qspawn|getlinebody: support streaming filters

[public-inbox.git] / lib / PublicInbox / Qspawn.pm

diff --git a/lib/PublicInbox/Qspawn.pm b/lib/PublicInbox/Qspawn.pm
index b80dac1f3ca5bf829bfc3c04613a89155dc0c809..3247cd078cba71aaaa058798cff4840309ca7932 100644 (file)
--- a/lib/PublicInbox/Qspawn.pm
+++ b/lib/PublicInbox/Qspawn.pm
@@ -9,6 +9,7 @@ package PublicInbox::Qspawn;
 use strict;
 use warnings;
 use PublicInbox::Spawn qw(popen_rd);
+require Plack::Util;
 my $def_limiter;
 
 sub new ($$$;) {
@@ -60,11 +61,25 @@ sub start {
        }
 }
 
+# create a filter for "push"-based streaming PSGI writes used by HTTPD::Async
+sub filter_fh ($$) {
+       my ($fh, $filter) = @_;
+       Plack::Util::inline_object(
+               close => sub {
+                       $fh->write($filter->(undef));
+                       $fh->close;
+               },
+               write => sub {
+                       $fh->write($filter->($_[0]));
+               });
+}
+
 sub psgi_return {
        my ($self, $env, $limiter, $parse_hdr) = @_;
        my ($fh, $rpipe);
        my $end = sub {
-               if (my $err = $self->finish) {
+               my $err = $self->finish;
+               if ($err && !$env->{'qspawn.quiet'}) {
                        $err = join(' ', @{$self->{args}->[0]}).": $err\n";
                        $env->{'psgi.errors'}->print($err);
                }
@@ -84,6 +99,7 @@ sub psgi_return {
        my $cb = sub {
                my $r = $rd_hdr->() or return;
                $rd_hdr = undef;
+               my $filter = delete $env->{'qspawn.filter'};
                if (scalar(@$r) == 3) { # error
                        if ($async) {
                                $async->close; # calls rpipe->close
@@ -94,11 +110,12 @@ sub psgi_return {
                        $res->($r);
                } elsif ($async) {
                        $fh = $res->($r); # scalar @$r == 2
+                       $fh = filter_fh($fh, $filter) if $filter;
                        $async->async_pass($env->{'psgix.io'}, $fh, \$buf);
                } else { # for synchronous PSGI servers
                        require PublicInbox::GetlineBody;
                        $r->[2] = PublicInbox::GetlineBody->new($rpipe, $end,
-                                                               $buf);
+                                                               $buf, $filter);
                        $res->($r);
                }
        };