Bug 40853: Add ElasticsearchBoostFieldMatchAmount system preference

This adds a new system preference to control the amount of boost. The default of 0 will act as before this patch.
You can add any positive number, or a number between 0 and 1 for negative boost

To test:
1 - Add a record with
    245 $a novel
2 - Add a record with
    245 $a A novel : $b about things / $c by me
3 - Search for: novel
4 - Search for: a novel
5 - Apply patch, restart all
6 - Repeat searches, note exact titles are boosted
7 - Test with more titles as you are able

Signed-off-by: Jason Robb <jrobb@sekls.org>
Signed-off-by: Thomas Klausner <domm@plix.at>
Signed-off-by: Martin Renvoize <martin.renvoize@openfifth.co.uk>

Koha/SearchEngine/Elasticsearch/QueryBuilder.pm

@@ -392,13 +392,17 @@ sub _build_field_match_boost_query {
     my $indexes  = $params->{indexes};
     my $operands = $params->{operands};
 
+    my $boost_amount = C4::Context->preference('ElasticsearchBoostFieldMatchAmount');
     my @boost_query;
+    my $built_boost;
     my $ea = each_array( @$operands, @$indexes );
     while ( my ( $operand, $index ) = $ea->() ) {
         next unless $operand;
         $index = $index->{field} if ref $index eq 'HASH';
         $index = 'title-cover'   if ( !$index || $index eq 'kw' || $index eq 'ti' || $index eq 'title' );
-        push @boost_query, { match => { $index => { query => $operand } } };
+        $built_boost = { match => { $index => { query => $operand } } };
+        $built_boost->{match}->{$index}->{boost} = $boost_amount if $boost_amount;
+        push @boost_query, $built_boost;
     }
     return \@boost_query;
 }

installer/data/mysql/atomicupdate/bug_40853.pl

@@ -0,0 +1,21 @@
+use Modern::Perl;
+use Koha::Installer::Output qw(say_warning say_success say_info);
+
+return {
+    bug_number  => "40853",
+    description =>
+        "Add ElasticsearchBoostFieldMatchAmount to allow for increasing the weight of the additional field boost search",
+    up => sub {
+        my ($args) = @_;
+        my ( $dbh, $out ) = @$args{qw(dbh out)};
+
+        $dbh->do(
+            q{
+            INSERT IGNORE INTO systempreferences ( `variable`, `value` ) VALUES
+            ('ElasticsearchBoostFieldMatchAmount', '0' )
+        }
+        );
+
+        say $out "Added new system preference 'ElasticsearchBoostFieldMatchAmount'";
+    },
+};

installer/data/mysql/mandatory/sysprefs.sql

@@ -1,3 +1,4 @@
+<<<<<<< HEAD
 INSERT INTO systempreferences ( `variable`, `value` ) VALUES
 ('1PageOrderPDFText', 'Order number must appear on all related correspondence, shipping papers and invoices. Notify us immediately if \n you are unable to supply item(s).'),
 ('AccessControlAllowOrigin', ''),
@@ -240,6 +241,7 @@ INSERT INTO systempreferences ( `variable`, `value` ) VALUES
 ('EdifactLSL', 'ccode'),
 ('EdifactLSQ', 'location'),
 ('ElasticsearchBoostFieldMatch', '0'),
+('ElasticsearchBoostFieldMatchAmount', '0'),
 ('ElasticsearchCrossFields', '1'),
 ('ElasticsearchIndexStatus_authorities', '0'),
 ('ElasticsearchIndexStatus_biblios', '0'),

koha-tmpl/intranet-tmpl/prog/en/modules/admin/preferences/searching.pref

@@ -101,7 +101,9 @@ Searching:
               choices:
                   1: Enable
                   0: Disable
-            - "adding a second 'match' field search to the ES query to boost relevancy. Keyword and title fields will be boosted with title-cover, other fields will boost directly."
+            - "adding a second 'match' field search to the ES query to boost relevancy by"
+            - pref: ElasticsearchBoostFieldMatchAmount
+            - "Keyword and title fields will be boosted with title-cover, other fields will boost directly."
             - "This will not boost CCL style searches, only standard or advanced searches."
         -
             - pref: SavedSearchFilters