e. start with a letter and consist |
|
|
930 | of letters, digits, underscores and colons (C<[A-Za-z][A-Za-z0-9_:]*>, |
|
|
931 | pretty much like Perl module names. |
|
|
932 | |
|
|
933 | As the family namespace is global, it is recommended to prefix family names |
|
|
934 | with the name of the application or module using it. |
|
|
935 | |
|
|
936 | The subkeys must be non-empty strings, with no further restrictions. |
|
|
937 | |
|
|
938 | The values should preferably be strings, but other perl scalars should |
|
|
939 | work as well (such as C<undef>, arrays and hashes). |
|
|
940 | |
|
|
941 | Every database entry is owned by one node - adding the same family/subkey |
|
|
942 | combination on multiple nodes will not cause discomfort for AnyEvent::MP, |
|
|
943 | but the result might be nondeterministic, i.e. the key might have |
|
|
944 | different values on different nodes. |
|
|
945 | |
|
|
946 | Different subkeys in the same family can be owned by different nodes |
|
|
947 | without problems, and in fact, this is the common method to create worker |
|
|
948 | pools. For example, a worker port for image scaling might do this: |
|
|
949 | |
|
|
950 | db_set my_image_scalers => $port; |
|
|
951 | |
|
|
952 | And clients looking for an image scaler will want to get the |
|
|
953 | C<my_image_scalers> keys from time to time: |
|
|
954 | |
|
|
955 | db_keys my_image_scalers => sub { |
|
|
956 | @ports = @{ $_[0] }; |
|
|
957 | }; |
|
|
958 | |
|
|
959 | Or better yet, they want to monitor the database family, so they always |
|
|
960 | have a reasonable up-to-date copy: |
|
|
961 | |
|
|
962 | db_mon my_image_scalers => sub { |
|
|
963 | @ports = keys %{ $_[0] }; |
|
|
964 | }; |
|
|
965 | |
|
|
966 | In general, you can set or delete single subkeys, but query and monitor |
|
|
967 | whole families only. |
|
|
968 | |
|
|
969 | If you feel the need to monitor or query a single subkey, try giving it |
|
|
970 | it's own family. |
|
|
971 | |
|
|
972 | =over |
|
|
973 | |
|
|
974 | =item $guard = db_set $family => $subkey [=> $value] |
|
|
975 | |
|
|
976 | Sets (or replaces) a key to the database - if C<$value> is omitted, |
|
|
977 | C<undef> is used instead. |
|
|
978 | |
|
|
979 | When called in non-void context, C<db_set> returns a guard that |
|
|
980 | automatically calls C<db_del> when it is destroyed. |
|
|
981 | |
|
|
982 | =item db_del $family => $subkey... |
|
|
983 | |
|
|
984 | Deletes one or more subkeys from the database family. |
|
|
985 | |
|
|
986 | =item $guard = db_reg $family => $port => $value |
|
|
987 | |
|
|
988 | =item $guard = db_reg $family => $port |
|
|
989 | |
|
|
990 | =item $guard = db_reg $family |
|
|
991 | |
|
|
992 | Registers a port in the given family and optionally returns a guard to |
|
|
993 | remove it. |
|
|
994 | |
|
|
995 | This function basically does the same as: |
|
|
996 | |
|
|
997 | db_set $family => $port => $value |
|
|
998 | |
|
|
999 | Except that the port is monitored and automatically removed from the |
|
|
1000 | database family when it is kil'ed. |
|
|
1001 | |
|
|
1002 | If C<$value> is missing, C<undef> is used. If C<$port> is missing, then |
|
|
1003 | C<$SELF> is used. |
|
|
1004 | |
|
|
1005 | This function is most useful to register a port in some port group (which |
|
|
1006 | is just another name for a database family), and have it removed when the |
|
|
1007 | port is gone. This works best when the port is a local port. |
|
|
1008 | |
|
|
1009 | =cut |
|
|
1010 | |
|
|
1011 | sub db_reg($$;$) { |
|
|
1012 | my $family = shift; |
|
|
1013 | my $port = @_ ? shift : $SELF; |
|
|
1014 | |
|
|
1015 | my $clr = sub { db_del $family => $port }; |
|
|
1016 | mon $port, $clr; |
|
|
1017 | |
|
|
1018 | db_set $family => $port => $_[0]; |
|
|
1019 | |
|
|
1020 | defined wantarray |
|
|
1021 | and &Guard::guard ($clr) |
|
|
1022 | } |
|
|
1023 | |
|
|
1024 | =item db_family $family => $cb->(\%familyhash) |
|
|
1025 | |
|
|
1026 | Queries the named database C<$family> and call the callback with the |
|
|
1027 | family represented as a hash. You can keep and freely modify the hash. |
|
|
1028 | |
|
|
1029 | =item db_keys $family => $cb->(\@keys) |
|
|
1030 | |
|
|
1031 | Same as C<db_family>, except it only queries the family I<subkeys> and passes |
|
|
1032 | them as array reference to the callback. |
|
|
1033 | |
|
|
1034 | =item db_values $family => $cb->(\@values) |
|
|
1035 | |
|
|
1036 | Same as C<db_family>, except it only queries the family I<values> and passes them |
|
|
1037 | as array reference to the callback. |
|
|
1038 | |
|
|
1039 | =item $guard = db_mon $family => $cb->($familyhash, \@added, \@changed, \@deleted) |
|
|
1040 | |
|
|
1041 | Creates a monitor on the given database family. Each time a key is set |
|
|
1042 | or or is deleted the callback is called with a hash containing the |
|
|
1043 | database family and three lists of added, changed and deleted subkeys, |
|
|
1044 | respectively. If no keys have changed then the array reference might be |
|
|
1045 | C<undef> or even missing. |
|
|
1046 | |
|
|
1047 | If not called in void context, a guard object is returned that, when |
|
|
1048 | destroyed, stops the monitor. |
|
|
1049 | |
|
|
1050 | The family hash reference and the key arrays belong to AnyEvent::MP and |
|
|
1051 | B<must not be modified or stored> by the callback. When in doubt, make a |
|
|
1052 | copy. |
|
|
1053 | |
|
|
1054 | As soon as possible after the monitoring starts, the callback will be |
|
|
1055 | called with the intiial contents of the family, even if it is empty, |
|
|
1056 | i.e. there will always be a timely call to the callback with the current |
|
|
1057 | contents. |
|
|
1058 | |
|
|
1059 | It is possible that the callback is called with a change event even though |
|
|
1060 | the subkey is already present and the value has not changed. |
|
|
1061 | |
|
|
1062 | The monitoring stops when the guard object is destroyed. |
|
|
1063 | |
|
|
1064 | Example: on every change to the family "mygroup", print out all keys. |
|
|
1065 | |
|
|
1066 | my $guard = db_mon mygroup => sub { |
|
|
1067 | my ($family, $a, $c, $d) = @_; |
|
|
1068 | print "mygroup members: ", (join " ", keys %$family), "\n"; |
|
|
1069 | }; |
|
|
1070 | |
|
|
1071 | Exmaple: wait until the family "My::Module::workers" is non-empty. |
|
|
1072 | |
|
|
1073 | my $guard; $guard = db_mon My::Module::workers => sub { |
|
|
1074 | my ($family, $a, $c, $d) = @_; |
|
|
1075 | return unless %$family; |
|
|
1076 | undef $guard; |
|
|
1077 | print "My::Module::workers now nonempty\n"; |
|
|
1078 | }; |
|
|
1079 | |
|
|
1080 | Example: print all changes to the family "AnyRvent::Fantasy::Module". |
|
|
1081 | |
|
|
1082 | my $guard = db_mon AnyRvent::Fantasy::Module => sub { |
|
|
1083 | my ($family, $a, $c, $d) = @_; |
|
|
1084 | |
|
|
1085 | print "+$_=$family->{$_}\n" for @$a; |
|
|
1086 | print "*$_=$family->{$_}\n" for @$c; |
|
|
1087 | print "-$_=$family->{$_}\n" for @$d; |
|
|
1088 | }; |
|
|
1089 | |
|
|
1090 | =cut |
|
|
1091 | |
|
|
1092 | =back |
|
|
1093 | |
880 | =head1 AnyEvent::MP vs. Distributed Erlang |
1094 | =head1 AnyEvent::MP vs. Distributed Erlang |
881 | |
1095 | |
882 | AnyEvent::MP got lots of its ideas from distributed Erlang (Erlang node |
1096 | AnyEvent::MP got lots of its ideas from distributed Erlang (Erlang node |
883 | == aemp node, Erlang process == aemp port), so many of the documents and |
1097 | == aemp node, Erlang process == aemp port), so many of the documents and |
884 | programming techniques employed by Erlang apply to AnyEvent::MP. Here is a |
1098 | programming techniques employed by Erlang apply to AnyEvent::MP. Here is a |
… | |
… | |
1038 | Keeping your messages simple, concentrating on data structures rather than |
1252 | Keeping your messages simple, concentrating on data structures rather than |
1039 | objects, will keep your messages clean, tidy and efficient. |
1253 | objects, will keep your messages clean, tidy and efficient. |
1040 | |
1254 | |
1041 | =back |
1255 | =back |
1042 | |
1256 | |
|
|
1257 | =head1 PORTING FROM AnyEvent::MP VERSION 1.X |
|
|
1258 | |
|
|
1259 | AEMP version 2 has three major incompatible changes compared to version 1: |
|
|
1260 | |
|
|
1261 | =over 4 |
|
|
1262 | |
|
|
1263 | =item AnyEvent::MP::Global no longer has group management functions. |
|
|
1264 | |
|
|
1265 | AnyEvent::MP now comes with a distributed database that is more |
|
|
1266 | powerful. It's database families map closely to ports, but the API has |
|
|
1267 | minor differences: |
|
|
1268 | |
|
|
1269 | grp_reg $group, $port # old |
|
|
1270 | db_reg $group, $port # new |
|
|
1271 | |
|
|
1272 | $list = grp_get $group # old |
|
|
1273 | db_keys $group, sub { my $list = shift } # new |
|
|
1274 | |
|
|
1275 | grp_mon $group, $cb->(\@ports, $add, $del) # old |
|
|
1276 | db_mon $group, $cb->(\%ports, $add, $change, $del) # new |
|
|
1277 | |
|
|
1278 | C<grp_reg> is a no-brainer (just replace by C<db_reg>), but C<grp_get> |
|
|
1279 | is no longer instant, because the local node might not have a copy of |
|
|
1280 | the group. This can be partially remedied by using C<db_mon> to keep an |
|
|
1281 | updated copy of the group: |
|
|
1282 | |
|
|
1283 | my $local_group_copy; |
|
|
1284 | db_mon $group => sub { $local_group_copy = shift }; |
|
|
1285 | |
|
|
1286 | # no keys %$local_group_copy always returns the most up-to-date |
|
|
1287 | # list of ports in the group. |
|
|
1288 | |
|
|
1289 | C<grp_mon> can almost be replaced by C<db_mon>: |
|
|
1290 | |
|
|
1291 | db_mon $group => sub { |
|
|
1292 | my ($ports, $add, $chg, $lde) = @_; |
|
|
1293 | $ports = [keys %$ports]; |
|
|
1294 | |
|
|
1295 | # now $ports, $add and $del are the same as |
|
|
1296 | # were originally passed by grp_mon. |
|
|
1297 | ... |
|
|
1298 | }; |
|
|
1299 | |
|
|
1300 | =item Nodes not longer connect to all other nodes. |
|
|
1301 | |
|
|
1302 | In AEMP 1.x, every node automatically loads the L<AnyEvent::MP::Global> |
|
|
1303 | module, which in turn would create connections to all other nodes in the |
|
|
1304 | network (helped by the seed nodes). |
|
|
1305 | |
|
|
1306 | In version 2.x, global nodes still connect to all other global nodes, but |
|
|
1307 | other nodes don't - now every node either is a global node itself, or |
|
|
1308 | attaches itself to another global node. |
|
|
1309 | |
|
|
1310 | If a node isn't a global node itself, then it attaches itself to one |
|
|
1311 | of its seed nodes. If that seed node isn't a global node yet, it will |
|
|
1312 | automatically be upgraded to a global node. |
|
|
1313 | |
|
|
1314 | So in many cases, nothing needs to be changed - one just has to make sure |
|
|
1315 | that all seed nodes are meshed together with the other seed nodes (as with |
|
|
1316 | AEMP 1.x), and other nodes specify them as seed nodes. |
|
|
1317 | |
|
|
1318 | Not opening a connection to every other node is usually an advantage, |
|
|
1319 | except when you need the lower latency of an already established |
|
|
1320 | connection. To ensure a node establishes a connection to another node, |
|
|
1321 | you can monitor the node port (C<mon $node, ...>), which will attempt to |
|
|
1322 | create the connection (and notify you when the connection fails). |
|
|
1323 | |
|
|
1324 | =item Listener-less nodes (nodes without binds) are gone. |
|
|
1325 | |
|
|
1326 | And are not coming back, at least not in their old form. If no C<binds> |
|
|
1327 | are specified for a node, AnyEvent::MP now assumes a default of C<*:*>. |
|
|
1328 | |
|
|
1329 | There are vague plans to implement some form of routing domains, which |
|
|
1330 | might or might not bring back listener-less nodes, but don't count on it. |
|
|
1331 | |
|
|
1332 | The fact that most connections are now optional somewhat mitigates this, |
|
|
1333 | as a node can be effectively unreachable from the outside without any |
|
|
1334 | problems, as long as it isn't a global node and only reaches out to other |
|
|
1335 | nodes (as opposed to being contacted from other nodes). |
|
|
1336 | |
|
|
1337 | =item $AnyEvent::MP::Kernel::WARN has gone. |
|
|
1338 | |
|
|
1339 | AnyEvent has acquired a logging framework (L<AnyEvent::Log>), and AEMP now |
|
|
1340 | uses this, and so should your programs. |
|
|
1341 | |
|
|
1342 | Every module now documents what kinds of messages it generates, with |
|
|
1343 | AnyEvent::MP acting as a catch all. |
|
|
1344 | |
|
|
1345 | On the positive side, this means that instead of setting |
|
|
1346 | C<PERL_ANYEVENT_MP_WARNLEVEL>, you can get away by setting C<AE_VERBOSE>, |
|
|
1347 | much less to type. |
|
|
1348 | |
|
|
1349 | =back |
|
|
1350 | |
1043 | =head1 SEE ALSO |
1351 | =head1 SEE ALSO |
1044 | |
1352 | |
1045 | L<AnyEvent::MP::Intro> - a gentle introduction. |
1353 | L<AnyEvent::MP::Intro> - a gentle introduction. |
1046 | |
1354 | |
1047 | L<AnyEvent::MP::Kernel> - more, lower-level, stuff. |
1355 | L<AnyEvent::MP::Kernel> - more, lower-level, stuff. |