From: Eric Wong <e@80x24.org>
Date: Sun, 12 Jun 2016 04:46:38 +0000 (+0000)
Subject: view: msg_html uses getline body to reduce latency
X-Git-Tag: v1.0.0~453
X-Git-Url: http://www.git.stargrave.org/?p=public-inbox.git;a=commitdiff_plain;h=31afda256c813443062e0504213d41732e50ee45

view: msg_html uses getline body to reduce latency

We need to ensure we show the message body ASAP since
the thread generation via Xapian could take a while
and maybe even raise an exception or crash.
---

diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index 2057face..534f85ef 100644
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -9,6 +9,7 @@ use warnings;
 use URI::Escape qw/uri_escape_utf8/;
 use Date::Parse qw/str2time/;
 use Encode::MIME::Header;
+use Plack::Util;
 use PublicInbox::Hval qw/ascii_html/;
 use PublicInbox::Linkify;
 use PublicInbox::MID qw/mid_clean id_compress mid2path mid_mime/;
@@ -26,12 +27,26 @@ sub msg_html {
 	my ($ctx, $mime, $footer) = @_;
 	$footer = defined($footer) ? "\n$footer" : '';
 	my $hdr = $mime->header_obj;
-	headers_to_html_header($hdr, $ctx) .
-		multipart_text_as_html($mime, '') .
-		'</pre><hr /><pre>' .
-		html_footer($hdr, 1, $ctx) .
-		'</pre>' . msg_reply($ctx, $hdr) .
-		'<hr /><pre>'.  $footer . '</pre></body></html>';
+	my $n = 0;
+	Plack::Util::inline_object(
+		close => sub {}, # noop
+		getline => sub {
+			my $nr = $n++;
+			if ($nr == 0) {
+				headers_to_html_header($hdr, $ctx) .
+					multipart_text_as_html($mime, '') .
+					'</pre><hr />'
+			} elsif ($nr == 1) {
+				'<pre>' .
+					html_footer($hdr, 1, $ctx) .
+					'</pre>' . msg_reply($ctx, $hdr) .
+					'<hr /><pre>'.  $footer .
+					'</pre></body></html>'
+			} else {
+				undef
+			}
+		}
+	)
 }
 
 # /$INBOX/$MESSAGE_ID/#R
diff --git a/lib/PublicInbox/WWW.pm b/lib/PublicInbox/WWW.pm
index 5fa4e380..c25deff3 100644
--- a/lib/PublicInbox/WWW.pm
+++ b/lib/PublicInbox/WWW.pm
@@ -228,7 +228,7 @@ sub get_mid_html {
 	my $mime = Email::MIME->new($x);
 	searcher($ctx);
 	[ 200, [ 'Content-Type' => 'text/html; charset=UTF-8' ],
-	  [ PublicInbox::View::msg_html($ctx, $mime, $foot) ] ];
+	  PublicInbox::View::msg_html($ctx, $mime, $foot) ];
 }
 
 # /$INBOX/$MESSAGE_ID/t/
diff --git a/t/view.t b/t/view.t
index 3332fb48..6c085991 100644
--- a/t/view.t
+++ b/t/view.t
@@ -9,7 +9,13 @@ use PublicInbox::View;
 sub msg_html ($) {
 	my ($mime) = @_;
 
-	PublicInbox::View::msg_html(undef, $mime);
+	my $s = '';
+	my $body = PublicInbox::View::msg_html(undef, $mime);
+	while (defined(my $buf = $body->getline)) {
+		$s .= $buf;
+	}
+	$body->close;
+	$s;
 }
 
 # plain text