1 package Object::Remote::Connection;
3 use Object::Remote::Logging qw (:log :dlog get_router);
4 use Object::Remote::Future;
5 use Object::Remote::Null;
6 use Object::Remote::Handle;
7 use Object::Remote::CodeContainer;
8 use Object::Remote::GlobProxy;
9 use Object::Remote::GlobContainer;
10 use Object::Remote::Tied;
14 use POSIX ":sys_wait_h";
15 use Module::Runtime qw(use_module);
16 use Scalar::Util qw(weaken blessed refaddr openhandle);
17 use JSON::PP qw(encode_json);
21 get_router()->exclude_forwarding;
23 #this will reap child processes as soon
24 #as they are done executing so the process
25 #table cleans up as fast as possible but
26 #anything that needs to call waitpid()
27 #in the future to get the exit value of
28 #a child will get trash results if
29 #the signal handler was running.
30 #If creating a child and getting the
31 #exit value is required then set
32 #a localized version of the signal
33 #handler for CHLD to be 'IGNORE'
34 #in the smallest block possible
35 #and outside the block send
36 #the process a CHLD signal
37 #to reap anything that may
38 #have exited while blocked
42 log_trace { "CHLD signal handler is executing" };
44 $kid = waitpid(-1, WNOHANG);
45 log_debug { "waitpid() returned '$kid'" };
47 log_trace { "CHLD signal handler is done" };
50 $SIG{PIPE} = sub { log_debug { "Got a PIPE signal" } };
54 log_debug { "Killing all child processes in the process group" };
56 #send SIGINT to the process group for our children
60 has _id => ( is => 'ro', required => 1, default => sub { our $NEXT_CONNECTION_ID++ } );
63 is => 'ro', required => 1,
67 Dlog_trace { my $id = $self->_id; "connection had send_to_fh set to $_" } $_[1];
72 is => 'ro', required => 1,
76 Dlog_trace { "trigger for read_channel has been invoked for connection $id; file handle is $_" } $ch->fh;
78 $ch->on_line_call(sub { $self->_receive(@_) });
79 $ch->on_close_call(sub {
80 log_trace { "invoking 'done' on on_close handler for connection id '$id'" };
81 $self->on_close->done(@_);
87 is => 'rw', default => sub { $_[0]->_install_future_handlers(CPS::Future->new) },
88 trigger => \&_install_future_handlers,
91 has child_pid => (is => 'ro');
93 has local_objects_by_id => (
94 is => 'ro', default => sub { {} },
95 coerce => sub { +{ %{$_[0]} } }, # shallow clone on the way in
98 has remote_objects_by_id => (
99 is => 'ro', default => sub { {} },
100 coerce => sub { +{ %{$_[0]} } }, # shallow clone on the way in
103 has outstanding_futures => (is => 'ro', default => sub { {} });
108 _deserialize => 'decode',
116 return unless defined $self->child_pid;
118 log_debug { "Setting process group of child process" };
120 setpgrp($self->child_pid, 1);
125 sub _fail_outstanding {
126 my ($self, $error) = @_;
127 Dlog_debug { "Failing outstanding futures with '$error' for connection $_" } $self->_id;
128 my $outstanding = $self->outstanding_futures;
129 $_->fail("$error\n") for values %$outstanding;
134 sub _install_future_handlers {
136 Dlog_trace { "trigger for on_close has been invoked for connection $_" } $self->_id;
139 Dlog_trace { "failing all of the outstanding futures for connection $_" } $self->_id;
140 $self->_fail_outstanding("Object::Remote connection lost: " . ($f->get)[0]);
145 sub _id_to_remote_object {
146 my ($self, $id) = @_;
147 Dlog_trace { "fetching proxy for remote object with id '$id' for connection $_" } $self->_id;
148 return bless({}, 'Object::Remote::Null') if $id eq 'NULL';
150 $self->remote_objects_by_id->{$id}
151 or Object::Remote::Handle->new(connection => $self, id => $id)
156 weaken(my $self = shift);
157 JSON::PP->new->filter_json_single_key_object(
158 __remote_object__ => sub {
159 $self->_id_to_remote_object(@_);
161 )->filter_json_single_key_object(
162 __remote_code__ => sub {
163 my $code_container = $self->_id_to_remote_object(@_);
164 sub { $code_container->call(@_) };
166 )->filter_json_single_key_object(
167 __scalar_ref__ => sub {
171 )->filter_json_single_key_object(
172 __glob_ref__ => sub {
173 my $glob_container = $self->_id_to_remote_object(@_);
174 my $handle = Symbol::gensym;
175 tie *$handle, 'Object::Remote::GlobProxy', $glob_container;
178 )->filter_json_single_key_object(
179 __local_object__ => sub {
180 $self->local_objects_by_id->{$_[0]}
182 )->filter_json_single_key_object(
183 __remote_tied_hash__ => sub {
185 tie %tied_hash, 'Object::Remote::Tied', $self->_id_to_remote_object(@_);
188 )->filter_json_single_key_object(
189 __remote_tied_array__ => sub {
191 tie @tied_array, 'Object::Remote::Tied', $self->_id_to_remote_object(@_);
197 sub _load_if_possible {
203 log_debug { "Attempt at loading '$class' failed with '$@'" };
209 unshift our @Guess, sub { blessed($_[0]) ? $_[0] : undef };
210 map _load_if_possible($_), qw(
211 Object::Remote::Connector::Local
212 Object::Remote::Connector::LocalSudo
213 Object::Remote::Connector::SSH
214 Object::Remote::Connector::UNIX
219 my ($class, $spec, @args) = @_;
220 foreach my $poss (do { our @Guess }) {
221 if (my $conn = $poss->($spec, @args)) {
230 my ($class, $spec) = @_;
231 return $spec if blessed $spec;
232 my $conn = $class->conn_from_spec($spec);
234 die "Couldn't figure out what to do with ${spec}"
235 unless defined $conn;
237 return $conn->maybe::start::connect;
241 my ($self, @args) = @_;
242 Object::Remote::Handle->new(
243 connection => $self, @args
248 my ($self, $to) = @_;
249 Dlog_debug { "Creating connection to remote node '$to' for connection $_" } $self->_id;
251 $self->send_class_call(0, 'Object::Remote', connect => $to)
256 my ($self, $sub) = @_;
257 my ($pkg, $name) = $sub =~ m/^(.*)::([^:]+)$/;
258 Dlog_debug { "Invoking remote sub '$sub' for connection $_" } $self->_id;
259 return await_future($self->send_class_call(0, $pkg, can => $name));
262 sub send_class_call {
263 my ($self, $ctx, @call) = @_;
264 Dlog_trace { "Sending a class call for connection $_" } $self->_id;
265 $self->send(call => class_call_handler => $ctx => call => @call);
268 sub register_class_call_handler {
270 $self->local_objects_by_id->{'class_call_handler'} ||= do {
271 my $o = $self->new_class_call_handler;
272 $self->_local_object_to_id($o);
277 sub new_class_call_handler {
278 Object::Remote::CodeContainer->new(
280 my ($class, $method) = (shift, shift);
281 use_module($class)->$method(@_);
286 sub register_remote {
287 my ($self, $remote) = @_;
288 Dlog_trace { my $i = $remote->id; "Registered a remote object with id of '$i' for connection $_" } $self->_id;
289 weaken($self->remote_objects_by_id->{$remote->id} = $remote);
294 my ($self, $id) = @_;
295 Dlog_trace { "sending request to free object '$id' for connection $_" } $self->_id;
296 delete $self->remote_objects_by_id->{$id};
297 $self->_send([ free => $id ]);
301 my ($self, $type, @call) = @_;
303 my $future = CPS::Future->new;
304 my $remote = $self->remote_objects_by_id->{$call[0]};
306 unshift @call, $type => $self->_local_object_to_id($future);
308 my $outstanding = $self->outstanding_futures;
309 $outstanding->{$future} = $future;
310 $future->on_ready(sub {
312 delete $outstanding->{$future}
315 $self->_send(\@call);
321 my ($self, $type, @call) = @_;
323 unshift @call, $type => 'NULL';
325 $self->_send(\@call);
329 my ($self, $to_send) = @_;
330 my $fh = $self->send_to_fh;
331 Dlog_trace { "Starting to serialize data in argument to _send for connection $_" } $self->_id;
332 my $serialized = $self->_serialize($to_send)."\n";
333 Dlog_trace { my $l = length($serialized); "serialization is completed; sending '$l' characters of serialized data to $_" } $fh;
336 #TODO this should be converted over to a non-blocking ::WriteChannel class
337 die "filehandle is not open" unless openhandle($fh);
338 log_trace { "file handle has passed openhandle() test; printing to it" };
339 $ret = print $fh $serialized;
340 die "print was not successful: $!" unless defined $ret
344 Dlog_debug { "exception encountered when trying to write to file handle $_: $@" } $fh;
345 my $error = $@; chomp($error);
346 $self->on_close->done("could not write to file handle: $error") unless $self->on_close->is_ready;
354 my ($self, $data) = @_;
355 local our @New_Ids = (-1);
357 my $flat = $self->_encode($self->_deobjectify($data));
360 my $err = $@; # won't get here if the eval doesn't die
361 # don't keep refs to new things
362 delete @{$self->local_objects_by_id}{@New_Ids};
363 die "Error serializing: $err";
367 sub _local_object_to_id {
368 my ($self, $object) = @_;
369 my $id = refaddr($object);
370 $self->local_objects_by_id->{$id} ||= do {
371 push our(@New_Ids), $id if @New_Ids;
378 my ($self, $data) = @_;
379 if (blessed($data)) {
381 $data->isa('Object::Remote::Proxy')
382 and $data->{remote}->connection == $self
384 return +{ __local_object__ => $data->{remote}->id };
386 return +{ __remote_object__ => $self->_local_object_to_id($data) };
388 } elsif (my $ref = ref($data)) {
389 if ($ref eq 'HASH') {
390 my $tied_to = tied(%$data);
391 if(defined($tied_to)) {
392 return +{__remote_tied_hash__ => $self->_local_object_to_id($tied_to)};
394 return +{ map +($_ => $self->_deobjectify($data->{$_})), keys %$data };
396 } elsif ($ref eq 'ARRAY') {
397 my $tied_to = tied(@$data);
398 if (defined($tied_to)) {
399 return +{__remote_tied_array__ => $self->_local_object_to_id($tied_to)};
401 return [ map $self->_deobjectify($_), @$data ];
403 } elsif ($ref eq 'CODE') {
404 my $id = $self->_local_object_to_id(
405 Object::Remote::CodeContainer->new(code => $data)
407 return +{ __remote_code__ => $id };
408 } elsif ($ref eq 'SCALAR') {
409 return +{ __scalar_ref__ => $$data };
410 } elsif ($ref eq 'GLOB') {
411 return +{ __glob_ref__ => $self->_local_object_to_id(
412 Object::Remote::GlobContainer->new(handle => $data)
415 die "Can't collapse reftype $ref";
418 return $data; # plain scalar
422 my ($self, $flat) = @_;
423 Dlog_trace { my $l = length($flat); "Starting to deserialize $l characters of data for connection $_" } $self->_id;
424 my ($type, @rest) = eval { @{$self->_deserialize($flat)} }
425 or do { warn "Deserialize failed for ${flat}: $@"; return };
426 Dlog_trace { "deserialization complete for connection $_" } $self->_id;
427 eval { $self->${\"receive_${type}"}(@rest); 1 }
428 or do { warn "Receive failed for ${flat}: $@"; return };
433 my ($self, $id) = @_;
434 Dlog_trace { "got a receive_free for object '$id' for connection $_" } $self->_id;
435 delete $self->local_objects_by_id->{$id}
436 or warn "Free: no such object $id";
441 my ($self, $future_id, $id, @rest) = @_;
442 Dlog_trace { "got a receive_call for object '$id' for connection $_" } $self->_id;
443 my $future = $self->_id_to_remote_object($future_id);
444 $future->{method} = 'call_discard_free';
445 my $local = $self->local_objects_by_id->{$id}
446 or do { $future->fail("No such object $id"); return };
447 $self->_invoke($future, $local, @rest);
450 sub receive_call_free {
451 my ($self, $future, $id, @rest) = @_;
452 Dlog_trace { "got a receive_call_free for object '$id' for connection $_" } $self->_id;
453 $self->receive_call($future, $id, undef, @rest);
454 $self->receive_free($id);
458 my ($self, $future, $local, $ctx, $method, @args) = @_;
459 Dlog_trace { "got _invoke for a method named '$method' for connection $_" } $self->_id;
460 if ($method =~ /^start::/) {
461 my $f = $local->$method(@args);
462 $f->on_done(sub { undef($f); $future->done(@_) });
464 $f->on_fail(sub { undef($f); $future->fail(@_) });
467 my $do = sub { $local->$method(@args) };
471 ? ($ctx ? $do->() : scalar($do->()))
475 } or do { $future->fail($@); return; };
483 Object::Remote::Connection - An underlying connection for L<Object::Remote>
487 Shipping prioritised over writing this part up. Blame mst.