… | |
… | |
47 | # execute callbacks in $SELF port context |
47 | # execute callbacks in $SELF port context |
48 | my $timer = AE::timer 1, 0, psub { |
48 | my $timer = AE::timer 1, 0, psub { |
49 | die "kill the port, delayed"; |
49 | die "kill the port, delayed"; |
50 | }; |
50 | }; |
51 | |
51 | |
|
|
52 | # distributed database - modification |
|
|
53 | db_set $family => $subkey [=> $value] # add a subkey |
|
|
54 | db_del $family => $subkey... # delete one or more subkeys |
|
|
55 | db_reg $family => $port [=> $value] # register a port |
|
|
56 | |
|
|
57 | # distributed database - queries |
|
|
58 | db_family $family => $cb->(\%familyhash) |
|
|
59 | db_keys $family => $cb->(\@keys) |
|
|
60 | db_values $family => $cb->(\@values) |
|
|
61 | |
|
|
62 | # distributed database - monitoring a family |
|
|
63 | db_mon $family => $cb->(\%familyhash, \@added, \@changed, \@deleted) |
|
|
64 | |
52 | =head1 DESCRIPTION |
65 | =head1 DESCRIPTION |
53 | |
66 | |
54 | This module (-family) implements a simple message passing framework. |
67 | This module (-family) implements a simple message passing framework. |
55 | |
68 | |
56 | Despite its simplicity, you can securely message other processes running |
69 | Despite its simplicity, you can securely message other processes running |
… | |
… | |
105 | each other. To do this, nodes should listen on one or more local transport |
118 | each other. To do this, nodes should listen on one or more local transport |
106 | endpoints - binds. |
119 | endpoints - binds. |
107 | |
120 | |
108 | Currently, only standard C<ip:port> specifications can be used, which |
121 | Currently, only standard C<ip:port> specifications can be used, which |
109 | specify TCP ports to listen on. So a bind is basically just a tcp socket |
122 | specify TCP ports to listen on. So a bind is basically just a tcp socket |
110 | in listening mode thta accepts conenctions form other nodes. |
123 | in listening mode that accepts connections from other nodes. |
111 | |
124 | |
112 | =item seed nodes |
125 | =item seed nodes |
113 | |
126 | |
114 | When a node starts, it knows nothing about the network it is in - it |
127 | When a node starts, it knows nothing about the network it is in - it |
115 | needs to connect to at least one other node that is already in the |
128 | needs to connect to at least one other node that is already in the |
116 | network. These other nodes are called "seed nodes". |
129 | network. These other nodes are called "seed nodes". |
117 | |
130 | |
118 | Seed nodes themselves are not special - they are seed nodes only because |
131 | Seed nodes themselves are not special - they are seed nodes only because |
119 | some other node I<uses> them as such, but any node can be used as seed |
132 | some other node I<uses> them as such, but any node can be used as seed |
120 | node for other nodes, and eahc node cna use a different set of seed nodes. |
133 | node for other nodes, and eahc node can use a different set of seed nodes. |
121 | |
134 | |
122 | In addition to discovering the network, seed nodes are also used to |
135 | In addition to discovering the network, seed nodes are also used to |
123 | maintain the network - all nodes using the same seed node form are part of |
136 | maintain the network - all nodes using the same seed node are part of the |
124 | the same network. If a network is split into multiple subnets because e.g. |
137 | same network. If a network is split into multiple subnets because e.g. the |
125 | the network link between the parts goes down, then using the same seed |
138 | network link between the parts goes down, then using the same seed nodes |
126 | nodes for all nodes ensures that eventually the subnets get merged again. |
139 | for all nodes ensures that eventually the subnets get merged again. |
127 | |
140 | |
128 | Seed nodes are expected to be long-running, and at least one seed node |
141 | Seed nodes are expected to be long-running, and at least one seed node |
129 | should always be available. They should also be relatively responsive - a |
142 | should always be available. They should also be relatively responsive - a |
130 | seed node that blocks for long periods will slow down everybody else. |
143 | seed node that blocks for long periods will slow down everybody else. |
131 | |
144 | |
… | |
… | |
155 | |
168 | |
156 | Any node that loads the L<AnyEvent::MP::Global> module becomes a global |
169 | Any node that loads the L<AnyEvent::MP::Global> module becomes a global |
157 | node and tries to keep connections to all other nodes. So while it can |
170 | node and tries to keep connections to all other nodes. So while it can |
158 | make sense to make every node "global" in small networks, it usually makes |
171 | make sense to make every node "global" in small networks, it usually makes |
159 | sense to only make seed nodes into global nodes in large networks (nodes |
172 | sense to only make seed nodes into global nodes in large networks (nodes |
160 | keep connections to seed nodes and global nodes, so makign them the same |
173 | keep connections to seed nodes and global nodes, so making them the same |
161 | reduces overhead). |
174 | reduces overhead). |
162 | |
175 | |
163 | =back |
176 | =back |
164 | |
177 | |
165 | =head1 VARIABLES/FUNCTIONS |
178 | =head1 VARIABLES/FUNCTIONS |
… | |
… | |
170 | |
183 | |
171 | package AnyEvent::MP; |
184 | package AnyEvent::MP; |
172 | |
185 | |
173 | use AnyEvent::MP::Config (); |
186 | use AnyEvent::MP::Config (); |
174 | use AnyEvent::MP::Kernel; |
187 | use AnyEvent::MP::Kernel; |
175 | use AnyEvent::MP::Kernel qw(%NODE %PORT %PORT_DATA $UNIQ $RUNIQ $ID); |
188 | use AnyEvent::MP::Kernel qw( |
|
|
189 | %NODE %PORT %PORT_DATA $UNIQ $RUNIQ $ID |
|
|
190 | add_node load_func |
|
|
191 | |
|
|
192 | NODE $NODE |
|
|
193 | configure |
|
|
194 | node_of port_is_local |
|
|
195 | snd kil |
|
|
196 | db_set db_del |
|
|
197 | db_mon db_family db_keys db_values |
|
|
198 | ); |
176 | |
199 | |
177 | use common::sense; |
200 | use common::sense; |
178 | |
201 | |
179 | use Carp (); |
202 | use Carp (); |
180 | |
203 | |
… | |
… | |
184 | use base "Exporter"; |
207 | use base "Exporter"; |
185 | |
208 | |
186 | our $VERSION = $AnyEvent::MP::Config::VERSION; |
209 | our $VERSION = $AnyEvent::MP::Config::VERSION; |
187 | |
210 | |
188 | our @EXPORT = qw( |
211 | our @EXPORT = qw( |
189 | NODE $NODE *SELF node_of after |
212 | NODE $NODE |
190 | configure |
213 | configure |
|
|
214 | node_of port_is_local |
|
|
215 | snd kil |
|
|
216 | db_set db_del |
|
|
217 | db_mon db_family db_keys db_values |
|
|
218 | |
|
|
219 | *SELF |
|
|
220 | |
191 | snd rcv mon mon_guard kil psub peval spawn cal |
221 | port rcv mon mon_guard psub peval spawn cal |
192 | port |
|
|
193 | db_set db_del db_reg |
222 | db_set db_del db_reg |
194 | db_mon db_family db_keys db_values |
223 | db_mon db_family db_keys db_values |
|
|
224 | |
|
|
225 | after |
195 | ); |
226 | ); |
196 | |
227 | |
197 | our $SELF; |
228 | our $SELF; |
198 | |
229 | |
199 | sub _self_die() { |
230 | sub _self_die() { |
… | |
… | |
210 | |
241 | |
211 | =item $nodeid = node_of $port |
242 | =item $nodeid = node_of $port |
212 | |
243 | |
213 | Extracts and returns the node ID from a port ID or a node ID. |
244 | Extracts and returns the node ID from a port ID or a node ID. |
214 | |
245 | |
|
|
246 | =item $is_local = port_is_local $port |
|
|
247 | |
|
|
248 | Returns true iff the port is a local port. |
|
|
249 | |
215 | =item configure $profile, key => value... |
250 | =item configure $profile, key => value... |
216 | |
251 | |
217 | =item configure key => value... |
252 | =item configure key => value... |
218 | |
253 | |
219 | Before a node can talk to other nodes on the network (i.e. enter |
254 | Before a node can talk to other nodes on the network (i.e. enter |
… | |
… | |
230 | =over 4 |
265 | =over 4 |
231 | |
266 | |
232 | =item norc => $boolean (default false) |
267 | =item norc => $boolean (default false) |
233 | |
268 | |
234 | If true, then the rc file (e.g. F<~/.perl-anyevent-mp>) will I<not> |
269 | If true, then the rc file (e.g. F<~/.perl-anyevent-mp>) will I<not> |
235 | be consulted - all configuraiton options must be specified in the |
270 | be consulted - all configuration options must be specified in the |
236 | C<configure> call. |
271 | C<configure> call. |
237 | |
272 | |
238 | =item force => $boolean (default false) |
273 | =item force => $boolean (default false) |
239 | |
274 | |
240 | IF true, then the values specified in the C<configure> will take |
275 | IF true, then the values specified in the C<configure> will take |
241 | precedence over any values configured via the rc file. The default is for |
276 | precedence over any values configured via the rc file. The default is for |
242 | the rc file to override any options specified in the program. |
277 | the rc file to override any options specified in the program. |
243 | |
|
|
244 | =item secure => $pass->(@msg) |
|
|
245 | |
|
|
246 | In addition to specifying a boolean, you can specify a code reference that |
|
|
247 | is called for every code execution attempt - the execution request is |
|
|
248 | granted iff the callback returns a true value. |
|
|
249 | |
|
|
250 | Most of the time the callback should look only at |
|
|
251 | C<$AnyEvent::MP::Kernel::SRCNODE> to make a decision, and not at the |
|
|
252 | actual message (which can be about anything, and is mostly provided for |
|
|
253 | diagnostic purposes). |
|
|
254 | |
|
|
255 | See F<semp setsecure> for more info. |
|
|
256 | |
278 | |
257 | =back |
279 | =back |
258 | |
280 | |
259 | =over 4 |
281 | =over 4 |
260 | |
282 | |
… | |
… | |
289 | |
311 | |
290 | =item step 2, bind listener sockets |
312 | =item step 2, bind listener sockets |
291 | |
313 | |
292 | The next step is to look up the binds in the profile, followed by binding |
314 | The next step is to look up the binds in the profile, followed by binding |
293 | aemp protocol listeners on all binds specified (it is possible and valid |
315 | aemp protocol listeners on all binds specified (it is possible and valid |
294 | to have no binds, meaning that the node cannot be contacted form the |
316 | to have no binds, meaning that the node cannot be contacted from the |
295 | outside. This means the node cannot talk to other nodes that also have no |
317 | outside. This means the node cannot talk to other nodes that also have no |
296 | binds, but it can still talk to all "normal" nodes). |
318 | binds, but it can still talk to all "normal" nodes). |
297 | |
319 | |
298 | If the profile does not specify a binds list, then a default of C<*> is |
320 | If the profile does not specify a binds list, then a default of C<*> is |
299 | used, meaning the node will bind on a dynamically-assigned port on every |
321 | used, meaning the node will bind on a dynamically-assigned port on every |
… | |
… | |
464 | |
486 | |
465 | sub rcv($@) { |
487 | sub rcv($@) { |
466 | my $port = shift; |
488 | my $port = shift; |
467 | my ($nodeid, $portid) = split /#/, $port, 2; |
489 | my ($nodeid, $portid) = split /#/, $port, 2; |
468 | |
490 | |
469 | $NODE{$nodeid} == $NODE{""} |
491 | $nodeid eq $NODE |
470 | or Carp::croak "$port: rcv can only be called on local ports, caught"; |
492 | or Carp::croak "$port: rcv can only be called on local ports, caught"; |
471 | |
493 | |
472 | while (@_) { |
494 | while (@_) { |
473 | if (ref $_[0]) { |
495 | if (ref $_[0]) { |
474 | if (my $self = $PORT_DATA{$portid}) { |
496 | if (my $self = $PORT_DATA{$portid}) { |
… | |
… | |
518 | } |
540 | } |
519 | |
541 | |
520 | =item peval $port, $coderef[, @args] |
542 | =item peval $port, $coderef[, @args] |
521 | |
543 | |
522 | Evaluates the given C<$codref> within the contetx of C<$port>, that is, |
544 | Evaluates the given C<$codref> within the contetx of C<$port>, that is, |
523 | when the code throews an exception the C<$port> will be killed. |
545 | when the code throws an exception the C<$port> will be killed. |
524 | |
546 | |
525 | Any remaining args will be passed to the callback. Any return values will |
547 | Any remaining args will be passed to the callback. Any return values will |
526 | be returned to the caller. |
548 | be returned to the caller. |
527 | |
549 | |
528 | This is useful when you temporarily want to execute code in the context of |
550 | This is useful when you temporarily want to execute code in the context of |
… | |
… | |
1033 | =item db_values $family => $cb->(\@values) |
1055 | =item db_values $family => $cb->(\@values) |
1034 | |
1056 | |
1035 | Same as C<db_family>, except it only queries the family I<values> and passes them |
1057 | Same as C<db_family>, except it only queries the family I<values> and passes them |
1036 | as array reference to the callback. |
1058 | as array reference to the callback. |
1037 | |
1059 | |
1038 | =item $guard = db_mon $family => $cb->($familyhash, \@added, \@changed, \@deleted) |
1060 | =item $guard = db_mon $family => $cb->(\%familyhash, \@added, \@changed, \@deleted) |
1039 | |
1061 | |
1040 | Creates a monitor on the given database family. Each time a key is set |
1062 | Creates a monitor on the given database family. Each time a key is |
1041 | or or is deleted the callback is called with a hash containing the |
1063 | set or is deleted the callback is called with a hash containing the |
1042 | database family and three lists of added, changed and deleted subkeys, |
1064 | database family and three lists of added, changed and deleted subkeys, |
1043 | respectively. If no keys have changed then the array reference might be |
1065 | respectively. If no keys have changed then the array reference might be |
1044 | C<undef> or even missing. |
1066 | C<undef> or even missing. |
1045 | |
1067 | |
1046 | If not called in void context, a guard object is returned that, when |
1068 | If not called in void context, a guard object is returned that, when |
… | |
… | |
1074 | return unless %$family; |
1096 | return unless %$family; |
1075 | undef $guard; |
1097 | undef $guard; |
1076 | print "My::Module::workers now nonempty\n"; |
1098 | print "My::Module::workers now nonempty\n"; |
1077 | }; |
1099 | }; |
1078 | |
1100 | |
1079 | Example: print all changes to the family "AnyRvent::Fantasy::Module". |
1101 | Example: print all changes to the family "AnyEvent::Fantasy::Module". |
1080 | |
1102 | |
1081 | my $guard = db_mon AnyRvent::Fantasy::Module => sub { |
1103 | my $guard = db_mon AnyEvent::Fantasy::Module => sub { |
1082 | my ($family, $a, $c, $d) = @_; |
1104 | my ($family, $a, $c, $d) = @_; |
1083 | |
1105 | |
1084 | print "+$_=$family->{$_}\n" for @$a; |
1106 | print "+$_=$family->{$_}\n" for @$a; |
1085 | print "*$_=$family->{$_}\n" for @$c; |
1107 | print "*$_=$family->{$_}\n" for @$c; |
1086 | print "-$_=$family->{$_}\n" for @$d; |
1108 | print "-$_=$family->{$_}\n" for @$d; |
… | |
… | |
1137 | filter messages without dequeuing them. |
1159 | filter messages without dequeuing them. |
1138 | |
1160 | |
1139 | This is not a philosophical difference, but simply stems from AnyEvent::MP |
1161 | This is not a philosophical difference, but simply stems from AnyEvent::MP |
1140 | being event-based, while Erlang is process-based. |
1162 | being event-based, while Erlang is process-based. |
1141 | |
1163 | |
1142 | You cna have a look at L<Coro::MP> for a more Erlang-like process model on |
1164 | You can have a look at L<Coro::MP> for a more Erlang-like process model on |
1143 | top of AEMP and Coro threads. |
1165 | top of AEMP and Coro threads. |
1144 | |
1166 | |
1145 | =item * Erlang sends are synchronous, AEMP sends are asynchronous. |
1167 | =item * Erlang sends are synchronous, AEMP sends are asynchronous. |
1146 | |
1168 | |
1147 | Sending messages in Erlang is synchronous and blocks the process until |
1169 | Sending messages in Erlang is synchronous and blocks the process until |
1148 | a conenction has been established and the message sent (and so does not |
1170 | a connection has been established and the message sent (and so does not |
1149 | need a queue that can overflow). AEMP sends return immediately, connection |
1171 | need a queue that can overflow). AEMP sends return immediately, connection |
1150 | establishment is handled in the background. |
1172 | establishment is handled in the background. |
1151 | |
1173 | |
1152 | =item * Erlang suffers from silent message loss, AEMP does not. |
1174 | =item * Erlang suffers from silent message loss, AEMP does not. |
1153 | |
1175 | |
… | |
… | |
1292 | C<grp_mon> can be replaced by C<db_mon> with minor changes - C<db_mon> |
1314 | C<grp_mon> can be replaced by C<db_mon> with minor changes - C<db_mon> |
1293 | passes a hash as first argument, and an extra C<$chg> argument that can be |
1315 | passes a hash as first argument, and an extra C<$chg> argument that can be |
1294 | ignored: |
1316 | ignored: |
1295 | |
1317 | |
1296 | db_mon $group => sub { |
1318 | db_mon $group => sub { |
1297 | my ($ports, $add, $chg, $lde) = @_; |
1319 | my ($ports, $add, $chg, $del) = @_; |
1298 | $ports = [keys %$ports]; |
1320 | $ports = [keys %$ports]; |
1299 | |
1321 | |
1300 | # now $ports, $add and $del are the same as |
1322 | # now $ports, $add and $del are the same as |
1301 | # were originally passed by grp_mon. |
1323 | # were originally passed by grp_mon. |
1302 | ... |
1324 | ... |
… | |
… | |
1355 | |
1377 | |
1356 | =back |
1378 | =back |
1357 | |
1379 | |
1358 | =head1 LOGGING |
1380 | =head1 LOGGING |
1359 | |
1381 | |
1360 | AnyEvent::MP does not normally log anything by itself, but sinc eit is the |
1382 | AnyEvent::MP does not normally log anything by itself, but since it is the |
1361 | root of the contetx hierarchy for AnyEvent::MP modules, it will receive |
1383 | root of the contetx hierarchy for AnyEvent::MP modules, it will receive |
1362 | all log messages by submodules. |
1384 | all log messages by submodules. |
1363 | |
1385 | |
1364 | =head1 SEE ALSO |
1386 | =head1 SEE ALSO |
1365 | |
1387 | |