ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/cvsroot/AnyEvent-MP/MP.pm
(Generate patch)

Comparing cvsroot/AnyEvent-MP/MP.pm (file contents):
Revision 1.130 by root, Fri Mar 9 17:05:26 2012 UTC vs.
Revision 1.136 by root, Wed Mar 21 15:22:16 2012 UTC

… …
247 247
248IF true, then the values specified in the C<configure> will take 248IF true, then the values specified in the C<configure> will take
249precedence over any values configured via the rc file. The default is for 249precedence over any values configured via the rc file. The default is for
250the rc file to override any options specified in the program. 250the rc file to override any options specified in the program.
251 251
252=item secure => $pass->($nodeid) 252=item secure => $pass->(@msg)
253 253
254In addition to specifying a boolean, you can specify a code reference that 254In addition to specifying a boolean, you can specify a code reference that
255is called for every remote execution attempt - the execution request is 255is called for every code execution attempt - the execution request is
256granted iff the callback returns a true value. 256granted iff the callback returns a true value.
257
258Most of the time the callback should look only at
259C<$AnyEvent::MP::Kernel::SRCNODE> to make a decision, and not at the
260actual message (which can be about anything, and is mostly provided for
261diagnostic purposes).
257 262
258See F<semp setsecure> for more info. 263See F<semp setsecure> for more info.
259 264
260=back 265=back
261 266
… …
398 403
399=cut 404=cut
400 405
401sub rcv($@); 406sub rcv($@);
402 407
403sub _kilme { 408my $KILME = sub {
404 die "received message on port without callback"; 409 (my $tag = substr $_[0], 0, 30) =~ s/([\x20-\x7e])/./g;
405} 410 kil $SELF, unhandled_message => "no callback found for message '$tag'";
411};
406 412
407sub port(;&) { 413sub port(;&) {
408 my $id = $UNIQ . ++$ID; 414 my $id = $UNIQ . ++$ID;
409 my $port = "$NODE#$id"; 415 my $port = "$NODE#$id";
410 416
411 rcv $port, shift || \&_kilme; 417 rcv $port, shift || $KILME;
412 418
413 $port 419 $port
414} 420}
415 421
416=item rcv $local_port, $callback->(@msg) 422=item rcv $local_port, $callback->(@msg)
… …
421 427
422The global C<$SELF> (exported by this module) contains C<$port> while 428The global C<$SELF> (exported by this module) contains C<$port> while
423executing the callback. Runtime errors during callback execution will 429executing the callback. Runtime errors during callback execution will
424result in the port being C<kil>ed. 430result in the port being C<kil>ed.
425 431
426The default callback received all messages not matched by a more specific 432The default callback receives all messages not matched by a more specific
427C<tag> match. 433C<tag> match.
428 434
429=item rcv $local_port, tag => $callback->(@msg_without_tag), ... 435=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
430 436
431Register (or replace) callbacks to be called on messages starting with the 437Register (or replace) callbacks to be called on messages starting with the
… …
732will be reported as reason C<< die => $@ >>. 738will be reported as reason C<< die => $@ >>.
733 739
734Transport/communication errors are reported as C<< transport_error => 740Transport/communication errors are reported as C<< transport_error =>
735$message >>. 741$message >>.
736 742
737=cut 743Common 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: $!";
738 754
739=item $port = spawn $node, $initfunc[, @initdata] 755=item $port = spawn $node, $initfunc[, @initdata]
740 756
741Creates a port on the node C<$node> (which can also be a port ID, in which 757Creates a port on the node C<$node> (which can also be a port ID, in which
742case it's the node where that port resides). 758case it's the node where that port resides).
… …
894=back 910=back
895 911
896=head1 DISTRIBUTED DATABASE 912=head1 DISTRIBUTED DATABASE
897 913
898AnyEvent::MP comes with a simple distributed database. The database will 914AnyEvent::MP comes with a simple distributed database. The database will
899be mirrored asynchronously at all global nodes. Other nodes bind to one of 915be mirrored asynchronously on all global nodes. Other nodes bind to one
900the global nodes for their needs. 916of the global nodes for their needs. Every node has a "local database"
917which contains all the values that are set locally. All local databases
918are merged together to form the global database, which can be queried.
901 919
902The database consists of a two-level hash - a hash contains a hash which 920The database structure is that of a two-level hash - the database hash
903contains values. 921contains hashes which contain values, similarly to a perl hash of hashes,
922i.e.:
923
924 $DATABASE{$family}{$subkey} = $value
904 925
905The top level hash key is called "family", and the second-level hash key 926The top level hash key is called "family", and the second-level hash key
906is called "subkey" or simply "key". 927is called "subkey" or simply "key".
907 928
908The family must be alphanumeric, i.e. start with a letter and consist 929The family must be alphanumeric, i.e. start with a letter and consist
… …
913with the name of the application or module using it. 934with the name of the application or module using it.
914 935
915The subkeys must be non-empty strings, with no further restrictions. 936The subkeys must be non-empty strings, with no further restrictions.
916 937
917The values should preferably be strings, but other perl scalars should 938The values should preferably be strings, but other perl scalars should
918work as well (such as undef, arrays and hashes). 939work as well (such as C<undef>, arrays and hashes).
919 940
920Every database entry is owned by one node - adding the same family/subkey 941Every database entry is owned by one node - adding the same family/subkey
921combination on multiple nodes will not cause discomfort for AnyEvent::MP, 942combination on multiple nodes will not cause discomfort for AnyEvent::MP,
922but the result might be nondeterministic, i.e. the key might have 943but the result might be nondeterministic, i.e. the key might have
923different values on different nodes. 944different values on different nodes.
… …
985Creates a monitor on the given database family. Each time a key is set 1006Creates a monitor on the given database family. Each time a key is set
986or or is deleted the callback is called with a hash containing the 1007or or is deleted the callback is called with a hash containing the
987database family and three lists of added, changed and deleted subkeys, 1008database family and three lists of added, changed and deleted subkeys,
988respectively. If no keys have changed then the array reference might be 1009respectively. If no keys have changed then the array reference might be
989C<undef> or even missing. 1010C<undef> or even missing.
1011
1012If not called in void context, a guard object is returned that, when
1013destroyed, stops the monitor.
990 1014
991The family hash reference and the key arrays belong to AnyEvent::MP and 1015The family hash reference and the key arrays belong to AnyEvent::MP and
992B<must not be modified or stored> by the callback. When in doubt, make a 1016B<must not be modified or stored> by the callback. When in doubt, make a
993copy. 1017copy.
994 1018

Diff Legend

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