search: do not index references and inreplyto terms

We no longer need them, as we can rely on index-time thread
resolution and thread merging.  This allows us to index less
data and hopefully increase efficiency.

2 files changed, 2 insertions, 20 deletions

diff --git a/lib/PublicInbox/Search.pm b/lib/PublicInbox/Search.pm
index 4b3830e2..d3faaebb 100644
--- a/lib/PublicInbox/Search.pm
+++ b/lib/PublicInbox/Search.pm
@@ -24,7 +24,8 @@ use constant {
         # 4 - change "Re: " normalization, avoid circular Reference ghosts
         # 5 - subject_path drops trailing '.'
         # 6 - preserve References: order in document data
-        SCHEMA_VERSION => 6,
+        # 7 - remove references and inreplyto terms
+        SCHEMA_VERSION => 7,
         QP_FLAGS => FLAG_PHRASE|FLAG_BOOLEAN|FLAG_LOVEHATE|FLAG_WILDCARD,
 };
 
@@ -37,8 +38,6 @@ my %bool_pfx_internal = (
 my %bool_pfx_external = (
         path => 'XPATH',
         thread => 'G', # newsGroup (or similar entity - e.g. a web forum name)
-        references => 'XREFS',
-        inreplyto => 'XIRT',
 );
 
 my %prob_prefix = (
@@ -87,18 +86,6 @@ sub get_subject_path {
         $self->do_enquire($query, $opts);
 }
 
-# given a message ID, get followups to a message
-sub get_followups {
-        my ($self, $mid, $opts) = @_;
-        $mid = mid_clean($mid);
-        $mid = mid_compress($mid);
-        my $qp = $self->qp;
-        my $irt = $qp->parse_query("inreplyto:$mid", 0);
-        my $ref = $qp->parse_query("references:$mid", 0);
-        my $query = Search::Xapian::Query->new(OP_OR, $irt, $ref);
-        $self->do_enquire($query, $opts);
-}
-
 sub get_thread {
         my ($self, $mid, $opts) = @_;
         my $smsg = eval { $self->lookup_message($mid) };
diff --git a/lib/PublicInbox/SearchIdx.pm b/lib/PublicInbox/SearchIdx.pm
index 2ac53a73..dec33334 100644
--- a/lib/PublicInbox/SearchIdx.pm
+++ b/lib/PublicInbox/SearchIdx.pm
@@ -238,20 +238,15 @@ sub link_message_to_parents {
                 }
         }
         if (@refs) {
-                $doc->add_term(xpfx('inreplyto') . $irt) if defined $irt;
                 $smsg->{references_sorted} = '<'.join('><', @refs).'>';
 
-                my $ref_pfx = xpfx('references');
-
                 # first ref *should* be the thread root,
                 # but we can never trust clients to do the right thing
                 my $ref = shift @refs;
-                $doc->add_term($ref_pfx . $ref);
                 $tid = $self->_resolve_mid_to_tid($ref);
 
                 # the rest of the refs should point to this tid:
                 foreach $ref (@refs) {
-                        $doc->add_term($ref_pfx . $ref);
                         my $ptid = $self->_resolve_mid_to_tid($ref);
                         if ($tid ne $ptid) {
                                 $self->merge_threads($tid, $ptid);