add non-blocking file handle support for reading in miniloop and change miniloop...

[scpubgit/Object-Remote.git] / lib / Object / Remote / Role / Connector / PerlInterpreter.pm

diff --git a/lib/Object/Remote/Role/Connector/PerlInterpreter.pm b/lib/Object/Remote/Role/Connector/PerlInterpreter.pm
index b8e3f75..291a664 100644 (file)
--- a/lib/Object/Remote/Role/Connector/PerlInterpreter.pm
+++ b/lib/Object/Remote/Role/Connector/PerlInterpreter.pm
@@ -1,6 +1,7 @@
 package Object::Remote::Role::Connector::PerlInterpreter;
 
 use IPC::Open2;
+use IPC::Open3; 
 use IO::Handle;
 use Object::Remote::ModuleSender;
 use Object::Remote::Handle;
@@ -12,6 +13,9 @@ use Moo::Role;
 with 'Object::Remote::Role::Connector';
 
 has module_sender => (is => 'lazy');
+#if no child_stderr file handle is specified then stderr
+#of the child will be connected to stderr of the parent
+has stderr => ( is => 'rw', default => sub { \*STDERR } );
 
 sub _build_module_sender {
   my ($hook) =
@@ -27,6 +31,7 @@ has perl_command => (is => 'lazy');
 #ulimit of ~500 megs of v-ram
 #TODO only works with ssh with quotes but only works locally
 #with out quotes
+#sub _build_perl_command { [ 'sh', '-c', '"ulimit -v 80000; nice -n 15 perl -"' ] }
 sub _build_perl_command { [ 'sh', '-c', '"ulimit -v 500000; nice -n 15 perl -"' ] }
 #sub _build_perl_command { [ 'perl', '-' ] }
 
@@ -54,18 +59,78 @@ sub final_perl_command { shift->perl_command }
 
 sub _start_perl {
   my $self = shift;
+  my $given_stderr = $self->stderr;
+  my $foreign_stderr;
+ 
   Dlog_debug { "invoking connection to perl interpreter using command line: $_" } @{$self->final_perl_command};
-  my $pid = open2(
-    my $foreign_stdout,
+  
+  use Symbol; 
+  
+  if (defined($given_stderr)) {
+      $foreign_stderr = gensym();
+  } else {
+      $foreign_stderr = ">&STDERR";
+  }
+  
+  my $pid = open3(
     my $foreign_stdin,
+    my $foreign_stdout,
+    $foreign_stderr,
     @{$self->final_perl_command},
   ) or die "Failed to run perl at '$_[0]': $!";
+  
+  if (defined($given_stderr)) {   
+      log_warn { "using experimental cat for child stderr" };
+        
+      #TODO refactor if this solves the problem
+      Object::Remote->current_loop
+                    ->watch_io(
+                        handle => $foreign_stderr,
+                        on_read_ready => sub {
+                          my $buf = ''; 
+                          my $len = sysread($foreign_stderr, $buf, 32768);
+                          if (!defined($len) or $len == 0) {
+                            log_trace { "Got EOF or error on child stderr, removing from watcher" };
+                            $self->stderr(undef);
+                            Object::Remote->current_loop
+                                          ->unwatch_io(
+                                              handle => $foreign_stderr,
+                                              on_read_ready => 1
+                                            );
+                          } else {
+                              Dlog_trace { "got $len characters of stderr data for connection" };
+                              print $given_stderr $buf or die "could not send stderr data: $!";
+                          }
+                         }
+                      );     
+  }
+      
+  #TODO open2() dupes the child stderr into the calling
+  #process stderr which means if this process exits the
+  #child is still attached to the shell - using open3()
+  #and having the run loop manage the stderr means this
+  #won't happen BUT if the run loop just sends the remote
+  #stderr data to the local stderr the logs will interleave
+  #for sure - a simple test would be to use open3() and just
+  #close the remote stderr and see what happens - a longer
+  #term solution would be for Object::Remote to offer a feature
+  #where the user of a connection species a destination for output
+  #either a file name or their own file handle and the node output
+  #is dumped to it 
+#  my $pid = open2(
+#    my $foreign_stdout,
+#    my $foreign_stdin,
+#    @{$self->final_perl_command},
+#  ) or die "Failed to run perl at '$_[0]': $!";
+
   Dlog_trace { "Connection to remote side successful; remote stdin and stdout: $_" } [ $foreign_stdin, $foreign_stdout ];
   return ($foreign_stdin, $foreign_stdout, $pid);
 }
 
 #TODO open2() forks off a child and I have not been able to locate
 #a mechanism for reaping dead children so they don't become zombies
+#CONFIRMED there is no reaping of children being done, find a safe
+#way to do it
 sub _open2_for {
   my $self = shift;
   my ($foreign_stdin, $foreign_stdout, $pid) = $self->_start_perl(@_);