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);
132 $logger->warn("server: no children available, waiting... consider increasing " .
133 "max_children for this application higher than $self->{max_children} ".
134 "in the OpenSRF configuration if this message occurs frequently");
135 $self->check_status(1); # block until child is available
137 my $child = pop(@{$self->{idle_list}});
138 push(@{$self->{active_list}}, $child);
139 $self->write_child($child, $msg);
144 # don't perform idle maint immediately when woken by SIGCHLD
145 unless($self->{child_died}) {
147 # when we hit equilibrium, there's no need for regular
148 # maintenance, so set wait_time to 'forever'
150 !$self->perform_idle_maintenance and # no maintenance performed this time
151 @{$self->{active_list}} == 0; # no active children
157 # ----------------------------------------------------------------
158 # Launch a new spare child or kill an extra spare child. To
159 # prevent large-scale spawning or die-offs, spawn or kill only
160 # 1 process per idle maintenance loop.
161 # Returns true if any idle maintenance occurred, 0 otherwise
162 # ----------------------------------------------------------------
163 sub perform_idle_maintenance {
166 $chatty and $logger->internal(
168 "server: %d idle, %d active, %d min_spare, %d max_spare in idle maintenance",
169 scalar(@{$self->{idle_list}}),
170 scalar(@{$self->{active_list}}),
171 $self->{min_spare_children},
172 $self->{max_spare_children}
176 # spawn 1 spare child per maintenance loop if necessary
177 if( $self->{min_spare_children} and
178 $self->{num_children} < $self->{max_children} and
179 scalar(@{$self->{idle_list}}) < $self->{min_spare_children} ) {
181 $chatty and $logger->internal("server: spawning spare child");
185 # kill 1 excess spare child per maintenance loop if necessary
186 } elsif($self->{max_spare_children} and
187 $self->{num_children} > $self->{min_children} and
188 scalar(@{$self->{idle_list}}) > $self->{max_spare_children} ) {
190 $chatty and $logger->internal("server: killing spare child");
200 my $child = shift || pop(@{$self->{idle_list}}) or return;
201 $chatty and $logger->internal("server: killing child $child");
202 kill('TERM', $child->{pid});
205 # ----------------------------------------------------------------
206 # Jabber connection inbound message arrive on.
207 # ----------------------------------------------------------------
208 sub build_osrf_handle {
211 my $conf = OpenSRF::Utils::Config->current;
212 my $username = $conf->bootstrap->username;
213 my $password = $conf->bootstrap->passwd;
214 my $domain = $conf->bootstrap->domain;
215 my $port = $conf->bootstrap->port;
216 my $resource = $self->{service} . '_listener_' . $conf->env->hostname;
218 $logger->debug("server: inbound connecting as $username\@$domain/$resource on port $port");
220 $self->{osrf_handle} =
221 OpenSRF::Transport::SlimJabber::Client->new(
222 username => $username,
223 resource => $resource,
224 password => $password,
229 $self->{osrf_handle}->initialize;
233 # ----------------------------------------------------------------
234 # Sends request data to a child process
235 # ----------------------------------------------------------------
237 my($self, $child, $msg) = @_;
238 my $xml = $msg->to_xml;
239 syswrite($child->{pipe_to_child}, $xml);
242 # ----------------------------------------------------------------
243 # Checks to see if any child process has reported its availability
244 # In blocking mode, blocks until a child has reported.
245 # ----------------------------------------------------------------
247 my($self, $block) = @_;
249 return unless @{$self->{active_list}};
251 my $read_set = IO::Select->new;
252 $read_set->add($_->{pipe_to_child}) for @{$self->{active_list}};
258 # if can_read or sysread is interrupted while bloking, go back and
259 # wait again until we have at least 1 free child
261 if(my @handles = $read_set->can_read(($block) ? undef : 0)) {
263 for my $pipe (@handles) {
264 sysread($pipe, $pid, STATUS_PIPE_DATA_SIZE) or next;
265 push(@pids, int($pid));
269 last unless $block and !@pids;
274 $chatty and $logger->internal("server: ".scalar(@pids)." children reporting for duty: (@pids)");
279 # move the children from the active list to the idle list
280 for my $proc (@{$self->{active_list}}) {
281 if(grep { $_ == $proc->{pid} } @pids) {
282 push(@{$self->{idle_list}}, $proc);
284 push(@new_actives, $proc);
288 $self->{active_list} = [@new_actives];
290 $chatty and $logger->internal(sprintf(
291 "server: %d idle and %d active children after status update",
292 scalar(@{$self->{idle_list}}), scalar(@{$self->{active_list}})));
295 # ----------------------------------------------------------------
296 # Cleans up any child processes that have exited.
297 # In shutdown mode, block until all children have washed ashore
298 # ----------------------------------------------------------------
300 my($self, $shutdown) = @_;
301 $self->{child_died} = 1;
305 my $pid = waitpid(-1, ($shutdown) ? 0 : WNOHANG);
308 $chatty and $logger->internal("server: reaping child $pid");
310 my $child = $self->{pid_map}->{$pid};
312 close($child->{pipe_to_parent});
313 close($child->{pipe_to_child});
315 $self->{active_list} = [ grep { $_->{pid} != $pid } @{$self->{active_list}} ];
316 $self->{idle_list} = [ grep { $_->{pid} != $pid } @{$self->{idle_list}} ];
318 $self->{num_children}--;
319 delete $self->{pid_map}->{$pid};
320 delete $child->{$_} for keys %$child; # destroy with a vengeance
323 $self->spawn_children unless $shutdown;
325 $chatty and $logger->internal(sprintf(
326 "server: %d idle and %d active children after reap_children",
327 scalar(@{$self->{idle_list}}), scalar(@{$self->{active_list}})));
331 # ----------------------------------------------------------------
332 # Spawn up to max_children processes
333 # ----------------------------------------------------------------
336 $self->spawn_child while $self->{num_children} < $self->{min_children};
339 # ----------------------------------------------------------------
340 # Spawns a new child. If $active is set, the child goes directly
341 # into the active_list.
342 # ----------------------------------------------------------------
344 my($self, $active) = @_;
346 my $child = OpenSRF::Server::Child->new($self);
348 # socket for sending message data to the child
350 $child->{pipe_to_child},
351 $child->{pipe_to_parent},
352 AF_UNIX, SOCK_STREAM, PF_UNSPEC)) {
353 $logger->error("server: error creating data socketpair: $!");
357 $child->{pipe_to_child}->autoflush(1);
358 $child->{pipe_to_parent}->autoflush(1);
360 $child->{pid} = fork();
362 if($child->{pid}) { # parent process
363 $self->{num_children}++;
364 $self->{pid_map}->{$child->{pid}} = $child;
367 push(@{$self->{active_list}}, $child);
369 push(@{$self->{idle_list}}, $child);
372 $chatty and $logger->internal("server: server spawned child $child with ".$self->{num_children}." total children");
376 } else { # child process
378 $SIG{$_} = 'DEFAULT' for (qw/INT TERM QUIT HUP/);
380 if($self->{stderr_log}) {
382 $chatty and $logger->internal("server: redirecting STDERR to " . $self->{stderr_log});
385 unless( open(STDERR, '>>' . $self->{stderr_log}) ) {
386 $logger->error("server: unable to open STDERR log file: " . $self->{stderr_log} . " : $@");
387 open STDERR, '>/dev/null'; # send it back to /dev/null
395 OpenSRF::Transport::PeerHandle->retrieve->disconnect;
397 $logger->error("server: child process died: $@") if $@;
402 # ----------------------------------------------------------------
403 # Sends the register command to the configured routers
404 # ----------------------------------------------------------------
405 sub register_routers {
408 my $conf = OpenSRF::Utils::Config->current;
409 my $routers = $conf->bootstrap->routers;
410 my $router_name = $conf->bootstrap->router_name;
413 for my $router (@$routers) {
416 if( !$router->{services} ||
417 !$router->{services}->{service} ||
419 ref($router->{services}->{service}) eq 'ARRAY' and
420 grep { $_ eq $self->{service} } @{$router->{services}->{service}}
421 ) || $router->{services}->{service} eq $self->{service}) {
423 my $name = $router->{name};
424 my $domain = $router->{domain};
425 push(@targets, "$name\@$domain/router");
429 push(@targets, "$router_name\@$router/router");
434 $logger->info("server: registering with router $_");
435 $self->{osrf_handle}->send(
437 body => 'registering',
438 router_command => 'register',
439 router_class => $self->{service}
443 $self->{routers} = \@targets;
446 # ----------------------------------------------------------------
447 # Sends the unregister command to any routers we have registered
449 # ----------------------------------------------------------------
450 sub unregister_routers {
452 return unless $self->{osrf_handle}->tcp_connected;
454 for my $router (@{$self->{routers}}) {
455 $logger->info("server: disconnecting from router $router");
456 $self->{osrf_handle}->send(
458 body => "unregistering",
459 router_command => "unregister",
460 router_class => $self->{service}
466 package OpenSRF::Server::Child;
469 use OpenSRF::Transport;
470 use OpenSRF::Application;
471 use OpenSRF::Transport::PeerHandle;
472 use OpenSRF::Transport::SlimJabber::XMPPMessage;
473 use OpenSRF::Utils::Logger qw($logger);
474 use OpenSRF::DomainObject::oilsResponse qw/:status/;
475 use Fcntl qw(F_GETFL F_SETFL O_NONBLOCK);
476 use Time::HiRes qw(time);
477 use POSIX qw/:sys_wait_h :errno_h/;
479 use overload '""' => sub { return '[' . shift()->{pid} . ']'; };
482 my($class, $parent) = @_;
483 my $self = bless({}, $class);
484 $self->{pid} = 0; # my process ID
485 $self->{parent} = $parent; # Controller parent process
486 $self->{num_requests} = 0; # total serviced requests
492 my $flags = fcntl($fh, F_GETFL, 0);
493 fcntl($fh, F_SETFL, $flags | O_NONBLOCK);
498 my $flags = fcntl($fh, F_GETFL, 0);
499 $flags &= ~O_NONBLOCK;
500 fcntl($fh, F_SETFL, $flags);
503 # ----------------------------------------------------------------
504 # Connects to Jabber and runs the application child_init
505 # ----------------------------------------------------------------
508 my $service = $self->{parent}->{service};
509 $0 = "OpenSRF Drone [$service]";
510 OpenSRF::Transport::PeerHandle->construct($service);
511 OpenSRF::Application->application_implementation->child_init
512 if (OpenSRF::Application->application_implementation->can('child_init'));
515 # ----------------------------------------------------------------
516 # Waits for messages from the parent process, handles the message,
517 # then goes into the keepalive loop if this is a stateful session.
518 # When max_requests is hit, the process exits.
519 # ----------------------------------------------------------------
522 my $network = OpenSRF::Transport::PeerHandle->retrieve;
524 # main child run loop. Ends when this child hits max requests.
527 my $data = $self->wait_for_request or next;
529 # Update process name to show activity
533 # Discard extraneous data from the jabber socket
534 if(!$network->flush_socket()) {
535 $logger->error("server: network disconnected! child dropping request and exiting: $data");
539 my $session = OpenSRF::Transport->handler(
540 $self->{parent}->{service},
541 OpenSRF::Transport::SlimJabber::XMPPMessage->new(xml => $data)
544 $self->keepalive_loop($session);
546 last if ++$self->{num_requests} == $self->{parent}->{max_requests};
548 # Tell the parent process we are available to process requests
551 # Repair process name
555 $chatty and $logger->internal("server: child process shutting down after reaching max_requests");
557 OpenSRF::Application->application_implementation->child_exit
558 if (OpenSRF::Application->application_implementation->can('child_exit'));
561 # ----------------------------------------------------------------
562 # waits for a request data on the parent pipe and returns it.
563 # ----------------------------------------------------------------
564 sub wait_for_request {
568 my $read_size = 1024;
572 # Start out blocking, when data is available, read it all
575 my $n = sysread($self->{pipe_to_parent}, $buf, $read_size);
578 $logger->error("server: error reading data pipe: $!") unless EAGAIN == $!;
582 last if $n <= 0; # no data left to read
586 last if $n < $read_size; # done reading all data
588 $self->set_nonblock($self->{pipe_to_parent}) unless $nonblock;
592 $self->set_block($self->{pipe_to_parent}) if $nonblock;
597 # ----------------------------------------------------------------
598 # If this is a stateful opensrf session, wait up to $keepalive
599 # seconds for subsequent requests from the client
600 # ----------------------------------------------------------------
602 my($self, $session) = @_;
603 my $keepalive = $self->{parent}->{keepalive};
605 while($session->state and $session->state == $session->CONNECTED) {
607 unless( $session->queue_wait($keepalive) ) {
609 # client failed to disconnect before timeout
610 $logger->info("server: no request was received in $keepalive seconds, exiting stateful session");
612 my $res = OpenSRF::DomainObject::oilsConnectStatus->new(
613 status => "Disconnected on timeout",
614 statusCode => STATUS_TIMEOUT
617 $session->status($res);
618 $session->state($session->DISCONNECTED);
623 $chatty and $logger->internal("server: child done with request(s)");
627 # ----------------------------------------------------------------
628 # Report our availability to our parent process
629 # ----------------------------------------------------------------
633 $self->{pipe_to_parent},
634 sprintf("%*s", OpenSRF::Server::STATUS_PIPE_DATA_SIZE, $self->{pid})