1 # ----------------------------------------------------------------
2 # Copyright (C) 2010 Equinox Software, Inc.
3 # Bill Erickson <erickson@esilibrary.com>
5 # This program is free software; you can redistribute it and/or
6 # modify it under the terms of the GNU General Public License
7 # as published by the Free Software Foundation; either version 2
8 # of the License, or (at your option) any later version.
10 # This program is distributed in the hope that it will be useful,
11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 # GNU General Public License for more details.
14 # ----------------------------------------------------------------
15 package OpenSRF::Server;
18 use OpenSRF::Transport;
19 use OpenSRF::Application;
20 use OpenSRF::Utils::Config;
21 use OpenSRF::Transport::PeerHandle;
22 use OpenSRF::Utils::SettingsClient;
23 use OpenSRF::Utils::Logger qw($logger);
24 use OpenSRF::Transport::SlimJabber::Client;
25 use POSIX qw/:sys_wait_h :errno_h/;
26 use Fcntl qw(F_GETFL F_SETFL O_NONBLOCK);
29 our $chatty = 1; # disable for production
31 use constant STATUS_PIPE_DATA_SIZE => 12;
34 my($class, $service, %args) = @_;
35 my $self = bless(\%args, $class);
37 $self->{service} = $service; # service name
38 $self->{num_children} = 0; # number of child processes
39 $self->{osrf_handle} = undef; # xmpp handle
40 $self->{routers} = []; # list of registered routers
41 $self->{active_list} = []; # list of active children
42 $self->{idle_list} = []; # list of idle children
43 $self->{pid_map} = {}; # map of child pid to child for cleaner access
45 $self->{stderr_log} = $self->{stderr_log_path} . "/${service}_stderr.log"
46 if $self->{stderr_log_path};
48 $self->{min_spare_children} ||= 0;
50 $self->{max_spare_children} = $self->{min_spare_children} + 1 if
51 $self->{max_spare_children} and
52 $self->{max_spare_children} <= $self->{min_spare_children};
57 # ----------------------------------------------------------------
58 # Disconnects from routers and waits for child processes to exit.
59 # ----------------------------------------------------------------
64 $logger->info("server: shutting down and cleaning up...");
66 # don't get sidetracked by signals while we're cleaning up.
67 # it could result in unexpected behavior with list traversal
68 $SIG{CHLD} = 'IGNORE';
70 # terminate the child processes
71 $self->kill_child($_) for
72 (@{$self->{idle_list}}, @{$self->{active_list}});
75 $self->unregister_routers;
77 $self->{osrf_handle}->disconnect;
79 # clean up our dead children
80 $self->reap_children(1);
82 exit(0) unless $no_exit;
86 # ----------------------------------------------------------------
87 # Waits on the jabber socket for inbound data from the router.
88 # Each new message is passed off to a child process for handling.
89 # At regular intervals, wake up for min/max spare child maintenance
90 # ----------------------------------------------------------------
94 $logger->set_service($self->{service});
96 $SIG{$_} = sub { $self->cleanup; } for (qw/INT TERM QUIT/);
97 $SIG{CHLD} = sub { $self->reap_children(); };
99 $self->spawn_children;
100 $self->build_osrf_handle;
101 $self->register_routers;
108 $self->{child_died} = 0;
110 my $msg = $self->{osrf_handle}->process($wait_time);
112 # we woke up for any reason, reset the wait time to allow
113 # for idle maintenance as necessary
118 if(my $child = pop(@{$self->{idle_list}})) {
120 # we have an idle child to handle the request
121 $chatty and $logger->internal("server: passing request to idle child $child");
122 push(@{$self->{active_list}}, $child);
123 $self->write_child($child, $msg);
125 } elsif($self->{num_children} < $self->{max_children}) {
127 # spawning a child to handle the request
128 $chatty and $logger->internal("server: spawning child to handle request");
129 $self->write_child($self->spawn_child(1), $msg);
133 $logger->warn("server: no children available, waiting...");
134 $self->check_status(1); # block until child is available
136 my $child = pop(@{$self->{idle_list}});
137 push(@{$self->{active_list}}, $child);
138 $self->write_child($child, $msg);
143 # don't perform idle maint immediately when woken by SIGCHLD
144 unless($self->{child_died}) {
146 # when we hit equilibrium, there's no need for regular
147 # maintenance, so set wait_time to 'forever'
149 !$self->perform_idle_maintenance and # no maintenance performed this time
150 @{$self->{active_list}} == 0; # no active children
156 # ----------------------------------------------------------------
157 # Launch a new spare child or kill an extra spare child. To
158 # prevent large-scale spawning or die-offs, spawn or kill only
159 # 1 process per idle maintenance loop.
160 # Returns true if any idle maintenance occurred, 0 otherwise
161 # ----------------------------------------------------------------
162 sub perform_idle_maintenance {
165 $chatty and $logger->internal(
167 "server: %d idle, %d active, %d min_spare, %d max_spare in idle maintenance",
168 scalar(@{$self->{idle_list}}),
169 scalar(@{$self->{active_list}}),
170 $self->{min_spare_children},
171 $self->{max_spare_children}
175 # spawn 1 spare child per maintenance loop if necessary
176 if( $self->{min_spare_children} and
177 $self->{num_children} < $self->{max_children} and
178 scalar(@{$self->{idle_list}}) < $self->{min_spare_children} ) {
180 $chatty and $logger->internal("server: spawning spare child");
184 # kill 1 excess spare child per maintenance loop if necessary
185 } elsif($self->{max_spare_children} and
186 $self->{num_children} > $self->{min_children} and
187 scalar(@{$self->{idle_list}}) > $self->{max_spare_children} ) {
189 $chatty and $logger->internal("server: killing spare child");
199 my $child = shift || pop(@{$self->{idle_list}}) or return;
200 $chatty and $logger->internal("server: killing child $child");
201 kill('TERM', $child->{pid});
204 # ----------------------------------------------------------------
205 # Jabber connection inbound message arrive on.
206 # ----------------------------------------------------------------
207 sub build_osrf_handle {
210 my $conf = OpenSRF::Utils::Config->current;
211 my $username = $conf->bootstrap->username;
212 my $password = $conf->bootstrap->passwd;
213 my $domain = $conf->bootstrap->domain;
214 my $port = $conf->bootstrap->port;
215 my $resource = $self->{service} . '_listener_' . $conf->env->hostname;
217 $logger->debug("server: inbound connecting as $username\@$domain/$resource on port $port");
219 $self->{osrf_handle} =
220 OpenSRF::Transport::SlimJabber::Client->new(
221 username => $username,
222 resource => $resource,
223 password => $password,
228 $self->{osrf_handle}->initialize;
232 # ----------------------------------------------------------------
233 # Sends request data to a child process
234 # ----------------------------------------------------------------
236 my($self, $child, $msg) = @_;
237 my $xml = $msg->to_xml;
238 syswrite($child->{pipe_to_child}, $xml);
241 # ----------------------------------------------------------------
242 # Checks to see if any child process has reported its availability
243 # In blocking mode, blocks until a child has reported.
244 # ----------------------------------------------------------------
246 my($self, $block) = @_;
248 return unless @{$self->{active_list}};
250 my $read_set = IO::Select->new;
251 $read_set->add($_->{pipe_to_child}) for @{$self->{active_list}};
257 # if can_read or sysread is interrupted while bloking, go back and
258 # wait again until we have at least 1 free child
260 if(my @handles = $read_set->can_read(($block) ? undef : 0)) {
262 for my $pipe (@handles) {
263 sysread($pipe, $pid, STATUS_PIPE_DATA_SIZE) or next;
264 push(@pids, int($pid));
268 last unless $block and !@pids;
273 $chatty and $logger->internal("server: ".scalar(@pids)." children reporting for duty: (@pids)");
278 # move the children from the active list to the idle list
279 for my $proc (@{$self->{active_list}}) {
280 if(grep { $_ == $proc->{pid} } @pids) {
281 push(@{$self->{idle_list}}, $proc);
283 push(@new_actives, $proc);
287 $self->{active_list} = [@new_actives];
289 $chatty and $logger->internal(sprintf(
290 "server: %d idle and %d active children after status update",
291 scalar(@{$self->{idle_list}}), scalar(@{$self->{active_list}})));
294 # ----------------------------------------------------------------
295 # Cleans up any child processes that have exited.
296 # In shutdown mode, block until all children have washed ashore
297 # ----------------------------------------------------------------
299 my($self, $shutdown) = @_;
300 $self->{child_died} = 1;
304 my $pid = waitpid(-1, ($shutdown) ? 0 : WNOHANG);
307 $chatty and $logger->internal("server: reaping child $pid");
309 my $child = $self->{pid_map}->{$pid};
311 close($child->{pipe_to_parent});
312 close($child->{pipe_to_child});
314 $self->{active_list} = [ grep { $_->{pid} != $pid } @{$self->{active_list}} ];
315 $self->{idle_list} = [ grep { $_->{pid} != $pid } @{$self->{idle_list}} ];
317 $self->{num_children}--;
318 delete $self->{pid_map}->{$pid};
319 delete $child->{$_} for keys %$child; # destroy with a vengeance
322 $self->spawn_children unless $shutdown;
324 $chatty and $logger->internal(sprintf(
325 "server: %d idle and %d active children after reap_children",
326 scalar(@{$self->{idle_list}}), scalar(@{$self->{active_list}})));
330 # ----------------------------------------------------------------
331 # Spawn up to max_children processes
332 # ----------------------------------------------------------------
335 $self->spawn_child while $self->{num_children} < $self->{min_children};
338 # ----------------------------------------------------------------
339 # Spawns a new child. If $active is set, the child goes directly
340 # into the active_list.
341 # ----------------------------------------------------------------
343 my($self, $active) = @_;
345 my $child = OpenSRF::Server::Child->new($self);
347 # socket for sending message data to the child
349 $child->{pipe_to_child},
350 $child->{pipe_to_parent},
351 AF_UNIX, SOCK_STREAM, PF_UNSPEC)) {
352 $logger->error("server: error creating data socketpair: $!");
356 $child->{pipe_to_child}->autoflush(1);
357 $child->{pipe_to_parent}->autoflush(1);
359 $child->{pid} = fork();
361 if($child->{pid}) { # parent process
362 $self->{num_children}++;
363 $self->{pid_map}->{$child->{pid}} = $child;
366 push(@{$self->{active_list}}, $child);
368 push(@{$self->{idle_list}}, $child);
371 $chatty and $logger->internal("server: server spawned child $child with ".$self->{num_children}." total children");
375 } else { # child process
377 $SIG{$_} = 'DEFAULT' for (qw/INT TERM QUIT HUP/);
379 if($self->{stderr_log}) {
381 $chatty and $logger->internal("server: redirecting STDERR to " . $self->{stderr_log});
384 unless( open(STDERR, '>>' . $self->{stderr_log}) ) {
385 $logger->error("server: unable to open STDERR log file: " . $self->{stderr_log} . " : $@");
386 open STDERR, '>/dev/null'; # send it back to /dev/null
394 OpenSRF::Transport::PeerHandle->retrieve->disconnect;
396 $logger->error("server: child process died: $@") if $@;
401 # ----------------------------------------------------------------
402 # Sends the register command to the configured routers
403 # ----------------------------------------------------------------
404 sub register_routers {
407 my $conf = OpenSRF::Utils::Config->current;
408 my $routers = $conf->bootstrap->routers;
409 my $router_name = $conf->bootstrap->router_name;
412 for my $router (@$routers) {
415 if( !$router->{services} ||
416 !$router->{services}->{service} ||
418 ref($router->{services}->{service}) eq 'ARRAY' and
419 grep { $_ eq $self->{service} } @{$router->{services}->{service}}
420 ) || $router->{services}->{service} eq $self->{service}) {
422 my $name = $router->{name};
423 my $domain = $router->{domain};
424 push(@targets, "$name\@$domain/router");
428 push(@targets, "$router_name\@$router/router");
433 $logger->info("server: registering with router $_");
434 $self->{osrf_handle}->send(
436 body => 'registering',
437 router_command => 'register',
438 router_class => $self->{service}
442 $self->{routers} = \@targets;
445 # ----------------------------------------------------------------
446 # Sends the unregister command to any routers we have registered
448 # ----------------------------------------------------------------
449 sub unregister_routers {
451 return unless $self->{osrf_handle}->tcp_connected;
453 for my $router (@{$self->{routers}}) {
454 $logger->info("server: disconnecting from router $router");
455 $self->{osrf_handle}->send(
457 body => "unregistering",
458 router_command => "unregister",
459 router_class => $self->{service}
465 package OpenSRF::Server::Child;
468 use OpenSRF::Transport;
469 use OpenSRF::Application;
470 use OpenSRF::Transport::PeerHandle;
471 use OpenSRF::Transport::SlimJabber::XMPPMessage;
472 use OpenSRF::Utils::Logger qw($logger);
473 use OpenSRF::DomainObject::oilsResponse qw/:status/;
474 use Fcntl qw(F_GETFL F_SETFL O_NONBLOCK);
475 use Time::HiRes qw(time);
476 use POSIX qw/:sys_wait_h :errno_h/;
478 use overload '""' => sub { return '[' . shift()->{pid} . ']'; };
481 my($class, $parent) = @_;
482 my $self = bless({}, $class);
483 $self->{pid} = 0; # my process ID
484 $self->{parent} = $parent; # Controller parent process
485 $self->{num_requests} = 0; # total serviced requests
491 my $flags = fcntl($fh, F_GETFL, 0);
492 fcntl($fh, F_SETFL, $flags | O_NONBLOCK);
497 my $flags = fcntl($fh, F_GETFL, 0);
498 $flags &= ~O_NONBLOCK;
499 fcntl($fh, F_SETFL, $flags);
502 # ----------------------------------------------------------------
503 # Connects to Jabber and runs the application child_init
504 # ----------------------------------------------------------------
507 my $service = $self->{parent}->{service};
508 $0 = "OpenSRF Drone [$service]";
509 OpenSRF::Transport::PeerHandle->construct($service);
510 OpenSRF::Application->application_implementation->child_init
511 if (OpenSRF::Application->application_implementation->can('child_init'));
514 # ----------------------------------------------------------------
515 # Waits for messages from the parent process, handles the message,
516 # then goes into the keepalive loop if this is a stateful session.
517 # When max_requests is hit, the process exits.
518 # ----------------------------------------------------------------
521 my $network = OpenSRF::Transport::PeerHandle->retrieve;
523 # main child run loop. Ends when this child hits max requests.
526 my $data = $self->wait_for_request or next;
528 # Update process name to show activity
532 # Discard extraneous data from the jabber socket
533 if(!$network->flush_socket()) {
534 $logger->error("server: network disconnected! child dropping request and exiting: $data");
538 my $session = OpenSRF::Transport->handler(
539 $self->{parent}->{service},
540 OpenSRF::Transport::SlimJabber::XMPPMessage->new(xml => $data)
543 $self->keepalive_loop($session);
545 last if ++$self->{num_requests} == $self->{parent}->{max_requests};
547 # Tell the parent process we are available to process requests
550 # Repair process name
554 $chatty and $logger->internal("server: child process shutting down after reaching max_requests");
556 OpenSRF::Application->application_implementation->child_exit
557 if (OpenSRF::Application->application_implementation->can('child_exit'));
560 # ----------------------------------------------------------------
561 # waits for a request data on the parent pipe and returns it.
562 # ----------------------------------------------------------------
563 sub wait_for_request {
567 my $read_size = 1024;
571 # Start out blocking, when data is available, read it all
574 my $n = sysread($self->{pipe_to_parent}, $buf, $read_size);
577 $logger->error("server: error reading data pipe: $!") unless EAGAIN == $!;
581 last if $n <= 0; # no data left to read
585 last if $n < $read_size; # done reading all data
587 $self->set_nonblock($self->{pipe_to_parent}) unless $nonblock;
591 $self->set_block($self->{pipe_to_parent}) if $nonblock;
596 # ----------------------------------------------------------------
597 # If this is a stateful opensrf session, wait up to $keepalive
598 # seconds for subsequent requests from the client
599 # ----------------------------------------------------------------
601 my($self, $session) = @_;
602 my $keepalive = $self->{parent}->{keepalive};
604 while($session->state and $session->state == $session->CONNECTED) {
606 unless( $session->queue_wait($keepalive) ) {
608 # client failed to disconnect before timeout
609 $logger->info("server: no request was received in $keepalive seconds, exiting stateful session");
611 my $res = OpenSRF::DomainObject::oilsConnectStatus->new(
612 status => "Disconnected on timeout",
613 statusCode => STATUS_TIMEOUT
616 $session->status($res);
617 $session->state($session->DISCONNECTED);
622 $chatty and $logger->internal("server: child done with request(s)");
626 # ----------------------------------------------------------------
627 # Report our availability to our parent process
628 # ----------------------------------------------------------------
632 $self->{pipe_to_parent},
633 sprintf("%*s", OpenSRF::Server::STATUS_PIPE_DATA_SIZE, $self->{pid})