Koha/Z3950Responder/ZebraSession.pm

   1 package Koha::Z3950Responder::ZebraSession;
   2
   3 # Copyright ByWater Solutions 2016
   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 use Modern::Perl;
  21
  22 use base qw( Koha::Z3950Responder::Session );
  23
  24 use Koha::Logger;
  25
  26 use ZOOM;
  27
  28 =head1 NAME
  29
  30 Koha::Z3950Responder::ZebraSession
  31
  32 =head1 SYNOPSIS
  33
  34 Zebra-specific session class that uses C<Koha::Session> as the base class.
  35
  36 =head1 FUNCTIONS
  37
  38 =head2 INSTANCE METHODS
  39
  40 =head3 start_search
  41
  42     my ($resultset, $hits) = $self->_start_search( $args, $self->{server}->{num_to_prefetch} );
  43
  44 Connect to Zebra and do the search
  45
  46 =cut
  47
  48 sub start_search {
  49     my ( $self, $args, $num_to_prefetch, $in_retry ) = @_;
  50
  51     my $database = $args->{DATABASES}->[0];
  52     my ( $connection, $results );
  53
  54     eval {
  55         $connection = C4::Context->Zconn(
  56             # We're depending on the caller to have done some validation.
  57             $database eq 'biblios' ? 'biblioserver' : 'authorityserver',
  58             0 # No, no async, doesn't really help much for single-server searching
  59         );
  60
  61         $results = $connection->search_pqf( $args->{QUERY} );
  62
  63         $self->log_debug('    retry successful') if ($in_retry);
  64     };
  65     if ($@) {
  66         die $@ if ( ref($@) ne 'ZOOM::Exception' );
  67
  68         if ( $@->diagset() eq 'ZOOM' && $@->code() == 10004 && !$in_retry ) {
  69             $self->log_debug('    upstream server lost connection, retrying');
  70             return $self->_start_search( $args, $num_to_prefetch, 1 );
  71         }
  72
  73         $self->_set_error_from_zoom( $args, $@ );
  74         $connection = undef;
  75     }
  76
  77     my $hits = $results ? $results->size() : -1;
  78     my $resultset = {
  79         database => $database,
  80         connection => $connection,
  81         results => $results,
  82         query => $args->{QUERY},
  83         hits => $hits
  84     };
  85
  86     return ( $resultset, $hits );
  87 }
  88
  89 =head3 fetch_record
  90
  91     my $record = $self->_fetch_record( $resultset, $args, $offset, $server->{num_to_prefetch} );
  92
  93 Fetch a record from Zebra. Caches records in session to avoid too many fetches.
  94
  95 =cut
  96
  97 sub fetch_record {
  98     my ( $self, $resultset, $args, $index, $num_to_prefetch ) = @_;
  99
 100     my $record;
 101
 102     eval {
 103         if ( !$resultset->{results}->record_immediate( $index ) ) {
 104             my $start = $num_to_prefetch ? int( $index / $num_to_prefetch ) * $num_to_prefetch : $index;
 105
 106             if ( $start + $num_to_prefetch >= $resultset->{results}->size() ) {
 107                 $num_to_prefetch = $resultset->{results}->size() - $start;
 108             }
 109
 110             $self->log_debug("    fetch uncached, fetching $num_to_prefetch records starting at $start");
 111
 112             $resultset->{results}->records( $start, $num_to_prefetch, 0 );
 113         }
 114
 115         $record = $resultset->{results}->record_immediate( $index )->raw();
 116     };
 117     if ($@) {
 118         die $@ if ( ref($@) ne 'ZOOM::Exception' );
 119         $self->_set_error_from_zoom( $args, $@ );
 120         return;
 121     } else {
 122         return $record;
 123     }
 124 }
 125
 126 =head3 close_handler
 127
 128 Callback that is called when a session is terminated
 129
 130 =cut
 131
 132 sub close_handler {
 133     my ( $self, $args ) = @_;
 134
 135     foreach my $resultset ( values %{ $self->{resultsets} } ) {
 136         $resultset->{results}->destroy();
 137     }
 138 }
 139
 140 =head3 _set_error_from_zoom
 141
 142     $self->_set_error_from_zoom( $args, $@ );
 143
 144 Log and set error code and diagnostic message from a ZOOM exception
 145
 146 =cut
 147
 148 sub _set_error_from_zoom {
 149     my ( $self, $args, $exception ) = @_;
 150
 151     $self->set_error( $args, $self->ERR_TEMPORARY_ERROR, 'Cannot connect to upstream server' );
 152     $self->log_error(
 153         "Zebra upstream error: " .
 154         $exception->message() . " (" .
 155         $exception->code() . ") " .
 156         ( $exception->addinfo() // '' ) . " " .
 157         $exception->diagset()
 158     );
 159 }
 160
 161 1;