1 package Koha::SearchEngine::Elasticsearch::QueryBuilder;
3 # This file is part of Koha.
5 # Copyright 2014 Catalyst IT Ltd.
7 # Koha is free software; you can redistribute it and/or modify it
8 # under the terms of the GNU General Public License as published by
9 # the Free Software Foundation; either version 3 of the License, or
10 # (at your option) any later version.
12 # Koha is distributed in the hope that it will be useful, but
13 # WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with Koha; if not, see <http://www.gnu.org/licenses>.
22 Koha::SearchEngine::Elasticsearch::QueryBuilder - constructs elasticsearch
23 query objects from user-supplied queries
27 This provides the functions that take a user-supplied search query, and
28 provides something that can be given to elasticsearch to get answers.
32 use Koha::SearchEngine::Elasticsearch;
33 $builder = Koha::SearchEngine::Elasticsearch->new();
34 my $simple_query = $builder->build_query("hello");
35 # This is currently undocumented because the original code is undocumented
36 my $adv_query = $builder->build_advanced_query($indexes, $operands, $operators);
42 use base qw(Class::Accessor);
44 use List::MoreUtils qw/ each_array /;
48 use Data::Dumper; # TODO remove
52 my $simple_query = $builder->build_query("hello", %options)
54 This will build a query that can be issued to elasticsearch from the provided
55 string input. This expects a lucene style search form (see
56 L<http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/query-dsl-query-string-query.html#query-string-syntax>
59 It'll make an attempt to respect the various query options.
61 Additional options can be provided with the C<%options> hash.
67 This should be an arrayref of hashrefs, each containing a C<field> and an
68 C<direction> (optional, defaults to C<asc>.) The results will be sorted
69 according to these values. Valid values for C<direction> are 'asc' and 'desc'.
76 my ( $self, $query, %options ) = @_;
78 my $stemming = C4::Context->preference("QueryStemming") || 0;
79 my $auto_truncation = C4::Context->preference("QueryAutoTruncate") || 0;
80 my $weight_fields = C4::Context->preference("QueryWeightFields") || 0;
81 my $fuzzy_enabled = C4::Context->preference("QueryFuzzy") || 0;
83 $query = '*' unless defined $query;
89 fuzziness => $fuzzy_enabled ? 'auto' : '0',
90 default_operator => "AND",
91 default_field => "_all",
95 if ( $options{sort} ) {
96 foreach my $sort ( @{ $options{sort} } ) {
97 my ( $f, $d ) = @$sort{qw/ field direction /};
98 die "Invalid sort direction, $d"
99 if $d && ( $d ne 'asc' && $d ne 'desc' );
100 $d = 'asc' unless $d;
102 # TODO account for fields that don't have a 'phrase' type
103 push @{ $res->{sort} }, { "$f.phrase" => { order => $d } };
107 # See _convert_facets in Search.pm for how these get turned into
108 # things that Koha can use.
110 author => { terms => { field => "author__facet" } },
111 subject => { terms => { field => "subject__facet" } },
112 itype => { terms => { field => "itype__facet" } },
117 =head2 build_browse_query
119 my $browse_query = $builder->build_browse_query($field, $query);
121 This performs a "starts with" style query on a particular field. The field
122 to be searched must have been indexed with an appropriate mapping as a
126 # XXX this isn't really a browse query like we want in the end
127 sub build_browse_query {
128 my ( $self, $field, $query ) = @_;
130 my $fuzzy_enabled = C4::Context->preference("QueryFuzzy") || 0;
132 return { query => '*' } if !defined $query;
134 # TODO this should come from Koha::Elasticsearch
135 my %field_whitelist = (
139 $field = 'title' if !exists $field_whitelist{$field};
143 match_phrase_prefix => {
147 fuzziness => $fuzzy_enabled ? 'auto' : '0',
151 sort => [ { "$field.phrase" => { order => "asc" } } ],
155 =head2 build_query_compat
158 $error, $query, $simple_query, $query_cgi,
159 $query_desc, $limit, $limit_cgi, $limit_desc,
160 $stopwords_removed, $query_type
162 = $builder->build_query_compat( \@operators, \@operands, \@indexes,
163 \@limits, \@sort_by, $scan, $lang );
165 This handles a search using the same api as L<C4::Search::buildQuery> does.
167 A very simple query will go in with C<$operands> set to ['query'], and
168 C<$sort_by> set to ['pubdate_dsc']. This simple case will return with
169 C<$query> set to something that can perform the search, C<$simple_query>
170 set to just the search term, C<$query_cgi> set to something that can
171 reproduce this search, and C<$query_desc> set to something else.
175 sub build_query_compat {
176 my ( $self, $operators, $operands, $indexes, $orig_limits, $sort_by, $scan,
180 #die Dumper ( $self, $operators, $operands, $indexes, $orig_limits, $sort_by, $scan, $lang );
181 my @sort_params = $self->_convert_sort_fields(@$sort_by);
182 my @index_params = $self->_convert_index_fields(@$indexes);
183 my $limits = $self->_fix_limit_special_cases($orig_limits);
185 # Merge the indexes in with the search terms and the operands so that
186 # each search thing is a handy unit.
187 unshift @$operators, undef; # The first one can't have an op
189 my $ea = each_array( @$operands, @$operators, @index_params );
190 while ( my ( $oand, $otor, $index ) = $ea->() ) {
191 next if ( !defined($oand) || $oand eq '' );
192 push @search_params, {
193 operand => $self->_clean_search_term($oand), # the search terms
194 operator => defined($otor) ? uc $otor : undef, # AND and so on
195 $index ? %$index : (),
199 # We build a string query from limits and the queries. An alternative
200 # would be to pass them separately into build_query and let it build
201 # them into a structured ES query itself. Maybe later, though that'd be
203 my $query_str = join( ' AND ',
204 join( ' ', $self->_create_query_string(@search_params) ) || (),
205 $self->_join_queries( $self->_convert_index_strings(@$limits) ) || () );
207 # If there's no query on the left, let's remove the junk left behind
208 $query_str =~ s/^ AND //;
210 $options{sort} = \@sort_params;
211 my $query = $self->build_query( $query_str, %options );
214 # We roughly emulate the CGI parameters of the zebra query builder
215 my $query_cgi = 'idx=kw&q=' . uri_escape( $operands->[0] ) if @$operands;
216 my $simple_query = $operands->[0] if @$operands == 1;
217 my $query_desc = $simple_query;
218 my $limit = $self->_join_queries( $self->_convert_index_strings(@$limits));
220 '&limit=' . join( '&limit=', map { uri_escape($_) } @$orig_limits );
221 my $limit_desc = "$limit";
223 undef, $query, $simple_query, $query_cgi, $query_desc,
224 $limit, $limit_cgi, $limit_desc, undef, undef
228 =head2 build_authorities_query
230 my $query = $builder->build_authorities_query(\%search);
232 This takes a nice description of an authority search and turns it into a black-box
233 query that can then be passed to the appropriate searcher.
235 The search description is a hashref that looks something like:
240 where => 'Heading', # search the main entry
241 operator => 'exact', # require an exact match
242 value => 'frogs', # the search string
245 where => '', # search all entries
246 operator => '', # default keyword, right truncation
254 authtypecode => 'TOPIC_TERM',
259 sub build_authorities_query {
260 my ($self, $search) = @_;
262 # Start by making the query parts
265 foreach my $s ( @{ $search->{searches} } ) {
266 my ($wh, $op, $val) = @{ $s }{qw(where operator value)};
267 $wh = '_all' if $wh eq '';
268 if ($op eq 'is' || $op eq '=') {
269 # look for something that matches completely
270 # note, '=' is about numerical vals. May need special handling.
271 # _allphrase is a special field that only groups the exact
272 # matches. Also, we lowercase our search because the ES
273 # index lowercases its values, and term searches don't get the
274 # search analyzer applied to them.
275 push @filter_parts, { term => { "$wh.phrase" => lc $val }};
276 } elsif ($op eq 'exact') {
277 # left and right truncation, otherwise an exact phrase
278 push @query_parts, { match_phrase => { $wh => $val }};
279 } elsif ($op eq 'start') {
281 push @query_parts, { wildcard => { "$wh.phrase" => lc "$val*" }};
283 # regular wordlist stuff
284 push @query_parts, { match => { $wh => $val }};
287 # Merge the query and filter parts appropriately
288 # 'should' behaves like 'or', if we want 'and', use 'must'
289 my $query_part = { bool => { should => \@query_parts } };
290 my $filter_part = { bool => { should => \@filter_parts }};
291 # extract the sort stuff
292 my %sort = ( sort => [ $search->{sort} ] ) if exists $search->{sort};
295 $query = { query => { filtered => { filter => $filter_part, query => $query_part }}};
297 $query = { query => $query_part };
299 $query = { %$query, %sort };
304 =head2 build_authorities_query_compat
307 $builder->build_authorities_query_compat( \@marclist, \@and_or,
308 \@excluding, \@operator, \@value, $authtypecode, $orderby );
310 This builds a query for searching for authorities, in the style of
311 L<C4::AuthoritiesMarc::SearchAuthorities>.
319 An arrayref containing where the particular term should be searched for.
320 Options are: mainmainentry, mainentry, match, match-heading, see-from, and
321 thesaurus. If left blank, any field is used.
325 Totally ignored. It is never used in L<C4::AuthoritiesMarc::SearchAuthorities>.
333 What form of search to do. Options are: is (phrase, no trunction, whole field
334 must match), = (number exact match), exact (phrase, but with left and right
335 truncation). If left blank, then word list, right truncted, anywhere is used.
339 The actual user-provided string value to search for.
343 The authority type code to search within. If blank, then all will be searched.
347 The order to sort the results by. Options are Relevance, HeadingAsc,
348 HeadingDsc, AuthidAsc, AuthidDsc.
352 marclist, operator, and value must be the same length, and the values at
353 index /i/ all relate to each other.
355 This returns a query, which is a black box object that can be passed to the
356 appropriate search object.
360 sub build_authorities_query_compat {
361 my ( $self, $marclist, $and_or, $excluding, $operator, $value,
362 $authtypecode, $orderby )
365 # This turns the old-style many-options argument form into a more
366 # extensible hash form that is understood by L<build_authorities_query>.
369 my %koha_to_index_name = (
370 mainmainentry => 'Heading-Main',
371 mainentry => 'Heading',
373 'match-heading' => 'Match-heading',
374 'see-from' => 'Match-heading-see-from',
375 thesaurus => 'Subject-heading-thesaurus',
379 # Make sure everything exists
380 foreach my $m (@$marclist) {
381 confess "Invalid marclist field provided: $m" unless exists $koha_to_index_name{$m};
383 for ( my $i = 0 ; $i < @$value ; $i++ ) {
386 where => $koha_to_index_name{$marclist->[$i]},
387 operator => $operator->[$i],
388 value => $value->[$i],
394 ( $orderby =~ /^Heading/ ) ? 'Heading'
395 : ( $orderby =~ /^Auth/ ) ? 'Local-Number'
398 my $sort_order = ( $orderby =~ /Asc$/ ) ? 'asc' : 'desc';
399 %sort = ( $sort_field => $sort_order, );
402 searches => \@searches,
403 authtypecode => $authtypecode,
405 $search{sort} = \%sort if %sort;
406 my $query = $self->build_authorities_query( \%search );
410 =head2 _convert_sort_fields
412 my @sort_params = _convert_sort_fields(@sort_by)
414 Converts the zebra-style sort index information into elasticsearch-style.
416 C<@sort_by> is the same as presented to L<build_query_compat>, and it returns
417 something that can be sent to L<build_query>.
421 sub _convert_sort_fields {
422 my ( $self, @sort_by ) = @_;
424 # Turn the sorting into something we care about.
425 my %sort_field_convert = (
426 acqdate => 'acqdate',
428 call_number => 'callnum',
429 popularity => 'issues',
430 relevance => undef, # default
432 pubdate => 'pubdate',
434 my %sort_order_convert =
435 ( qw( dsc desc ), qw( asc asc ), qw( az asc ), qw( za desc ) );
437 # Convert the fields and orders, drop anything we don't know about.
438 grep { $_->{field} } map {
439 my ( $f, $d ) = split /_/;
441 field => $sort_field_convert{$f},
442 direction => $sort_order_convert{$d}
447 =head2 _convert_index_fields
449 my @index_params = $self->_convert_index_fields(@indexes);
451 Converts zebra-style search index notation into elasticsearch-style.
453 C<@indexes> is an array of index names, as presented to L<build_query_compat>,
454 and it returns something that can be sent to L<build_query>.
456 B<TODO>: this will pull from the elasticsearch mappings table to figure out
461 our %index_field_convert = (
467 'se' => 'title-series',
468 'callnum' => 'callnum',
471 'branch' => 'homebranch',
477 sub _convert_index_fields {
478 my ( $self, @indexes ) = @_;
480 my %index_type_convert =
481 ( __default => undef, phr => 'phrase', rtrn => 'right-truncate' );
483 # Convert according to our table, drop anything that doesn't convert.
484 # If a field starts with mc- we save it as it's used (and removed) later
485 # when joining things, to indicate we make it an 'OR' join.
486 # (Sorry, this got a bit ugly after special cases were found.)
487 grep { $_->{field} } map {
488 my ( $f, $t ) = split /,/;
495 field => $index_field_convert{$f},
496 type => $index_type_convert{ $t // '__default' }
498 $r->{field} = ($mc . $r->{field}) if $mc && $r->{field};
503 =head2 _convert_index_strings
505 my @searches = $self->_convert_index_strings(@searches);
507 Similar to L<_convert_index_fields>, this takes strings of the form
508 B<field:search term> and rewrites the field from zebra-style to
509 elasticsearch-style. Anything it doesn't understand is returned verbatim.
513 sub _convert_index_strings {
514 my ( $self, @searches ) = @_;
516 foreach my $s (@searches) {
518 my ( $field, $term ) = $s =~ /^\s*([\w,-]*?):(.*)/;
519 unless ( defined($field) && defined($term) ) {
523 my ($conv) = $self->_convert_index_fields($field);
524 unless ( defined($conv) ) {
528 push @res, $conv->{field} . ":"
529 . $self->_modify_string_by_type( %$conv, operand => $term );
534 =head2 _convert_index_strings_freeform
536 my $search = $self->_convert_index_strings_freeform($search);
538 This is similar to L<_convert_index_strings>, however it'll search out the
539 things to change within the string. So it can handle strings such as
540 C<(su:foo) AND (su:bar)>, converting the C<su> appropriately.
542 If there is something of the form "su,complete-subfield" or something, the
543 second part is stripped off as we can't yet handle that. Making it work
544 will have to wait for a real query parser.
548 sub _convert_index_strings_freeform {
549 my ( $self, $search ) = @_;
550 while ( my ( $zeb, $es ) = each %index_field_convert ) {
551 $search =~ s/\b$zeb(?:,[\w-]*)?:/$es:/g;
556 =head2 _modify_string_by_type
558 my $str = $self->_modify_string_by_type(%index_field);
560 If you have a search term (operand) and a type (phrase, right-truncated), this
561 will convert the string to have the function in lucene search terms, e.g.
562 wrapping quotes around it.
566 sub _modify_string_by_type {
567 my ( $self, %idx ) = @_;
569 my $type = $idx{type} || '';
570 my $str = $idx{operand};
571 return $str unless $str; # Empty or undef, we can't use it.
573 $str .= '*' if $type eq 'right-truncate';
574 $str = '"' . $str . '"' if $type eq 'phrase';
580 my $query_str = $self->_join_queries(@query_parts);
582 This takes a list of query parts, that might be search terms on their own, or
583 booleaned together, or specifying fields, or whatever, wraps them in
584 parentheses, and ANDs them all together. Suitable for feeding to the ES
587 Note: doesn't AND them together if they specify an index that starts with "mc"
588 as that was a special case in the original code for dealing with multiple
589 choice options (you can't search for something that has an itype of A and
590 and itype of B otherwise.)
595 my ( $self, @parts ) = @_;
597 my @norm_parts = grep { defined($_) && $_ ne '' && $_ !~ /^mc-/ } @parts;
599 map { s/^mc-//r } grep { defined($_) && $_ ne '' && $_ =~ /^mc-/ } @parts;
600 return () unless @norm_parts + @mc_parts;
601 return ( @norm_parts, @mc_parts )[0] if @norm_parts + @mc_parts == 1;
603 @mc_parts ? '(' . ( join ' OR ', map { "($_)" } @mc_parts ) . ')' : ();
605 # Handy trick: $x || () inside a join means that if $x ends up as an
606 # empty string, it gets replaced with (), which makes join ignore it.
607 # (bad effect: this'll also happen to '0', this hopefully doesn't matter
610 join( ' AND ', map { "($_)" } @norm_parts ) || (),
616 my @phrased_queries = $self->_make_phrases(@query_parts);
618 This takes the supplied queries and forces them to be phrases by wrapping
619 quotes around them. It understands field prefixes, e.g. 'subject:' and puts
620 the quotes outside of them if they're there.
625 my ( $self, @parts ) = @_;
626 map { s/^\s*(\w*?:)(.*)$/$1"$2"/r } @parts;
629 =head2 _create_query_string
631 my @query_strings = $self->_create_query_string(@queries);
633 Given a list of hashrefs, it will turn them into a lucene-style query string.
634 The hash should contain field, type (both for the indexes), operator, and
639 sub _create_query_string {
640 my ( $self, @queries ) = @_;
643 my $otor = $_->{operator} ? $_->{operator} . ' ' : '';
644 my $field = $_->{field} ? $_->{field} . ':' : '';
646 my $oand = $self->_modify_string_by_type(%$_);
647 "$otor($field$oand)";
651 =head2 _clean_search_term
653 my $term = $self->_clean_search_term($term);
655 This cleans a search term by removing any funny characters that may upset
656 ES and give us an error. It also calls L<_convert_index_strings_freeform>
657 to ensure those parts are correct.
661 sub _clean_search_term {
662 my ( $self, $term ) = @_;
664 $term = $self->_convert_index_strings_freeform($term);
666 # Some hardcoded searches (like with authorities) produce things like
667 # 'an=123', when it ought to be 'an:123'.
672 =head2 _fix_limit_special_cases
674 my $limits = $self->_fix_limit_special_cases($limits);
676 This converts any special cases that the limit specifications have into things
677 that are more readily processable by the rest of the code.
679 The argument should be an arrayref, and it'll return an arrayref.
683 sub _fix_limit_special_cases {
684 my ( $self, $limits ) = @_;
687 foreach my $l (@$limits) {
689 # This is set up by opac-search.pl
690 if ( $l =~ /^yr,st-numeric,ge=/ ) {
691 my ( $start, $end ) =
692 ( $l =~ /^yr,st-numeric,ge=(.*) and yr,st-numeric,le=(.*)$/ );
693 next unless defined($start) && defined($end);
694 push @new_lim, "copydate:[$start TO $end]";
696 elsif ( $l =~ /^yr,st-numeric=/ ) {
697 my ($date) = ( $l =~ /^yr,st-numeric=(.*)$/ );
698 next unless defined($date);
699 push @new_lim, "copydate:$date";
701 elsif ( $l =~ /^available$/ ) {
702 push @new_lim, 'onloan:false';