view: make /$INBOX/$MSGID/ permalink async

This will allow -httpd to handle other requusts if waiting on
an HDD seek or git to decode a blob.

1 files changed, 35 insertions, 5 deletions

diff --git a/lib/PublicInbox/WwwStream.pm b/lib/PublicInbox/WwwStream.pm
index 42fb183f..eecc2701 100644
--- a/lib/PublicInbox/WwwStream.pm
+++ b/lib/PublicInbox/WwwStream.pm
@@ -15,9 +15,6 @@ use PublicInbox::Hval qw(ascii_html prurl);
 our $TOR_URL = 'https://www.torproject.org/';
 our $CODE_URL = 'https://public-inbox.org/public-inbox.git';
 
-# noop for HTTP.pm (and any other PSGI servers)
-sub close {}
-
 sub base_url ($) {
         my $ctx = shift;
         my $base_url = $ctx->{-inbox}->base_url($ctx->{env});
@@ -40,6 +37,11 @@ sub response {
         [ $code, $res_hdr, $ctx ]
 }
 
+sub async_eml { # ->{async_eml} for async_blob_cb
+        my ($ctx, $eml) = @_;
+        $ctx->{http_out}->write($ctx->translate($ctx->{cb}->($ctx, $eml)));
+}
+
 sub html_top ($) {
         my ($ctx) = @_;
         my $ibx = $ctx->{-inbox};
@@ -157,8 +159,14 @@ EOF
 sub getline {
         my ($ctx) = @_;
         my $cb = $ctx->{cb} or return;
-        if (defined(my $buf = $cb->($ctx))) {
-                return $ctx->translate($buf);
+        while (defined(my $x = $cb->($ctx))) { # x = smsg or scalar non-ref
+                if (ref($x)) { # smsg
+                        my $eml = $ctx->{-inbox}->smsg_eml($x) or next;
+                        $ctx->{smsg} = $x;
+                        return $ctx->translate($cb->($ctx, $eml));
+                } else { # scalar
+                        return $ctx->translate($x);
+                }
         }
         delete $ctx->{cb};
         $ctx->zflush(_html_end($ctx));
@@ -179,4 +187,26 @@ sub html_oneshot ($$;$) {
         [ $code, $res_hdr, \@bdy ]
 }
 
+sub async_next ($) {
+        my ($http) = @_; # PublicInbox::HTTP
+        my $ctx = $http->{forward} or return;
+        eval {
+                if (my $smsg = $ctx->{smsg} = $ctx->{cb}->($ctx)) {
+                        $ctx->smsg_blob($smsg);
+                } else {
+                        $ctx->{http_out}->write(
+                                        $ctx->translate(_html_end($ctx)));
+                        $ctx->close; # GzipFilter->close
+                }
+        };
+        warn "E: $@" if $@;
+}
+
+sub aresponse {
+        my ($ctx, $code, $cb) = @_;
+        my $res_hdr = [ 'Content-Type' => 'text/html; charset=UTF-8' ];
+        init($ctx, $cb);
+        $ctx->psgi_response($code, $res_hdr, \&async_next, \&async_eml);
+}
+
 1;