Put the NNTP server name into Xref lines

RFC 5536 sec 3.2.14 says that the server-name in an Xref line is "which
news server generated the header field"; indeed, that is necessary for
newsreaders like gnus to handle references properly.  So pick up the server
name from the config if available (the first name if there's more than
one), from the host name otherwise, and use it rather than the domain
name of the list server.

Tests have been adjusted to match the new behavior.

2 files changed, 12 insertions, 2 deletions

diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index cdbd8e98..cbd4ecf1 100644
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -94,7 +94,7 @@ sub new ($$$) {
         my $self = fields::new($class);
         $self->SUPER::new($sock);
         $self->{nntpd} = $nntpd;
-        res($self, '201 server ready - post via email');
+        res($self, '201 ' . $nntpd->{servername} . ' ready - post via email');
         $self->{rbuf} = '';
         $self->watch_read(1);
         update_idle_time($self);
@@ -410,7 +410,7 @@ sub header_append ($$$) {
 
 sub xref ($$$$) {
         my ($self, $ng, $n, $mid) = @_;
-        my $ret = "$ng->{domain} $ng->{newsgroup}:$n";
+        my $ret = $self->{nntpd}->{servername} . " $ng->{newsgroup}:$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,
diff --git a/lib/PublicInbox/NNTPD.pm b/lib/PublicInbox/NNTPD.pm
index 117c9c03..32848d7c 100644
--- a/lib/PublicInbox/NNTPD.pm
+++ b/lib/PublicInbox/NNTPD.pm
@@ -6,15 +6,25 @@
 package PublicInbox::NNTPD;
 use strict;
 use warnings;
+use Sys::Hostname;
 require PublicInbox::Config;
 
 sub new {
         my ($class) = @_;
+        my $pi_config = PublicInbox::Config->new;
+        my $name = $pi_config->{'publicinbox.nntpserver'};
+        if (!defined($name) or $name eq '') {
+                $name = hostname;
+        } elsif (ref($name) eq 'ARRAY') {
+                $name = $name->[0];
+        }
+
         bless {
                 groups => {},
                 err => \*STDERR,
                 out => \*STDOUT,
                 grouplist => [],
+                servername => $name,
         }, $class;
 }