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 $limit = 'and ' . join( ' and ', @$limits );
220 '&limit=' . join( '&limit=', map { uri_escape($_) } @$orig_limits );
221 my $limit_desc = "@$limits";
224 undef, $query, $simple_query, $query_cgi, $query_desc,
225 $limit, $limit_cgi, $limit_desc, undef, undef
229 =head2 build_authorities_query
231 my $query = $builder->build_authorities_query(\%search);
233 This takes a nice description of an authority search and turns it into a black-box
234 query that can then be passed to the appropriate searcher.
236 The search description is a hashref that looks something like:
241 where => 'Heading', # search the main entry
242 operator => 'exact', # require an exact match
243 value => 'frogs', # the search string
246 where => '', # search all entries
247 operator => '', # default keyword, right truncation
255 authtypecode => 'TOPIC_TERM',
260 sub build_authorities_query {
261 my ($self, $search) = @_;
263 # Start by making the query parts
266 foreach my $s ( @{ $search->{searches} } ) {
267 my ($wh, $op, $val) = @{ $s }{qw(where operator value)};
268 $wh = '_all' if $wh eq '';
269 if ($op eq 'is' || $op eq '=') {
270 # look for something that matches completely
271 # note, '=' is about numerical vals. May need special handling.
272 # _allphrase is a special field that only groups the exact
273 # matches. Also, we lowercase our search because the ES
274 # index lowercases its values, and term searches don't get the
275 # search analyzer applied to them.
276 push @filter_parts, { term => { "$wh.phrase" => lc $val }};
277 } elsif ($op eq 'exact') {
278 # left and right truncation, otherwise an exact phrase
279 push @query_parts, { match_phrase => { $wh => $val }};
280 } elsif ($op eq 'start') {
282 push @query_parts, { wildcard => { "$wh.phrase" => lc "$val*" }};
284 # regular wordlist stuff
285 push @query_parts, { match => { $wh => $val }};
288 # Merge the query and filter parts appropriately
289 # 'should' behaves like 'or', if we want 'and', use 'must'
290 my $query_part = { bool => { should => \@query_parts } };
291 my $filter_part = { bool => { should => \@filter_parts }};
292 # extract the sort stuff
293 my %sort = ( sort => [ $search->{sort} ] ) if exists $search->{sort};
296 $query = { query => { filtered => { filter => $filter_part, query => $query_part }}};
298 $query = { query => $query_part };
300 $query = { %$query, %sort };
305 =head2 build_authorities_query_compat
308 $builder->build_authorities_query_compat( \@marclist, \@and_or,
309 \@excluding, \@operator, \@value, $authtypecode, $orderby );
311 This builds a query for searching for authorities, in the style of
312 L<C4::AuthoritiesMarc::SearchAuthorities>.
320 An arrayref containing where the particular term should be searched for.
321 Options are: mainmainentry, mainentry, match, match-heading, see-from, and
322 thesaurus. If left blank, any field is used.
326 Totally ignored. It is never used in L<C4::AuthoritiesMarc::SearchAuthorities>.
334 What form of search to do. Options are: is (phrase, no trunction, whole field
335 must match), = (number exact match), exact (phrase, but with left and right
336 truncation). If left blank, then word list, right truncted, anywhere is used.
340 The actual user-provided string value to search for.
344 The authority type code to search within. If blank, then all will be searched.
348 The order to sort the results by. Options are Relevance, HeadingAsc,
349 HeadingDsc, AuthidAsc, AuthidDsc.
353 marclist, operator, and value must be the same length, and the values at
354 index /i/ all relate to each other.
356 This returns a query, which is a black box object that can be passed to the
357 appropriate search object.
361 sub build_authorities_query_compat {
362 my ( $self, $marclist, $and_or, $excluding, $operator, $value,
363 $authtypecode, $orderby )
366 # This turns the old-style many-options argument form into a more
367 # extensible hash form that is understood by L<build_authorities_query>.
370 my %koha_to_index_name = (
371 mainmainentry => 'Heading-Main',
372 mainentry => 'Heading',
374 'match-heading' => 'Match-heading',
375 'see-from' => 'Match-heading-see-from',
376 thesaurus => 'Subject-heading-thesaurus',
380 # Make sure everything exists
381 foreach my $m (@$marclist) {
382 confess "Invalid marclist field provided: $m" unless exists $koha_to_index_name{$m};
384 for ( my $i = 0 ; $i < @$value ; $i++ ) {
387 where => $koha_to_index_name{$marclist->[$i]},
388 operator => $operator->[$i],
389 value => $value->[$i],
395 ( $orderby =~ /^Heading/ ) ? 'Heading'
396 : ( $orderby =~ /^Auth/ ) ? 'Local-Number'
399 my $sort_order = ( $orderby =~ /Asc$/ ) ? 'asc' : 'desc';
400 %sort = ( $sort_field => $sort_order, );
403 searches => \@searches,
404 authtypecode => $authtypecode,
406 $search{sort} = \%sort if %sort;
407 my $query = $self->build_authorities_query( \%search );
411 =head2 _convert_sort_fields
413 my @sort_params = _convert_sort_fields(@sort_by)
415 Converts the zebra-style sort index information into elasticsearch-style.
417 C<@sort_by> is the same as presented to L<build_query_compat>, and it returns
418 something that can be sent to L<build_query>.
422 sub _convert_sort_fields {
423 my ( $self, @sort_by ) = @_;
425 # Turn the sorting into something we care about.
426 my %sort_field_convert = (
427 acqdate => 'acqdate',
429 call_number => 'callnum',
430 popularity => 'issues',
431 relevance => undef, # default
433 pubdate => 'pubdate',
435 my %sort_order_convert =
436 ( qw( dsc desc ), qw( asc asc ), qw( az asc ), qw( za desc ) );
438 # Convert the fields and orders, drop anything we don't know about.
439 grep { $_->{field} } map {
440 my ( $f, $d ) = split /_/;
442 field => $sort_field_convert{$f},
443 direction => $sort_order_convert{$d}
448 =head2 _convert_index_fields
450 my @index_params = $self->_convert_index_fields(@indexes);
452 Converts zebra-style search index notation into elasticsearch-style.
454 C<@indexes> is an array of index names, as presented to L<build_query_compat>,
455 and it returns something that can be sent to L<build_query>.
457 B<TODO>: this will pull from the elasticsearch mappings table to figure out
462 our %index_field_convert = (
468 'se' => 'title-series',
469 'callnum' => 'callnum',
470 'mc-itype' => 'itype',
472 'branch' => 'homebranch',
478 sub _convert_index_fields {
479 my ( $self, @indexes ) = @_;
481 my %index_type_convert =
482 ( __default => undef, phr => 'phrase', rtrn => 'right-truncate' );
484 # Convert according to our table, drop anything that doesn't convert
485 grep { $_->{field} } map {
486 my ( $f, $t ) = split /,/;
488 field => $index_field_convert{$f},
489 type => $index_type_convert{ $t // '__default' }
494 =head2 _convert_index_strings
496 my @searches = $self->_convert_index_strings(@searches);
498 Similar to L<_convert_index_fields>, this takes strings of the form
499 B<field:search term> and rewrites the field from zebra-style to
500 elasticsearch-style. Anything it doesn't understand is returned verbatim.
504 sub _convert_index_strings {
505 my ( $self, @searches ) = @_;
508 foreach my $s (@searches) {
510 my ( $field, $term ) = $s =~ /^\s*([\w,-]*?):(.*)/;
511 unless ( defined($field) && defined($term) ) {
515 my ($conv) = $self->_convert_index_fields($field);
516 unless ( defined($conv) ) {
520 push @res, $conv->{field} . ":"
521 . $self->_modify_string_by_type( %$conv, operand => $term );
526 =head2 _convert_index_strings_freeform
528 my $search = $self->_convert_index_strings_freeform($search);
530 This is similar to L<_convert_index_strings>, however it'll search out the
531 things to change within the string. So it can handle strings such as
532 C<(su:foo) AND (su:bar)>, converting the C<su> appropriately.
534 If there is something of the form "su,complete-subfield" or something, the
535 second part is stripped off as we can't yet handle that. Making it work
536 will have to wait for a real query parser.
540 sub _convert_index_strings_freeform {
541 my ( $self, $search ) = @_;
542 while ( my ( $zeb, $es ) = each %index_field_convert ) {
543 $search =~ s/\b$zeb(?:,[\w-]*)?:/$es:/g;
548 =head2 _modify_string_by_type
550 my $str = $self->_modify_string_by_type(%index_field);
552 If you have a search term (operand) and a type (phrase, right-truncated), this
553 will convert the string to have the function in lucene search terms, e.g.
554 wrapping quotes around it.
558 sub _modify_string_by_type {
559 my ( $self, %idx ) = @_;
561 my $type = $idx{type} || '';
562 my $str = $idx{operand};
563 return $str unless $str; # Empty or undef, we can't use it.
565 $str .= '*' if $type eq 'right-truncate';
566 $str = '"' . $str . '"' if $type eq 'phrase';
572 my $query_str = $self->_join_queries(@query_parts);
574 This takes a list of query parts, that might be search terms on their own, or
575 booleaned together, or specifying fields, or whatever, wraps them in
576 parentheses, and ANDs them all together. Suitable for feeding to the ES
582 my ( $self, @parts ) = @_;
584 @parts = grep { defined($_) && $_ ne '' } @parts;
585 return () unless @parts;
586 return $parts[0] if @parts < 2;
587 join ' AND ', map { "($_)" } @parts;
592 my @phrased_queries = $self->_make_phrases(@query_parts);
594 This takes the supplied queries and forces them to be phrases by wrapping
595 quotes around them. It understands field prefixes, e.g. 'subject:' and puts
596 the quotes outside of them if they're there.
601 my ( $self, @parts ) = @_;
602 map { s/^\s*(\w*?:)(.*)$/$1"$2"/r } @parts;
605 =head2 _create_query_string
607 my @query_strings = $self->_create_query_string(@queries);
609 Given a list of hashrefs, it will turn them into a lucene-style query string.
610 The hash should contain field, type (both for the indexes), operator, and
615 sub _create_query_string {
616 my ( $self, @queries ) = @_;
619 my $otor = $_->{operator} ? $_->{operator} . ' ' : '';
620 my $field = $_->{field} ? $_->{field} . ':' : '';
622 my $oand = $self->_modify_string_by_type(%$_);
623 "$otor($field$oand)";
627 =head2 _clean_search_term
629 my $term = $self->_clean_search_term($term);
631 This cleans a search term by removing any funny characters that may upset
632 ES and give us an error. It also calls L<_convert_index_strings_freeform>
633 to ensure those parts are correct.
637 sub _clean_search_term {
638 my ( $self, $term ) = @_;
640 $term = $self->_convert_index_strings_freeform($term);
642 # Some hardcoded searches (like with authorities) produce things like
643 # 'an=123', when it ought to be 'an:123'.
648 =head2 _fix_limit_special_cases
650 my $limits = $self->_fix_limit_special_cases($limits);
652 This converts any special cases that the limit specifications have into things
653 that are more readily processable by the rest of the code.
655 The argument should be an arrayref, and it'll return an arrayref.
659 sub _fix_limit_special_cases {
660 my ( $self, $limits ) = @_;
663 foreach my $l (@$limits) {
665 # This is set up by opac-search.pl
666 if ( $l =~ /^yr,st-numeric,ge=/ ) {
667 my ( $start, $end ) =
668 ( $l =~ /^yr,st-numeric,ge=(.*) and yr,st-numeric,le=(.*)$/ );
669 next unless defined($start) && defined($end);
670 push @new_lim, "copydate:[$start TO $end]";
672 elsif ( $l =~ /^yr,st-numeric=/ ) {
673 my ($date) = ( $l =~ /^yr,st-numeric=(.*)$/ );
674 next unless defined($date);
675 push @new_lim, "copydate:$date";
677 elsif ( $l =~ /^available$/ ) {
678 push @new_lim, 'onloan:false';