Koha/OAI/Server/ListBase.pm

   1 package Koha::OAI::Server::ListBase;
   2
   3 # Copyright The National Library of Finland, University of Helsinki 2016-2017
   4 #
   5 # This file is part of Koha.
   6 #
   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.
  11 #
  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.
  16 #
  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>.
  19
  20 =head1 NAME
  21
  22 Koha::OAI::Server::ListBase - OAI ListIdentifiers/ListRecords shared functionality
  23
  24 =head1 DESCRIPTION
  25
  26 Koha::OAI::Server::ListBase contains OAI-PMH functions shared by ListIdentifiers and ListRecords.
  27
  28 =cut
  29
  30 use Modern::Perl;
  31 use C4::Biblio;
  32 use HTTP::OAI;
  33 use Koha::OAI::Server::ResumptionToken;
  34 use Koha::OAI::Server::Record;
  35 use Koha::OAI::Server::DeletedRecord;
  36 use C4::OAI::Sets;
  37 use MARC::File::XML;
  38
  39 sub GetRecords {
  40     my ($class, $self, $repository, $metadata, %args) = @_;
  41
  42     my $token = Koha::OAI::Server::ResumptionToken->new( %args );
  43     my $dbh = C4::Context->dbh;
  44     my $set;
  45     if ( defined $token->{'set'} ) {
  46         $set = GetOAISetBySpec($token->{'set'});
  47     }
  48     my $offset = $token->{offset};
  49     my $deleted = defined $token->{deleted} ? $token->{deleted} : 0;
  50     my $deleted_count = defined $token->{deleted_count} ? $token->{deleted_count} : 0;
  51     my $max = $repository->{koha_max_count};
  52     my $count = 0;
  53     my $format = $args{metadataPrefix} || $token->{metadata_prefix};
  54     my $include_items = $repository->items_included( $format );
  55
  56     # Since creating a union of normal and deleted record tables would be a heavy
  57     # operation in a large database, build results in two stages:
  58     # first deleted records ($deleted == 1), then normal records ($deleted == 0)
  59     STAGELOOP:
  60     for ( ; $deleted >= 0; $deleted-- ) {
  61         my $table = $deleted ? 'deletedbiblio_metadata' : 'biblio_metadata';
  62         my $sql = "
  63             SELECT biblionumber
  64             FROM $table
  65             WHERE (timestamp >= ? AND timestamp <= ?)
  66         ";
  67         my @bind_params = ($token->{'from_arg'}, $token->{'until_arg'});
  68
  69         if ($include_items) {
  70             $sql .= "
  71                 OR biblionumber IN (SELECT biblionumber from deleteditems WHERE timestamp >= ? AND timestamp <= ?)
  72             ";
  73             push @bind_params, ($token->{'from_arg'}, $token->{'until_arg'});
  74             if (!$deleted) {
  75                 $sql .= "
  76                     OR biblionumber IN (SELECT biblionumber from items WHERE timestamp >= ? AND timestamp <= ?)
  77                 ";
  78                 push @bind_params, ($token->{'from_arg'}, $token->{'until_arg'});
  79             }
  80         }
  81
  82         $sql .= "
  83             ORDER BY biblionumber
  84         ";
  85
  86         # Use a subquery for sets since it allows us to use an index in
  87         # biblioitems table and is quite a bit faster than a join.
  88         if (defined $set) {
  89             $sql = "
  90                 SELECT bi.* FROM ($sql) bi
  91                   WHERE bi.biblionumber in (SELECT osb.biblionumber FROM oai_sets_biblios osb WHERE osb.set_id = ?)
  92             ";
  93             push @bind_params, $set->{'id'};
  94         }
  95
  96         $sql .= "
  97             LIMIT " . ($max + 1) . "
  98             OFFSET " . ($offset - $deleted_count);
  99
 100         my $sth = $dbh->prepare( $sql ) || die( 'Could not prepare statement: ' . $dbh->errstr );
 101
 102         if ( $deleted ) {
 103             $sql = "
 104                 SELECT MAX(timestamp)
 105                 FROM (
 106                     SELECT timestamp FROM deletedbiblio_metadata WHERE biblionumber = ?
 107                     UNION
 108                     SELECT timestamp FROM deleteditems WHERE biblionumber = ?
 109                 ) bis
 110             ";
 111         } else {
 112             $sql = "
 113                 SELECT MAX(timestamp)
 114                 FROM (
 115                     SELECT timestamp FROM biblio_metadata WHERE biblionumber = ?
 116                     UNION
 117                     SELECT timestamp FROM deleteditems WHERE biblionumber = ?
 118                     UNION
 119                     SELECT timestamp FROM items WHERE biblionumber = ?
 120                 ) bi
 121             ";
 122         }
 123         my $record_sth = $dbh->prepare( $sql ) || die( 'Could not prepare statement: ' . $dbh->errstr );
 124
 125         $sth->execute( @bind_params ) || die( 'Could not execute statement: ' . $sth->errstr );
 126         while ( my ($biblionumber) = $sth->fetchrow ) {
 127             $count++;
 128             if ( $count > $max ) {
 129                 $self->resumptionToken(
 130                     Koha::OAI::Server::ResumptionToken->new(
 131                         metadataPrefix  => $token->{metadata_prefix},
 132                         from            => $token->{from},
 133                         until           => $token->{until},
 134                         offset          => $token->{offset} + $max,
 135                         set             => $token->{set},
 136                         deleted         => $deleted,
 137                         deleted_count   => $deleted_count
 138                     )
 139                 );
 140                 last STAGELOOP;
 141             }
 142             my @params = $deleted ? ( $biblionumber, $biblionumber ) : ( $biblionumber, $biblionumber, $biblionumber );
 143             $record_sth->execute( @params ) || die( 'Could not execute statement: ' . $sth->errstr );
 144
 145             my ($timestamp) = $record_sth->fetchrow;
 146
 147             my $oai_sets = GetOAISetsBiblio($biblionumber);
 148             my @setSpecs;
 149             foreach ( @$oai_sets ) {
 150                 push @setSpecs, $_->{spec};
 151             }
 152             if ( $metadata ) {
 153                 my $marcxml = !$deleted ? $repository->get_biblio_marcxml($biblionumber, $format) : undef;
 154                 if ( $marcxml ) {
 155                   $self->record( Koha::OAI::Server::Record->new(
 156                       $repository, $marcxml, $timestamp, \@setSpecs,
 157                       identifier      => $repository->{ koha_identifier } . ':' . $biblionumber,
 158                       metadataPrefix  => $token->{metadata_prefix}
 159                   ) );
 160                 } else {
 161                   $self->record( Koha::OAI::Server::DeletedRecord->new(
 162                       $timestamp, \@setSpecs, identifier => $repository->{ koha_identifier } . ':' . $biblionumber
 163                   ) );
 164                 }
 165             } else {
 166                 $timestamp =~ s/ /T/;
 167                 $timestamp .= 'Z';
 168                 $self->identifier( HTTP::OAI::Header->new(
 169                     identifier => $repository->{ koha_identifier} . ':' . $biblionumber,
 170                     datestamp  => $timestamp,
 171                     status     => $deleted ? 'deleted' : undef
 172                 ) );
 173             }
 174         }
 175         # Store offset and deleted record count
 176         $offset += $count;
 177         $deleted_count = $offset if ($deleted);
 178     }
 179     return $count;
 180 }
 181
 182 1;