nntp: improve protocol error messages

NNTP clients (e.g. lei :P) may display the message from the
server, so it's helpful to tell them the article number or
Message-ID that's missing.

diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index 603cf094bf6e96149fcc9909f055099ec809f4d1..1749a7552efa45b84019782dfae742ad0d16e44a 100644 (file)
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -26,8 +26,8 @@ use constant {
        r502 => "502 Command unavailable\r\n",
        r221 => "221 Header follows\r\n",
        r225 => "225 Headers follow (multi-line)\r\n",
-       r430 => "430 No article with that message-id\r\n",
 };
+sub r430 ($) { "430 No article with that message-id <$_[0]>\r\n" }
 use Errno qw(EAGAIN);
 my $ONE_MSGID = qr/\A$MID_EXTRACT\z/;
 my @OVERVIEW = qw(Subject From Date Message-ID References);
@@ -466,17 +466,16 @@ sub set_nntp_headers ($$) {
 
 sub art_lookup ($$$) {
        my ($self, $art, $code) = @_;
-       my ($ibx, $n);
-       my $err;
+       my ($ibx, $n, $mid, $err);
        if (defined $art) {
                if ($art =~ /\A[0-9]+\z/) {
-                       $err = \"423 no such article number in this group\r\n";
+                       $err = \"423 no such article (#$art) in this group\r\n";
                        $n = int($art);
                        goto find_ibx;
                } elsif ($art =~ $ONE_MSGID) {
-                       ($ibx, $n) = mid_lookup($self, $1);
+                       ($ibx, $n) = mid_lookup($self, $mid = $1);
                        goto found if $ibx;
-                       return \r430;
+                       return \r430 $mid;
                } else {
                        return \r501;
                }
@@ -488,7 +487,13 @@ find_ibx:
                        return \"412 no newsgroup has been selected\r\n";
        }
 found:
-       my $smsg = $ibx->over(1)->get_art($n) or return $err;
+       my $smsg = $ibx->over(1)->get_art($n) or do {
+               if (defined $mid) {
+                       warn "BUG: $ibx->{newsgroup} <$mid> #$n missing";
+                       return r430 $mid;
+               }
+               return $err;
+       };
        $smsg->{-ibx} = $ibx;
        if ($code == 223) { # STAT
                set_art($self, $n);
@@ -632,8 +637,8 @@ sub hdr_message_id ($$$) { # optimize XHDR Message-ID [range] for slrnpull.
        my ($self, $xhdr, $range) = @_;
 
        if (defined $range && $range =~ $ONE_MSGID) {
-               my ($ibx, $n) = mid_lookup($self, $1);
-               return r430 unless $n;
+               my ($ibx, $n) = mid_lookup($self, my $mid = $1);
+               return r430 $mid unless $n;
                hdr_mid_response($self, $xhdr, $ibx, $n, $range, $range);
        } else { # numeric range
                $range = $self->{article} unless defined $range;
@@ -703,7 +708,7 @@ sub hdr_xref ($$$) { # optimize XHDR Xref [range] for rtin
        if (defined $range && $range =~ $ONE_MSGID) {
                my $mid = $1;
                my ($ibx, $n) = mid_lookup($self, $mid);
-               return r430 unless $n;
+               return r430 $mid unless defined $n;
                my $smsg = $ibx->over(1)->get_art($n) or return;
                hdr_mid_response($self, $xhdr, $ibx, $n, $range,
                                xref($self, $ibx, $smsg));
@@ -747,8 +752,8 @@ sub smsg_range_i {
 sub hdr_smsg ($$$$) {
        my ($self, $xhdr, $field, $range) = @_;
        if (defined $range && $range =~ $ONE_MSGID) {
-               my ($ibx, $n) = mid_lookup($self, $1);
-               return r430 unless defined $n;
+               my ($ibx, $n) = mid_lookup($self, my $mid = $1);
+               return r430 $mid unless defined $n;
                my $v = over_header_for($ibx, $n, $field);
                hdr_mid_response($self, $xhdr, $ibx, $n, $range, $v);
        } else { # numeric range
@@ -849,9 +854,12 @@ sub over_line ($$$) {
 sub cmd_over ($;$) {
        my ($self, $range) = @_;
        if ($range && $range =~ $ONE_MSGID) {
-               my ($ibx, $n) = mid_lookup($self, $1);
-               defined $n or return r430;
-               my $smsg = $ibx->over(1)->get_art($n) or return r430;
+               my ($ibx, $n) = mid_lookup($self, my $mid = $1);
+               defined $n or return r430 $mid;
+               my $smsg = $ibx->over(1)->get_art($n) or do {
+                       warn "BUG: $ibx->{newsgroup} <$mid> #$n missing";
+                       return r430 $mid;
+               };
                $self->msg_more(
                        "224 Overview information follows (multi-line)\r\n");