X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=scpubgit%2FObject-Remote.git;a=blobdiff_plain;f=lib%2FObject%2FRemote%2FConnection.pm;h=bb1b2603c67a16e1c749ec9e25152d48d5d57981;hp=d338a21b6b4bcb8ad9bb4add3782a26a4eec351f;hb=bef36e73e4257b2ba8e59eb55661ffc51d8a620a;hpb=6b7b2732b7cc6b6c626469f2e6300b7012caef07

diff --git a/lib/Object/Remote/Connection.pm b/lib/Object/Remote/Connection.pm
index d338a21..bb1b260 100644
--- a/lib/Object/Remote/Connection.pm
+++ b/lib/Object/Remote/Connection.pm
@@ -1,33 +1,45 @@
 package Object::Remote::Connection;
 
+use Object::Remote::Logging qw (:log :dlog router);
 use Object::Remote::Future;
 use Object::Remote::Null;
 use Object::Remote::Handle;
 use Object::Remote::CodeContainer;
 use Object::Remote::GlobProxy;
 use Object::Remote::GlobContainer;
-use Object::Remote::Logging qw (:log :dlog);
+use Object::Remote::Tied;
 use Object::Remote;
 use Symbol;
 use IO::Handle;
+use POSIX ":sys_wait_h";
 use Module::Runtime qw(use_module);
-use Scalar::Util qw(weaken blessed refaddr);
+use Scalar::Util qw(weaken blessed refaddr openhandle);
 use JSON::PP qw(encode_json);
+use Future;
+use Carp qw(croak);
 use Moo;
 
-our $DEBUG = !!$ENV{OBJECT_REMOTE_DEBUG};
-#numbering each connection allows it to be
-#tracked along with file handles in
-#the logs
-BEGIN { our $NEXT_CONNECTION_ID = 0 }
+BEGIN { router()->exclude_forwarding }
+
+END {
+  our %child_pids;
+
+  log_trace { "END handler is being invoked in " . __PACKAGE__ };
+
+  foreach(keys(%child_pids)) {
+    log_debug { "Killing child process '$_'" };
+    kill('TERM', $_);
+  }
+}
+
 has _id => ( is => 'ro', required => 1, default => sub { our $NEXT_CONNECTION_ID++ } );
 
 has send_to_fh => (
   is => 'ro', required => 1,
   trigger => sub {
-      my $self = $_[0];
-      $_[1]->autoflush(1);
-      Dlog_trace { my $id = $self->_id; "connection had send_to_fh set to $_"  } $_[1];
+    my $self = $_[0];
+    $_[1]->autoflush(1);
+    Dlog_trace { my $id = $self->_id; "connection had send_to_fh set to $_"  } $_[1];
   },
 );
 
@@ -35,23 +47,23 @@ has read_channel => (
   is => 'ro', required => 1,
   trigger => sub {
     my ($self, $ch) = @_;
-    Dlog_trace { my $id = $self->_id; "trigger for read_channel has been invoked for connection $id; file handle is " } $ch->fh; 
+    my $id = $self->_id;
+    Dlog_trace { "trigger for read_channel has been invoked for connection $id; file handle is $_" } $ch->fh;
     weaken($self);
     $ch->on_line_call(sub { $self->_receive(@_) });
-    $ch->on_close_call(sub { $self->on_close->done(@_) });
+    $ch->on_close_call(sub {
+      log_trace { "invoking 'done' on on_close handler for connection id '$id'" };
+      $self->on_close->done(@_);
+    });
   },
 );
 
 has on_close => (
-  is => 'ro', default => sub { CPS::Future->new },
+  is => 'rw', default => sub { $_[0]->_install_future_handlers(Future->new) },
   trigger => sub {
-    my ($self, $f) = @_;
-    Dlog_trace { "trigger for on_close has been invoked for connection $_" } $self->_id;
-    weaken($self);
-    $f->on_done(sub {
-      $self->_fail_outstanding("Connection lost: ".($f->get)[0]);
-    });
-  }
+    log_trace { "Installing handlers into future via trigger" };
+    $_[0]->_install_future_handlers($_[1])
+  },
 );
 
 has child_pid => (is => 'ro');
@@ -68,15 +80,6 @@ has remote_objects_by_id => (
 
 has outstanding_futures => (is => 'ro', default => sub { {} });
 
-sub _fail_outstanding {
-  my ($self, $error) = @_;
-  Dlog_debug { "Failing outstanding futures with '$error' for connection $_" } $self->_id;
-  my $outstanding = $self->outstanding_futures;
-  $_->fail($error) for values %$outstanding;
-  %$outstanding = ();
-  return;
-}
-
 has _json => (
   is => 'lazy',
   handles => {
@@ -85,6 +88,82 @@ has _json => (
   },
 );
 
+after BUILD => sub {
+  my ($self) = @_;
+  my $pid = $self->child_pid;
+  our %child_pids;
+  return unless defined $pid;
+  $child_pids{$pid} = 1;
+  return;
+};
+
+sub BUILD { }
+
+sub is_valid {
+  my ($self) = @_;
+  my $valid = ! $self->on_close->is_ready;
+
+  log_trace {
+    my $id = $self->_id;
+    my $text;
+    if ($valid) {
+      $text = 'yes';
+    } else {
+      $text = 'no';
+    }
+    "Connection '$id' is valid: '$text'"
+  };
+
+  return $valid;
+}
+
+sub _fail_outstanding {
+  my ($self, $error) = @_;
+  my $outstanding = $self->outstanding_futures;
+
+  Dlog_debug {
+    sprintf "Failing %i outstanding futures with '$error'", scalar(keys(%$outstanding))
+  };
+
+  foreach(keys(%$outstanding)) {
+    log_trace { "Failing future for $_" };
+    my $future = $outstanding->{$_};
+    $future->fail("$error\n");
+  }
+
+  %$outstanding = ();
+  return;
+}
+
+sub _install_future_handlers {
+    my ($self, $f) = @_;
+    our %child_pids;
+    Dlog_trace { "Installing handlers into future for connection $_" } $self->_id;
+    weaken($self);
+    $f->on_done(sub {
+      my $pid = $self->child_pid;
+      Dlog_trace { "Executing on_done handler in future for connection $_" } $self->_id;
+      $self->_fail_outstanding("Object::Remote connection lost: " . ($f->get)[0]);
+      return unless defined $pid;
+      log_debug { "Waiting for child '$pid' to exit" };
+      my $ret = waitpid($pid, 0);
+      if ($ret != $pid) {
+        log_debug { "Waited for pid $pid but waitpid() returned $ret" };
+        return;
+      } elsif ($? & 127) {
+          log_warn { "Remote interpreter did not exit cleanly" };
+      } else {
+        log_verbose {
+          my $exit_value = $? >> 8;
+          "Remote Perl interpreter exited with value '$exit_value'"
+        };
+      }
+
+      delete $child_pids{$pid};
+    });
+    return $f;
+};
+
 sub _id_to_remote_object {
   my ($self, $id) = @_;
   Dlog_trace { "fetching proxy for remote object with id '$id' for connection $_" } $self->_id;
@@ -122,28 +201,63 @@ sub _build__json {
     __local_object__ => sub {
       $self->local_objects_by_id->{$_[0]}
     }
+  )->filter_json_single_key_object(
+    __remote_tied_hash__ => sub {
+      my %tied_hash;
+      tie %tied_hash, 'Object::Remote::Tied', $self->_id_to_remote_object(@_);
+      return \%tied_hash;
+    }
+  )->filter_json_single_key_object(
+    __remote_tied_array__ => sub {
+      my @tied_array;
+      tie @tied_array, 'Object::Remote::Tied', $self->_id_to_remote_object(@_);
+      return \@tied_array;
+    }
   );
 }
 
+sub _load_if_possible {
+  my ($class) = @_;
+
+  use_module($class);
+
+  if ($@) {
+    log_debug { "Attempt at loading '$class' failed with '$@'" };
+  }
+
+}
+
 BEGIN {
   unshift our @Guess, sub { blessed($_[0]) ? $_[0] : undef };
-  eval { require Object::Remote::Connector::Local };
-  eval { require Object::Remote::Connector::LocalSudo };
-  eval { require Object::Remote::Connector::SSH };
-  eval { require Object::Remote::Connector::UNIX };
+  map _load_if_possible($_), qw(
+    Object::Remote::Connector::Local
+    Object::Remote::Connector::LocalSudo
+    Object::Remote::Connector::SSH
+    Object::Remote::Connector::UNIX
+    Object::Remote::Connector::INET
+  );
 }
 
-sub new_from_spec {
-  my ($class, $spec) = @_;
-  return $spec if blessed $spec;
-  Dlog_debug { "creating a new connection from spec" };
+sub conn_from_spec {
+  my ($class, $spec, @args) = @_;
   foreach my $poss (do { our @Guess }) {
-    if (my $conn = $poss->($spec)) {
-      #Dlog_debug { my $id = $conn->_id; "created connection $id for spec $_" } $spec;
-      return $conn->maybe::start::connect;
+    if (my $conn = $poss->($spec, @args)) {
+      return $conn;
     }
   }
-  die "Couldn't figure out what to do with ${spec}";
+
+  return undef;
+}
+
+sub new_from_spec {
+  my ($class, $spec, @args) = @_;
+  return $spec if blessed $spec;
+  my $conn = $class->conn_from_spec($spec, @args);
+
+  die "Couldn't figure out what to do with ${spec}"
+    unless defined $conn;
+
+  return $conn->maybe::start::connect;
 }
 
 sub remote_object {
@@ -164,7 +278,7 @@ sub connect {
 sub remote_sub {
   my ($self, $sub) = @_;
   my ($pkg, $name) = $sub =~ m/^(.*)::([^:]+)$/;
-  Dlog_debug { "Invoking remote sub '$sub' for connection $_" } $self->_id;
+  Dlog_debug { "Invoking remote sub '$sub' for connection '$_'" } $self->_id;
   return await_future($self->send_class_call(0, $pkg, can => $name));
 }
 
@@ -201,7 +315,10 @@ sub register_remote {
 
 sub send_free {
   my ($self, $id) = @_;
-  Dlog_debug { "sending request to free object '$id' for connection $_" } $self->_id;
+  Dlog_trace { "sending request to free object '$id' for connection $_" } $self->_id;
+  #TODO this shows up some times when a remote side dies in the middle of a remote
+  #method invocation - possibly only when the object is being constructed?
+  #(in cleanup) Use of uninitialized value $id in delete at ../Object-Remote/lib/Object/Remote/Connection.
   delete $self->remote_objects_by_id->{$id};
   $self->_send([ free => $id ]);
 }
@@ -209,7 +326,7 @@ sub send_free {
 sub send {
   my ($self, $type, @call) = @_;
 
-  my $future = CPS::Future->new;
+  my $future = Future->new;
   my $remote = $self->remote_objects_by_id->{$call[0]};
 
   unshift @call, $type => $self->_local_object_to_id($future);
@@ -237,16 +354,32 @@ sub send_discard {
 sub _send {
   my ($self, $to_send) = @_;
   my $fh = $self->send_to_fh;
+
+  unless ($self->is_valid) {
+    croak "Attempt to invoke _send on a connection that is not valid";
+  }
+
   Dlog_trace { "Starting to serialize data in argument to _send for connection $_" } $self->_id;
   my $serialized = $self->_serialize($to_send)."\n";
   Dlog_trace { my $l = length($serialized); "serialization is completed; sending '$l' characters of serialized data to $_" } $fh;
-  #TODO this is very risky for deadlocks unless it's set to non-blocking and then with out extra
-  #logic it could easily do short-writes to the remote side
-  my $ret = print $fh $serialized;
-  Dlog_trace { my $r = defined $ret ? $ret : 'undef'; "print() returned $r with $_" } $fh;
-  #TODO hrm reason print's return value was ignored?
-  die "could not write to filehandle: $!" unless $ret;
-  return $ret; 
+  my $ret;
+  eval {
+    #TODO this should be converted over to a non-blocking ::WriteChannel class
+    die "filehandle is not open" unless openhandle($fh);
+    log_trace { "file handle has passed openhandle() test; printing to it" };
+    $ret = print $fh $serialized;
+    die "print was not successful: $!" unless defined $ret
+  };
+
+  if ($@) {
+    Dlog_debug { "exception encountered when trying to write to file handle $_: $@" } $fh;
+    my $error = $@;
+    chomp($error);
+    $self->on_close->done("could not write to file handle: $error") unless $self->on_close->is_ready;
+    return;
+  }
+
+  return $ret;
 }
 
 sub _serialize {
@@ -254,7 +387,6 @@ sub _serialize {
   local our @New_Ids = (-1);
   return eval {
     my $flat = $self->_encode($self->_deobjectify($data));
-    warn "$$ >>> ${flat}\n" if $DEBUG;
     $flat;
   } || do {
     my $err = $@; # won't get here if the eval doesn't die
@@ -287,9 +419,19 @@ sub _deobjectify {
     }
   } elsif (my $ref = ref($data)) {
     if ($ref eq 'HASH') {
-      return +{ map +($_ => $self->_deobjectify($data->{$_})), keys %$data };
+      my $tied_to = tied(%$data);
+      if(defined($tied_to)) {
+        return +{__remote_tied_hash__ => $self->_local_object_to_id($tied_to)};
+      } else {
+        return +{ map +($_ => $self->_deobjectify($data->{$_})), keys %$data };
+      }
     } elsif ($ref eq 'ARRAY') {
-      return [ map $self->_deobjectify($_), @$data ];
+      my $tied_to = tied(@$data);
+      if (defined($tied_to)) {
+        return +{__remote_tied_array__ => $self->_local_object_to_id($tied_to)};
+      } else {
+        return [ map $self->_deobjectify($_), @$data ];
+      }
     } elsif ($ref eq 'CODE') {
       my $id = $self->_local_object_to_id(
                  Object::Remote::CodeContainer->new(code => $data)
@@ -310,7 +452,6 @@ sub _deobjectify {
 
 sub _receive {
   my ($self, $flat) = @_;
-  warn "$$ <<< $flat\n" if $DEBUG;
   Dlog_trace { my $l = length($flat); "Starting to deserialize $l characters of data for connection $_" } $self->_id;
   my ($type, @rest) = eval { @{$self->_deserialize($flat)} }
     or do { warn "Deserialize failed for ${flat}: $@"; return };
@@ -373,8 +514,28 @@ sub _invoke {
 
 Object::Remote::Connection - An underlying connection for L<Object::Remote>
 
-=head1 LAME
+  use Object::Remote;
+
+  my $local = Object::Remote->connect('-');
+  my $remote = Object::Remote->connect('myserver');
+  my $remote_user = Object::Remote->connect('user@myserver');
+  my $local_sudo = Object::Remote->connect('user@');
+
+  #$remote can be any other connection object
+  my $hostname = Sys::Hostname->can::on($remote, 'hostname');
+
+=head1 DESCRIPTION
+
+This is the class that supports connections to remote objects.
+
+=head1 SEE ALSO
+
+=over 4
+
+=item C<Object::Remote::Role::Connector::PerlInterpreter>
+
+=item C<Object::Remote>
 
-Shipping prioritised over writing this part up. Blame mst.
+=back
 
 =cut