Koha/Z3950Responder/ZebraSession.pm

   1 #!/usr/bin/perl
   2
   3 package Koha::Z3950Responder::ZebraSession;
   4
   5 # Copyright ByWater Solutions 2016
   6 #
   7 # This file is part of Koha.
   8 #
   9 # Koha is free software; you can redistribute it and/or modify it
  10 # under the terms of the GNU General Public License as published by
  11 # the Free Software Foundation; either version 3 of the License, or
  12 # (at your option) any later version.
  13 #
  14 # Koha is distributed in the hope that it will be useful, but
  15 # WITHOUT ANY WARRANTY; without even the implied warranty of
  16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17 # GNU General Public License for more details.
  18 #
  19 # You should have received a copy of the GNU General Public License
  20 # along with Koha; if not, see <http://www.gnu.org/licenses>.
  21
  22 use Modern::Perl;
  23
  24 use base qw( Koha::Z3950Responder::Session );
  25
  26 use Koha::Logger;
  27
  28 use ZOOM;
  29
  30 =head1 NAME
  31
  32 Koha::Z3950Responder::ZebraSession
  33
  34 =head1 SYNOPSIS
  35
  36 Zebra-specific session class that uses C<Koha::Session> as the base class.
  37
  38 =head1 FUNCTIONS
  39
  40 =head2 INSTANCE METHODS
  41
  42 =head3 start_search
  43
  44     my ($resultset, $hits) = $self->_start_search( $args, $self->{server}->{num_to_prefetch} );
  45
  46 Connect to Zebra and do the search
  47
  48 =cut
  49
  50 sub start_search {
  51     my ( $self, $args, $num_to_prefetch, $in_retry ) = @_;
  52
  53     my $database = $args->{DATABASES}->[0];
  54     my ( $connection, $results );
  55
  56     eval {
  57         $connection = C4::Context->Zconn(
  58             # We're depending on the caller to have done some validation.
  59             $database eq 'biblios' ? 'biblioserver' : 'authorityserver',
  60             0 # No, no async, doesn't really help much for single-server searching
  61         );
  62
  63         $results = $connection->search_pqf( $args->{QUERY} );
  64
  65         $self->log_debug('    retry successful') if ($in_retry);
  66     };
  67     if ($@) {
  68         die $@ if ( ref($@) ne 'ZOOM::Exception' );
  69
  70         if ( $@->diagset() eq 'ZOOM' && $@->code() == 10004 && !$in_retry ) {
  71             $self->log_debug('    upstream server lost connection, retrying');
  72             return $self->_start_search( $args, $num_to_prefetch, 1 );
  73         }
  74
  75         $self->_set_error_from_zoom( $args, $@ );
  76         $connection = undef;
  77     }
  78
  79     my $hits = $results ? $results->size() : -1;
  80     my $resultset = {
  81         database => $database,
  82         connection => $connection,
  83         results => $results,
  84         query => $args->{QUERY},
  85         hits => $hits
  86     };
  87
  88     return ( $resultset, $hits );
  89 }
  90
  91 =head3 fetch_record
  92
  93     my $record = $self->_fetch_record( $resultset, $args, $offset, $server->{num_to_prefetch} );
  94
  95 Fetch a record from Zebra. Caches records in session to avoid too many fetches.
  96
  97 =cut
  98
  99 sub fetch_record {
 100     my ( $self, $resultset, $args, $index, $num_to_prefetch ) = @_;
 101
 102     my $record;
 103
 104     eval {
 105         if ( !$resultset->{results}->record_immediate( $index ) ) {
 106             my $start = $num_to_prefetch ? int( $index / $num_to_prefetch ) * $num_to_prefetch : $index;
 107
 108             if ( $start + $num_to_prefetch >= $resultset->{results}->size() ) {
 109                 $num_to_prefetch = $resultset->{results}->size() - $start;
 110             }
 111
 112             $self->log_debug("    fetch uncached, fetching $num_to_prefetch records starting at $start");
 113
 114             $resultset->{results}->records( $start, $num_to_prefetch, 0 );
 115         }
 116
 117         $record = $resultset->{results}->record_immediate( $index )->raw();
 118     };
 119     if ($@) {
 120         die $@ if ( ref($@) ne 'ZOOM::Exception' );
 121         $self->_set_error_from_zoom( $args, $@ );
 122         return;
 123     } else {
 124         return $record;
 125     }
 126 }
 127
 128 =head3 close_handler
 129
 130 Callback that is called when a session is terminated
 131
 132 =cut
 133
 134 sub close_handler {
 135     my ( $self, $args ) = @_;
 136
 137     foreach my $resultset ( values %{ $self->{resultsets} } ) {
 138         $resultset->{results}->destroy();
 139     }
 140 }
 141
 142 =head3 _set_error_from_zoom
 143
 144     $self->_set_error_from_zoom( $args, $@ );
 145
 146 Log and set error code and diagnostic message from a ZOOM exception
 147
 148 =cut
 149
 150 sub _set_error_from_zoom {
 151     my ( $self, $args, $exception ) = @_;
 152
 153     $self->set_error( $args, $self->ERR_TEMPORARY_ERROR, 'Cannot connect to upstream server' );
 154     $self->log_error(
 155         "Zebra upstream error: " .
 156         $exception->message() . " (" .
 157         $exception->code() . ") " .
 158         ( $exception->addinfo() // '' ) . " " .
 159         $exception->diagset()
 160     );
 161 }
 162
 163 1;