http: rework async_pass support

Unfortunately, the original design did not work because
middleware can wrap the response body and make `async_pass'
invisible to HTTP.pm

diff --git a/lib/PublicInbox/HTTP.pm b/lib/PublicInbox/HTTP.pm
index 4eb14481fb667d219052f46c5461b974aca2889e..480800bd90b00c51a747bf4cd3a0ff1957ab4f7e 100644 (file)
--- a/lib/PublicInbox/HTTP.pm
+++ b/lib/PublicInbox/HTTP.pm
@@ -11,7 +11,7 @@ package PublicInbox::HTTP;
 use strict;
 use warnings;
 use base qw(Danga::Socket);
-use fields qw(httpd env rbuf input_left remote_addr remote_port);
+use fields qw(httpd env rbuf input_left remote_addr remote_port forward);
 use Fcntl qw(:seek);
 use Plack::HTTPParser qw(parse_http_request); # XS or pure Perl
 use HTTP::Status qw(status_message);
@@ -219,24 +219,6 @@ sub response_write {
                if (ref $body eq 'ARRAY') {
                        $write->($_) foreach @$body;
                        $close->();
-               } elsif ($body->can('async_pass')) { # HTTPD::Async
-                       # prevent us from reading the body faster than we
-                       # can write to the client
-                       my $restart_read = sub { $body->watch_read(1) };
-                       $body->async_pass(sub {
-                               local $/ = \8192;
-                               my $buf = $body->getline;
-                               if (defined $buf) {
-                                       $write->($buf);
-                                       if ($self->{write_buf_size}) {
-                                               $body->watch_read(0);
-                                               $self->write($restart_read);
-                                       }
-                                       return; # continue waiting
-                               }
-                               $body->close;
-                               $close->();
-                       });
                } else {
                        my $pull;
                        $pull = sub {
@@ -438,7 +420,9 @@ sub event_err { $_[0]->close }
 
 sub close {
        my $self = shift;
-       $self->{env} = undef;
+       my $forward = $self->{forward};
+       $forward->close if $forward;
+       $self->{forward} = $self->{env} = undef;
        $self->SUPER::close(@_);
 }
 

diff --git a/lib/PublicInbox/HTTPD/Async.pm b/lib/PublicInbox/HTTPD/Async.pm
index 8f3a6a0907c72d00aadcb69b09a651197032dd31..8efa7a668ff027b02e78a1d9173487efb94e8423 100644 (file)
--- a/lib/PublicInbox/HTTPD/Async.pm
+++ b/lib/PublicInbox/HTTPD/Async.pm
@@ -21,29 +21,38 @@ sub new {
        $self;
 }
 
-sub async_pass { $_[0]->{cb} = $_[1] }
-sub event_read { $_[0]->{cb}->() }
-sub event_hup { $_[0]->{cb}->() }
-sub event_err { $_[0]->{cb}->() }
-sub sysread { shift->{sock}->sysread(@_) }
-
-sub getline {
-       my ($self) = @_;
-       die 'getline called without $/ ref' unless ref $/;
-       while (1) {
-               my $ret = $self->read(8192); # Danga::Socket::read
-               return $$ret if defined $ret;
+sub async_pass {
+       my ($self, $io, $fh) = @_;
+       my $restart_read = sub { $self->watch_read(1) };
 
-               return unless $!{EAGAIN} || $!{EINTR};
+       # In case the client HTTP connection ($io) dies, it
+       # will automatically close this ($self) object.
+       $io->{forward} = $self;
+       $self->{cb} = sub {
+               my $r = sysread($self->{sock}, my $buf, 8192);
+               if ($r) {
+                       $fh->write($buf);
+                       if ($io->{write_buf_size}) {
+                               $self->watch_read(0);
+                               $io->write($restart_read);
+                       }
+                       return; # stay in watch_read
+               } elsif (!defined $r) {
+                       return if $!{EAGAIN} || $!{EINTR};
+               }
 
-               # in case of spurious wakeup, hopefully we never hit this
-               my $vin = '';
-               vec($vin, $self->{fd}, 1) = 1;
-               my $n;
-               do { $n = select($vin, undef, undef, undef) } until $n;
+               # Done! Error handling will happen in $fh->close
+               $io->{forward} = undef;
+               $self->close;
+               $fh->close;
        }
 }
 
+sub event_read { $_[0]->{cb}->() }
+sub event_hup { $_[0]->{cb}->() }
+sub event_err { $_[0]->{cb}->() }
+sub sysread { shift->{sock}->sysread(@_) }
+
 sub close {
        my $self = shift;
        $self->{cb} = undef;