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* [PATCH 0/3] nntpd: updates from imapd
@ 2020-06-16 22:31 Eric Wong
  2020-06-16 22:31 ` [PATCH 1/3] daemon: use ->can to check for IO::Socket::SSL Eric Wong
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Eric Wong @ 2020-06-16 22:31 UTC (permalink / raw)
  To: meta

Since our IMAP code was forked from NNTP and a proving ground
for some new ideas, start bringing the NNTP up-to-date with slow
git storage support and make it less dependent on
IO::Socket::SSL for TLS.

Eric Wong (3):
  daemon: use ->can to check for IO::Socket::SSL
  nntp: event_step: prepare for async git reads
  nntp: support slow blob retrievals

 lib/PublicInbox/DS.pm          |   6 +-
 lib/PublicInbox/HTTP.pm        |   2 +-
 lib/PublicInbox/NNTP.pm        | 150 +++++++++++++++++++--------------
 lib/PublicInbox/NNTPdeflate.pm |  10 +++
 t/nntp.t                       |  12 ++-
 t/nntpd.t                      |  20 ++++-
 6 files changed, 129 insertions(+), 71 deletions(-)

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH 1/3] daemon: use ->can to check for IO::Socket::SSL
  2020-06-16 22:31 [PATCH 0/3] nntpd: updates from imapd Eric Wong
@ 2020-06-16 22:31 ` Eric Wong
  2020-06-16 22:31 ` [PATCH 2/3] nntp: event_step: prepare for async git reads Eric Wong
  2020-06-16 22:31 ` [PATCH 3/3] nntp: support slow blob retrievals Eric Wong
  2 siblings, 0 replies; 4+ messages in thread
From: Eric Wong @ 2020-06-16 22:31 UTC (permalink / raw)
  To: meta

Doing a ref($obj) string comparison ties us to IO::Socket::SSL
(and OpenSSL) In the future, we may support GnuTLS or other TLS
implementations.  This was already done in the IMAP code.
---
 lib/PublicInbox/DS.pm   | 6 +++---
 lib/PublicInbox/HTTP.pm | 2 +-
 lib/PublicInbox/NNTP.pm | 6 +++---
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/lib/PublicInbox/DS.pm b/lib/PublicInbox/DS.pm
index 01c8917eafe..b7753e1a663 100644
--- a/lib/PublicInbox/DS.pm
+++ b/lib/PublicInbox/DS.pm
@@ -415,7 +415,7 @@ sub send_tmpio ($$) {
 }
 
 sub epbit ($$) { # (sock, default)
-    ref($_[0]) eq 'IO::Socket::SSL' ? PublicInbox::TLS::epollbit() : $_[1];
+	$_[0]->can('stop_SSL') ? PublicInbox::TLS::epollbit() : $_[1];
 }
 
 # returns 1 if done, 0 if incomplete
@@ -569,7 +569,7 @@ sub msg_more ($$) {
     my $wbuf = $self->{wbuf};
 
     if (MSG_MORE && (!defined($wbuf) || !scalar(@$wbuf)) &&
-		ref($sock) ne 'IO::Socket::SSL') {
+		!$sock->can('stop_SSL')) {
         my $n = send($sock, $_[1], MSG_MORE);
         if (defined $n) {
             my $nlen = bytes::length($_[1]) - $n;
@@ -619,7 +619,7 @@ sub shutdn_tls_step ($) {
 sub shutdn ($) {
     my ($self) = @_;
     my $sock = $self->{sock} or return;
-    if (ref($sock) eq 'IO::Socket::SSL') {
+    if ($sock->can('stop_SSL')) {
         shutdn_tls_step($self);
     } else {
 	$self->close;
diff --git a/lib/PublicInbox/HTTP.pm b/lib/PublicInbox/HTTP.pm
index b73ce2d7335..6ccf2059240 100644
--- a/lib/PublicInbox/HTTP.pm
+++ b/lib/PublicInbox/HTTP.pm
@@ -59,7 +59,7 @@ sub new ($$$) {
 	my $self = fields::new($class);
 	my $ev = EPOLLIN;
 	my $wbuf;
-	if (ref($sock) eq 'IO::Socket::SSL' && !$sock->accept_SSL) {
+	if ($sock->can('accept_SSL') && !$sock->accept_SSL) {
 		return CORE::close($sock) if $! != EAGAIN;
 		$ev = PublicInbox::TLS::epollbit();
 		$wbuf = [ \&PublicInbox::DS::accept_tls_step ];
diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index bffd773cf9e..be3bddc3f5d 100644
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -47,7 +47,7 @@ sub new ($$$) {
 	my $self = fields::new($class);
 	my $ev = EPOLLIN;
 	my $wbuf;
-	if (ref($sock) eq 'IO::Socket::SSL' && !$sock->accept_SSL) {
+	if ($sock->can('accept_SSL') && !$sock->accept_SSL) {
 		return CORE::close($sock) if $! != EAGAIN;
 		$ev = PublicInbox::TLS::epollbit();
 		$wbuf = [ \&PublicInbox::DS::accept_tls_step, \&greet ];
@@ -97,7 +97,7 @@ sub process_line ($$) {
 sub cmd_capabilities ($;$) {
 	my ($self, undef) = @_;
 	my $res = $CAPABILITIES;
-	if (ref($self->{sock}) ne 'IO::Socket::SSL' &&
+	if (!$self->{sock}->can('accept_SSL') &&
 			$self->{nntpd}->{accept_tls}) {
 		$res .= "STARTTLS\r\n";
 	}
@@ -896,7 +896,7 @@ sub cmd_starttls ($) {
 	my ($self) = @_;
 	my $sock = $self->{sock} or return;
 	# RFC 4642 2.2.1
-	return r502 if (ref($sock) eq 'IO::Socket::SSL' || $self->compressed);
+	return r502 if ($sock->can('accept_SSL') || $self->compressed);
 	my $opt = $self->{nntpd}->{accept_tls} or
 		return '580 can not initiate TLS negotiation';
 	res($self, '382 Continue with TLS negotiation');

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH 2/3] nntp: event_step: prepare for async git reads
  2020-06-16 22:31 [PATCH 0/3] nntpd: updates from imapd Eric Wong
  2020-06-16 22:31 ` [PATCH 1/3] daemon: use ->can to check for IO::Socket::SSL Eric Wong
@ 2020-06-16 22:31 ` Eric Wong
  2020-06-16 22:31 ` [PATCH 3/3] nntp: support slow blob retrievals Eric Wong
  2 siblings, 0 replies; 4+ messages in thread
From: Eric Wong @ 2020-06-16 22:31 UTC (permalink / raw)
  To: meta

This matches PublicInbox::IMAP::event_step and will allow us to
handle blob retrievals from git asynchronously without falling
over on pipelined requests.
---
 lib/PublicInbox/NNTP.pm        | 39 ++++++++++++++++------------------
 lib/PublicInbox/NNTPdeflate.pm | 10 +++++++++
 2 files changed, 28 insertions(+), 21 deletions(-)

diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index be3bddc3f5d..80dd8614fe8 100644
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -956,38 +956,35 @@ sub out ($$;@) {
 sub event_step {
 	my ($self) = @_;
 
-	return unless $self->flush_write && $self->{sock};
+	return unless $self->flush_write && $self->{sock} && !$self->{long_cb};
 
 	$self->update_idle_time;
 	# only read more requests if we've drained the write buffer,
 	# otherwise we can be buffering infinitely w/o backpressure
 
-	my $rbuf = $self->{rbuf} // (\(my $x = ''));
-	my $r = 1;
-
-	if (index($$rbuf, "\n") < 0) {
-		my $off = bytes::length($$rbuf);
-		$r = $self->do_read($rbuf, LINE_MAX, $off) or return;
-	}
-	while ($r > 0 && $$rbuf =~ s/\A[ \t]*([^\n]*?)\r?\n//) {
-		my $line = $1;
-		return $self->close if $line =~ /[[:cntrl:]]/s;
-		my $t0 = now();
-		my $fd = fileno($self->{sock});
-		$r = eval { process_line($self, $line) };
-		my $pending = $self->{wbuf} ? ' pending' : '';
-		out($self, "[$fd] %s - %0.6f$pending", $line, now() - $t0);
-	}
-
+	my $rbuf = $self->{rbuf} // \(my $x = '');
+	my $line = index($$rbuf, "\n");
+	while ($line < 0) {
+		return $self->close if length($$rbuf) >= LINE_MAX;
+		$self->do_read($rbuf, LINE_MAX, length($$rbuf)) or return;
+		$line = index($$rbuf, "\n");
+	}
+	$line = substr($$rbuf, 0, $line + 1, '');
+	$line =~ s/\r?\n\z//s;
+	return $self->close if $line =~ /[[:cntrl:]]/s;
+
+	my $t0 = now();
+	my $fd = fileno($self->{sock});
+	my $r = eval { process_line($self, $line) };
+	my $pending = $self->{wbuf} ? ' pending' : '';
+	out($self, "[$fd] %s - %0.6f$pending", $line, now() - $t0);
 	return $self->close if $r < 0;
-	my $len = bytes::length($$rbuf);
-	return $self->close if ($len >= LINE_MAX);
 	$self->rbuf_idle($rbuf);
 	$self->update_idle_time;
 
 	# maybe there's more pipelined data, or we'll have
 	# to register it for socket-readiness notifications
-	$self->requeue unless $self->{wbuf};
+	$self->requeue unless $pending;
 }
 
 # for graceful shutdown in PublicInbox::Daemon:
diff --git a/lib/PublicInbox/NNTPdeflate.pm b/lib/PublicInbox/NNTPdeflate.pm
index eb400c9c220..dec88aba3a5 100644
--- a/lib/PublicInbox/NNTPdeflate.pm
+++ b/lib/PublicInbox/NNTPdeflate.pm
@@ -71,6 +71,16 @@ sub do_read ($$$$) {
 	$doff = length($dbuf);
 	my $r = PublicInbox::DS::do_read($self, \$dbuf, $len, $doff) or return;
 
+	# Workaround inflate bug appending to OOK scalars:
+	# <https://rt.cpan.org/Ticket/Display.html?id=132734>
+	# We only have $off if the client is pipelining, and pipelining
+	# is where our substr() OOK optimization in event_step makes sense.
+	if ($off) {
+		my $copy = $$rbuf;
+		undef $$rbuf;
+		$$rbuf = $copy;
+	}
+
 	# assert(length($$rbuf) == $off) as far as NNTP.pm is concerned
 	# -ConsumeInput is true, so $dbuf is automatically emptied
 	my $err = $zin->inflate($dbuf, $rbuf);

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH 3/3] nntp: support slow blob retrievals
  2020-06-16 22:31 [PATCH 0/3] nntpd: updates from imapd Eric Wong
  2020-06-16 22:31 ` [PATCH 1/3] daemon: use ->can to check for IO::Socket::SSL Eric Wong
  2020-06-16 22:31 ` [PATCH 2/3] nntp: event_step: prepare for async git reads Eric Wong
@ 2020-06-16 22:31 ` Eric Wong
  2 siblings, 0 replies; 4+ messages in thread
From: Eric Wong @ 2020-06-16 22:31 UTC (permalink / raw)
  To: meta

Having `git cat-file' as a separate process naturally lends
itself to asynchronous dispatch.  Our event loop for -nntpd no
longer blocks on slow git storage.

Pipelining in -imapd was tricky and bugs were exposed by
mbsync(1).  Update t/nntpd.t to support pipelining ARTICLE
requests to ensure we don't have the same problems -imapd
did during development.
---
 lib/PublicInbox/NNTP.pm | 107 +++++++++++++++++++++++++---------------
 t/nntp.t                |  12 +++--
 t/nntpd.t               |  20 +++++++-
 3 files changed, 95 insertions(+), 44 deletions(-)

diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index 80dd8614fe8..6df19f322b6 100644
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -13,6 +13,7 @@ use POSIX qw(strftime);
 use PublicInbox::DS qw(now);
 use Digest::SHA qw(sha1_hex);
 use Time::Local qw(timegm timelocal);
+use PublicInbox::GitAsyncCat;
 use constant {
 	LINE_MAX => 512, # RFC 977 section 2.3
 	r501 => '501 command syntax error',
@@ -408,8 +409,9 @@ sub xref ($$$$) {
 	$ret;
 }
 
-sub set_nntp_headers ($$$$$) {
-	my ($self, $hdr, $ng, $n, $mid) = @_;
+sub set_nntp_headers ($$$) {
+	my ($self, $hdr, $smsg) = @_;
+	my ($mid) = $smsg->{mid};
 
 	# why? leafnode requires a Path: header for some inexplicable
 	# reason.  We'll fake the shortest one possible.
@@ -429,7 +431,8 @@ sub set_nntp_headers ($$$$$) {
 	}
 
 	# clobber some
-	my $xref = xref($self, $ng, $n, $mid);
+	my $ng = $self->{ng};
+	my $xref = xref($self, $ng, $smsg->{num}, $mid);
 	$hdr->header_set('Xref', $xref);
 	$xref =~ s/:[0-9]+//g;
 	$hdr->header_set('Newsgroups', (split(/ /, $xref, 2))[1]);
@@ -441,8 +444,8 @@ sub set_nntp_headers ($$$$$) {
 	}
 }
 
-sub art_lookup ($$$) {
-	my ($self, $art, $set_headers) = @_;
+sub art_lookup ($$) {
+	my ($self, $art) = @_;
 	my $ng = $self->{ng};
 	my ($n, $mid);
 	my $err;
@@ -478,13 +481,7 @@ find_mid:
 	}
 found:
 	my $smsg = $ng->over->get_art($n) or return $err;
-	my $msg = $ng->msg_by_smsg($smsg) or return $err;
-
-	# PublicInbox::Eml->new will modify $msg in-place, so what's
-	# left is the body and we won't need to call ->body(), later
-	my $hdr = PublicInbox::Eml->new($msg)->header_obj;
-	set_nntp_headers($self, $hdr, $ng, $n, $mid) if $set_headers;
-	[ $n, $mid, $msg, $hdr ];
+	$smsg;
 }
 
 sub msg_body_write ($$) {
@@ -495,7 +492,6 @@ sub msg_body_write ($$) {
 	$$msg =~ s/(?<!\r)\n/\r\n/sg; # Alpine barfs without this
 	$$msg .= "\r\n" unless $$msg =~ /\r\n\z/s;
 	$self->msg_more($$msg);
-	'.'
 }
 
 sub set_art {
@@ -504,55 +500,88 @@ sub set_art {
 }
 
 sub msg_hdr_write ($$$) {
-	my ($self, $hdr, $body_follows) = @_;
-	$hdr = $hdr->as_string;
+	my ($self, $eml, $smsg) = @_;
+	set_nntp_headers($self, $eml, $smsg);
+
+	my $hdr = $eml->{hdr} // \(my $x = '');
 	# fixup old bug from import (pre-a0c07cba0e5d8b6a)
-	$hdr =~ s/\A[\r\n]*From [^\r\n]*\r?\n//s;
-	utf8::encode($hdr);
-	$hdr =~ s/(?<!\r)\n/\r\n/sg; # Alpine barfs without this
+	$$hdr =~ s/\A[\r\n]*From [^\r\n]*\r?\n//s;
+	$$hdr =~ s/(?<!\r)\n/\r\n/sg; # Alpine barfs without this
 
 	# for leafnode compatibility, we need to ensure Message-ID headers
 	# are only a single line.
-	$hdr =~ s/^(Message-ID:)[ \t]*\r\n[ \t]+([^\r]+)\r\n/$1 $2\r\n/igsm;
-	$hdr .= "\r\n" if $body_follows;
-	$self->msg_more($hdr);
+	$$hdr =~ s/^(Message-ID:)[ \t]*\r\n[ \t]+([^\r]+)\r\n/$1 $2\r\n/igsm;
+	$self->msg_more($$hdr);
+}
+
+sub blob_cb { # called by git->cat_async via git_async_cat
+	my ($bref, $oid, $type, $size, $smsg) = @_;
+	my $self = $smsg->{nntp};
+	my $code = $smsg->{nntp_code} // 220;
+	if (!defined($oid)) {
+		# it's possible to have TOCTOU if an admin runs
+		# public-inbox-(edit|purge), just move onto the next message
+		return $self->requeue;
+	} elsif ($smsg->{blob} ne $oid) {
+		$self->close;
+		die "BUG: $smsg->{blob} != $oid";
+	}
+	my $r = "$code $smsg->{num} <$smsg->{mid}> article retrieved - ";
+	my $eml = PublicInbox::Eml->new($bref);
+	if ($code == 220) {
+		more($self, $r .= 'head and body follow');
+		msg_hdr_write($self, $eml, $smsg);
+		$self->msg_more("\r\n");
+		msg_body_write($self, $bref);
+	} elsif ($code == 221) {
+		more($self, $r .= 'head follows');
+		msg_hdr_write($self, $eml, $smsg);
+	} elsif ($code == 222) {
+		more($self, $r .= 'body follows');
+		msg_body_write($self, $bref);
+	} else {
+		$self->close;
+		die "BUG: bad code: $r";
+	}
+	$self->write(\".\r\n"); # flushes (includes ->zflush)
+	$self->requeue;
 }
 
 sub cmd_article ($;$) {
 	my ($self, $art) = @_;
-	my $r = art_lookup($self, $art, 1);
-	return $r unless ref $r;
-	my ($n, $mid, $msg, $hdr) = @$r;
+	my $smsg = art_lookup($self, $art);
+	return $smsg unless ref $smsg;
 	set_art($self, $art);
-	more($self, "220 $n <$mid> article retrieved - head and body follow");
-	msg_hdr_write($self, $hdr, 1);
-	msg_body_write($self, $msg);
+	$smsg->{nntp} = $self;
+	git_async_cat($self->{ng}->git, $smsg->{blob}, \&blob_cb, $smsg);
+	undef;
 }
 
 sub cmd_head ($;$) {
 	my ($self, $art) = @_;
-	my $r = art_lookup($self, $art, 2);
-	return $r unless ref $r;
-	my ($n, $mid, undef, $hdr) = @$r;
+	my $smsg = art_lookup($self, $art);
+	return $smsg unless ref $smsg;
 	set_art($self, $art);
-	more($self, "221 $n <$mid> article retrieved - head follows");
-	msg_hdr_write($self, $hdr, 0);
-	'.'
+	$smsg->{nntp} = $self;
+	$smsg->{nntp_code} = 221;
+	git_async_cat($self->{ng}->git, $smsg->{blob}, \&blob_cb, $smsg);
+	undef;
 }
 
 sub cmd_body ($;$) {
 	my ($self, $art) = @_;
-	my $r = art_lookup($self, $art, 0);
-	return $r unless ref $r;
-	my ($n, $mid, $msg) = @$r;
+	my $smsg = art_lookup($self, $art);
+	return $smsg unless ref $smsg;
 	set_art($self, $art);
-	more($self, "222 $n <$mid> article retrieved - body follows");
-	msg_body_write($self, $msg);
+	$smsg->{nntp} = $self;
+	$smsg->{nntp_code} = 222;
+	git_async_cat($self->{ng}->git, $smsg->{blob}, \&blob_cb, $smsg);
+	undef;
 }
 
 sub cmd_stat ($;$) {
 	my ($self, $art) = @_;
-	my $r = art_lookup($self, $art, 0);
+	my $r = art_lookup($self, $art);
 	return $r unless ref $r;
 	my ($n, $mid) = @$r;
 	set_art($self, $art);
diff --git a/t/nntp.t b/t/nntp.t
index 2a9f3a4f6eb..1db896cf46b 100644
--- a/t/nntp.t
+++ b/t/nntp.t
@@ -109,9 +109,12 @@ use_ok 'PublicInbox::Inbox';
 	my $mid = 'a@b';
 	my $mime = PublicInbox::Eml->new("Message-ID: <$mid>\r\n\r\n");
 	my $hdr = $mime->header_obj;
-	my $mock_self = { nntpd => { grouplist => [], 
-				     servername => 'example.com' } };
-	PublicInbox::NNTP::set_nntp_headers($mock_self, $hdr, $ng, 1, $mid);
+	my $mock_self = {
+		nntpd => { grouplist => [], servername => 'example.com' },
+		ng => $ng,
+	};
+	my $smsg = { num => 1, mid => $mid };
+	PublicInbox::NNTP::set_nntp_headers($mock_self, $hdr, $smsg);
 	is_deeply([ $mime->header('Message-ID') ], [ "<$mid>" ],
 		'Message-ID unchanged');
 	is_deeply([ $mime->header('Archived-At') ], [ "<${u}a\@b/>" ],
@@ -126,7 +129,8 @@ use_ok 'PublicInbox::Inbox';
 		'Xref: set');
 
 	$ng->{-base_url} = 'http://mirror.example.com/m/';
-	PublicInbox::NNTP::set_nntp_headers($mock_self, $hdr, $ng, 2, $mid);
+	$smsg->{num} = 2;
+	PublicInbox::NNTP::set_nntp_headers($mock_self, $hdr, $smsg);
 	is_deeply([ $mime->header('Message-ID') ], [ "<$mid>" ],
 		'Message-ID unchanged');
 	is_deeply([ $mime->header('Archived-At') ],
diff --git a/t/nntpd.t b/t/nntpd.t
index b24720eb9dd..c681b01c3d9 100644
--- a/t/nntpd.t
+++ b/t/nntpd.t
@@ -12,6 +12,8 @@ use IO::Socket;
 use Socket qw(IPPROTO_TCP TCP_NODELAY);
 use Net::NNTP;
 use Sys::Hostname;
+use POSIX qw(_exit);
+use Digest::SHA;
 
 # FIXME: make easier to test both versions
 my $version = $ENV{PI_TEST_VERSION} || 1;
@@ -287,21 +289,37 @@ Date: Fri, 02 Oct 1993 00:00:00 +0000
 	# pipelined requests:
 	{
 		my $nreq = 90;
+		my $nart = 2;
 		syswrite($s, "GROUP $group\r\n");
 		my $res = <$s>;
 		my $rdr = fork;
 		if ($rdr == 0) {
-			use POSIX qw(_exit);
 			for (1..$nreq) {
 				<$s> =~ /\A224 / or _exit(1);
 				<$s> =~ /\A1/ or _exit(2);
 				<$s> eq ".\r\n" or _exit(3);
 			}
+			my %sums;
+			for (1..$nart) {
+				<$s> =~ /\A220 / or _exit(4);
+				my $dig = Digest::SHA->new(1);
+				while (my $l = <$s>) {
+					last if $l eq ".\r\n";
+					$dig->add($l);
+				}
+				$dig = $dig->hexdigest;
+				$sums{$dig}++;
+			}
+			if ($nart) {
+				scalar(keys(%sums)) == 1 or _exit(5);
+				(values(%sums))[0] == $nart or _exit(6);
+			}
 			_exit(0);
 		}
 		for (1..$nreq) {
 			syswrite($s, "XOVER 1\r\n");
 		}
+		syswrite($s, "ARTICLE 1\r\n" x $nart);
 		is($rdr, waitpid($rdr, 0), 'reader done');
 		is($? >> 8, 0, 'no errors');
 	}

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, back to index

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-06-16 22:31 [PATCH 0/3] nntpd: updates from imapd Eric Wong
2020-06-16 22:31 ` [PATCH 1/3] daemon: use ->can to check for IO::Socket::SSL Eric Wong
2020-06-16 22:31 ` [PATCH 2/3] nntp: event_step: prepare for async git reads Eric Wong
2020-06-16 22:31 ` [PATCH 3/3] nntp: support slow blob retrievals Eric Wong

unofficial mirror of meta@public-inbox.org

Archives are clonable: git clone --mirror https://yhetil.org/meta

Example config snippet for mirrors

Newsgroups are available over NNTP:
	nntp://news.yhetil.org/yhetil.mail.public-inbox.meta
	nntp://news.public-inbox.org/inbox.mail.public-inbox.meta
	nntp://news.gmane.io/gmane.mail.public-inbox.general


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git