2 files changed, 35 insertions, 5 deletions

diff --git a/lib/PublicInbox/GzipFilter.pm b/lib/PublicInbox/GzipFilter.pm
index a7355a8d..115660cb 100644
--- a/lib/PublicInbox/GzipFilter.pm
+++ b/lib/PublicInbox/GzipFilter.pm
@@ -4,7 +4,9 @@
 # Qspawn filter
 package PublicInbox::GzipFilter;
 use strict;
+use parent qw(Exporter);
 use Compress::Raw::Zlib qw(Z_FINISH Z_OK);
+our @EXPORT_OK = qw(gzip_maybe);
 my %OPT = (-WindowBits => 15 + 16, -AppendOutput => 1);
 
 sub new { bless {}, shift }
@@ -16,6 +18,17 @@ sub attach {
         $self
 }
 
+sub gzip_maybe ($) {
+        my ($env) = @_;
+        return if (($env->{HTTP_ACCEPT_ENCODING}) // '') !~ /\bgzip\b/;
+
+        # in case Plack::Middleware::Deflater is loaded:
+        $env->{'plack.skip-deflater'} = 1;
+
+        my ($gz, $err) = Compress::Raw::Zlib::Deflate->new(%OPT);
+        $err == Z_OK ? $gz : undef;
+}
+
 # for GetlineBody (via Qspawn) when NOT using $env->{'pi-httpd.async'}
 sub translate ($$) {
         my $self = $_[0];
diff --git a/lib/PublicInbox/WwwStream.pm b/lib/PublicInbox/WwwStream.pm
index 915a71ba..79ed6871 100644
--- a/lib/PublicInbox/WwwStream.pm
+++ b/lib/PublicInbox/WwwStream.pm
@@ -13,6 +13,8 @@ use base qw(Exporter);
 our @EXPORT_OK = qw(html_oneshot);
 use bytes (); # length
 use PublicInbox::Hval qw(ascii_html prurl);
+use Compress::Raw::Zlib qw(Z_FINISH Z_OK);
+use PublicInbox::GzipFilter qw(gzip_maybe);
 our $TOR_URL = 'https://www.torproject.org/';
 our $CODE_URL = 'https://public-inbox.org/public-inbox.git';
 
@@ -178,13 +180,28 @@ sub html_oneshot ($$;$) {
                 ctx => $ctx,
                 base_url => base_url($ctx),
         }, __PACKAGE__;
-        my @x = (_html_top($self), $sref ? $$sref : (), _html_end($self));
+        my @x;
+        my @h = ('Content-Type' => 'text/html; charset=UTF-8');
+        if (my $gz = gzip_maybe($ctx->{env})) {
+                my $err = $gz->deflate(_html_top($self), $x[0]);
+                die "gzip->deflate: $err" if $err != Z_OK;
+                if ($sref) {
+                        $err = $gz->deflate($sref, $x[0]);
+                        die "gzip->deflate: $err" if $err != Z_OK;
+                }
+                $err = $gz->deflate(_html_end($self), $x[0]);
+                die "gzip->deflate: $err" if $err != Z_OK;
+                $err = $gz->flush($x[0], Z_FINISH);
+                die "gzip->flush: $err" if $err != Z_OK;
+                push @h, qw(Vary Accept-Encoding Content-Encoding gzip);
+        } else {
+                @x = (_html_top($self), $sref ? $$sref : (), _html_end($self));
+        }
+
         my $len = 0;
         $len += bytes::length($_) for @x;
-        [ $code, [
-                'Content-Type' => 'text/html; charset=UTF-8',
-                'Content-Length' => $len
-        ], \@x ];
+        push @h, 'Content-Length', $len;
+        [ $code, \@h, \@x ]
 }
 
 1;