nntp: set Xref across multiple inboxes

Noted by Jonathan Corbet in https://lwn.net/Articles/748184/

diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index e51793505cf515851f7031dc65c982918076f89c..fa890cb2cb274c7d9cb9afb1a461792a03a1fc2e 100644 (file)
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -407,12 +407,30 @@ sub header_append ($$$) {
        $hdr->header_set($k, @v, $v);
 }
 
-sub set_nntp_headers {
-       my ($hdr, $ng, $n, $mid) = @_;
+sub xref ($$$$) {
+       my ($self, $ng, $n, $mid) = @_;
+       my $ret = "$ng->{domain} $ng->{newsgroup}:$n";
+
+       # num_for is pretty cheap and sometimes we'll lookup the existence
+       # of an article without getting even the OVER info.  In other words,
+       # I'm not sure if its worth optimizing by scanning To:/Cc: and
+       # PublicInbox::ExtMsg on the PSGI end is just as expensive
+       foreach my $other (@{$self->{nntpd}->{grouplist}}) {
+               next if $ng eq $other;
+               my $num = eval { $other->mm->num_for($mid) } or next;
+               $ret .= " $other->{newsgroup}:$num";
+       }
+       $ret;
+}
+
+sub set_nntp_headers ($$$$$) {
+       my ($self, $hdr, $ng, $n, $mid) = @_;
 
        # clobber some
-       $hdr->header_set('Newsgroups', $ng->{newsgroup});
-       $hdr->header_set('Xref', xref($ng, $n));
+       my $xref = xref($self, $ng, $n, $mid);
+       $hdr->header_set('Xref', $xref);
+       $xref =~ s/:\d+//g;
+       $hdr->header_set('Newsgroups', (split(/ /, $xref, 2))[1]);
        header_append($hdr, 'List-Post', "<mailto:$ng->{-primary_address}>");
        if (my $url = $ng->base_url) {
                $mid = mid_escape($mid);
@@ -461,7 +479,7 @@ found:
        my $msg = $ng->msg_by_smsg($smsg) or return $err;
        my $s = Email::Simple->new($msg);
        if ($set_headers) {
-               set_nntp_headers($s->header_obj, $ng, $n, $mid);
+               set_nntp_headers($self, $s->header_obj, $ng, $n, $mid);
 
                # must be last
                $s->body_set('') if ($set_headers == 2);
@@ -635,11 +653,6 @@ sub hdr_message_id ($$$) { # optimize XHDR Message-ID [range] for slrnpull.
        }
 }
 
-sub xref ($$) {
-       my ($ng, $n) = @_;
-       "$ng->{domain} $ng->{newsgroup}:$n"
-}
-
 sub mid_lookup ($$) {
        my ($self, $mid) = @_;
        my $self_ng = $self->{ng};
@@ -659,9 +672,11 @@ sub hdr_xref ($$$) { # optimize XHDR Xref [range] for rtin
        my ($self, $xhdr, $range) = @_;
 
        if (defined $range && $range =~ /\A<(.+)>\z/) { # Message-ID
-               my ($ng, $n) = mid_lookup($self, $1);
+               my $mid = $1;
+               my ($ng, $n) = mid_lookup($self, $mid);
                return r430 unless $n;
-               hdr_mid_response($self, $xhdr, $ng, $n, $range, xref($ng, $n));
+               hdr_mid_response($self, $xhdr, $ng, $n, $range,
+                               xref($self, $ng, $n, $mid));
        } else { # numeric range
                $range = $self->{article} unless defined $range;
                my $r = get_range($self, $range);
@@ -674,10 +689,8 @@ sub hdr_xref ($$$) { # optimize XHDR Xref [range] for rtin
                        my $r = $mm->msg_range(\$beg, $end);
                        @$r or return;
                        more($self, join("\r\n", map {
-                               # TODO: use $_->[1] (mid) to fill
-                               # Xref: from other inboxes
                                my $num = $_->[0];
-                               "$num ".xref($ng, $num);
+                               "$num ".xref($self, $ng, $num, $_->[1]);
                        } @$r));
                        1;
                });

diff --git a/t/nntp.t b/t/nntp.t
index 03c7f08361a25fd7107db1be733d565cf7469e4c..57fef48b2169d27d20925d2fa2c55588ec4a478a 100644 (file)
--- a/t/nntp.t
+++ b/t/nntp.t
@@ -109,7 +109,9 @@ use_ok 'PublicInbox::Inbox';
        is($ng->base_url, $u, 'URL expanded');
        my $mid = 'a@b';
        my $mime = Email::MIME->new("Message-ID: <$mid>\r\n\r\n");
-       PublicInbox::NNTP::set_nntp_headers($mime->header_obj, $ng, 1, $mid);
+       my $hdr = $mime->header_obj;
+       my $mock_self = { nntpd => { grouplist => [] } };
+       PublicInbox::NNTP::set_nntp_headers($mock_self, $hdr, $ng, 1, $mid);
        is_deeply([ $mime->header('Message-ID') ], [ "<$mid>" ],
                'Message-ID unchanged');
        is_deeply([ $mime->header('Archived-At') ], [ "<${u}a\@b/>" ],
@@ -124,7 +126,7 @@ use_ok 'PublicInbox::Inbox';
                'Xref: set');
 
        $ng->{-base_url} = 'http://mirror.example.com/m/';
-       PublicInbox::NNTP::set_nntp_headers($mime->header_obj, $ng, 2, $mid);
+       PublicInbox::NNTP::set_nntp_headers($mock_self, $hdr, $ng, 2, $mid);
        is_deeply([ $mime->header('Message-ID') ], [ "<$mid>" ],
                'Message-ID unchanged');
        is_deeply([ $mime->header('Archived-At') ],