www: wire up search to use async xap_helper

The C++ version of xap_helper will allow more complex and
expensive queries.  Both the Perl and C++-only version will
allow offloading search into a separate process which can be
killed via ITIMER_REAL or RLIMIT_CPU in the face of overload.

The xap_helper `mset' command wrapper is simplified to
unconditionally return rank, percentage, and estimated matches
information.  This may slightly penalize mbox retrievals and
lei users, but perhaps that can be a different command entirely.

1 files changed, 4 insertions, 7 deletions

diff --git a/lib/PublicInbox/XapHelper.pm b/lib/PublicInbox/XapHelper.pm
index 27d98ba1..c55a72ce 100644
--- a/lib/PublicInbox/XapHelper.pm
+++ b/lib/PublicInbox/XapHelper.pm
@@ -147,12 +147,8 @@ sub cmd_dump_roots {
 
 sub mset_iter ($$) {
         my ($req, $it) = @_;
-        eval {
-                my $buf = $it->get_docid;
-                $buf .= "\0".$it->get_percent if $req->{p};
-                say { $req->{0} } $buf;
-        };
-        $@ ? iter_retry_check($req) : 0;
+        say { $req->{0} } $it->get_docid, "\0",
+                        $it->get_percent, "\0", $it->get_rank;
 }
 
 sub cmd_mset { # to be used by WWW + IMAP
@@ -165,7 +161,8 @@ sub cmd_mset { # to be used by WWW + IMAP
         $opt->{eidx_key} = $req->{O} if defined $req->{O};
         $opt->{threadid} = $req->{T} if defined $req->{T};
         my $mset = $req->{srch}->mset($qry_str, $opt);
-        say { $req->{0} } 'mset.size=', $mset->size;
+        say { $req->{0} } 'mset.size=', $mset->size,
+                ' .get_matches_estimated=', $mset->get_matches_estimated;
         for my $it ($mset->items) {
                 for (my $t = 10; $t > 0; --$t) {
                         $t = mset_iter($req, $it) // $t;