preliminary support for io-asyn

[catagits/Catalyst-Runtime.git] / lib / Catalyst / Response.pm

diff --git a/lib/Catalyst/Response.pm b/lib/Catalyst/Response.pm
index 5f49df7..1db5666 100644 (file)
--- a/lib/Catalyst/Response.pm
+++ b/lib/Catalyst/Response.pm
@@ -26,7 +26,27 @@ has _writer => (
     predicate => '_has_writer',
 );
 
-sub DEMOLISH { $_[0]->_writer->close if $_[0]->_has_writer }
+has write_fh => (
+  is=>'ro',
+  predicate=>'has_write_fh',
+  lazy=>1,
+  builder=>'_build_write_fh',
+);
+
+sub _build_write_fh {
+  my $self = shift;
+  $self->_context->finalize_headers unless
+    $self->finalized_headers;
+  $self->_writer;
+};
+
+sub DEMOLISH {
+  my $self = shift;
+  return if $self->has_write_fh;
+  if($self->_has_writer) {
+    $self->_writer->close
+  }
+}
 
 has cookies   => (is => 'rw', default => sub { {} });
 has body      => (is => 'rw', default => undef);
@@ -46,7 +66,6 @@ has headers   => (
 has _context => (
   is => 'rw',
   weak_ref => 1,
-  handles => ['write'],
   clearer => '_clear_context',
 );
 
@@ -54,6 +73,45 @@ sub output { shift->body(@_) }
 
 sub code   { shift->status(@_) }
 
+sub write {
+    my ( $self, $buffer ) = @_;
+
+    # Finalize headers if someone manually writes output
+    $self->_context->finalize_headers unless $self->finalized_headers;
+
+    $buffer = q[] unless defined $buffer;
+
+    my $len = length($buffer);
+    $self->_writer->write($buffer);
+
+    return $len;
+}
+
+sub finalize_headers {
+    my ($self) = @_;
+
+    # This is a less-than-pretty hack to avoid breaking the old
+    # Catalyst::Engine::PSGI. 5.9 Catalyst::Engine sets a response_cb and
+    # expects us to pass headers to it here, whereas Catalyst::Enngine::PSGI
+    # just pulls the headers out of $ctx->response in its run method and never
+    # sets response_cb. So take the lack of a response_cb as a sign that we
+    # don't need to set the headers.
+
+    return unless $self->_has_response_cb;
+
+    # If we already have a writer, we already did this, so don't do it again
+    return if $self->_has_writer;
+
+    my @headers;
+    $self->headers->scan(sub { push @headers, @_ });
+
+    my $writer = $self->_response_cb->([ $self->status, \@headers ]);
+    $self->_set_writer($writer);
+    $self->_clear_response_cb;
+
+    return;
+}
+
 =head1 NAME
 
 Catalyst::Response - stores output responding to the current client request
@@ -208,11 +266,49 @@ $res->code is an alias for this, to match HTTP::Response->code.
 
 Writes $data to the output stream.
 
+=head2 $res->write_fh
+
+Returns a PSGI $writer object that has two methods, write and close.  You can
+close over this object for asynchronous and nonblocking applications.  For
+example (assuming you are using a supporting server, like L<Twiggy>
+
+    package AsyncExample::Controller::Root;
+
+    use Moose;
+
+    BEGIN { extends 'Catalyst::Controller' }
+
+    sub prepare_cb {
+      my $write_fh = pop;
+      return sub {
+        my $message = shift;
+        $write_fh->write("Finishing: $message\n");
+        $write_fh->close;
+      };
+    }
+
+    sub anyevent :Local :Args(0) {
+      my ($self, $c) = @_;
+      my $cb = $self->prepare_cb($c->res->write_fh);
+
+      my $watcher;
+      $watcher = AnyEvent->timer(
+        after => 5,
+        cb => sub {
+          $cb->(scalar localtime);
+          undef $watcher; # cancel circular-ref
+        });
+    }
+
 =head2 $res->print( @data )
 
 Prints @data to the output stream, separated by $,.  This lets you pass
 the response object to functions that want to write to an L<IO::Handle>.
 
+=head2 $self->finalize_headers($c)
+
+Writes headers to response if not already written
+
 =head2 DEMOLISH
 
 Ensures that the response is flushed and closed at the end of the