C4/Z3950.pm

   1 package C4::Z3950;
   2
   3
   4 # Routines for handling Z39.50 lookups
   5
   6 # Koha library project  www.koha-community.org
   7
   8 # Licensed under the GPL
   9
  10 # Copyright 2000-2002 Katipo Communications
  11 #
  12 # This file is part of Koha.
  13 #
  14 # Koha is free software; you can redistribute it and/or modify it under the
  15 # terms of the GNU General Public License as published by the Free Software
  16 # Foundation; either version 2 of the License, or (at your option) any later
  17 # version.
  18 #
  19 # Koha is distributed in the hope that it will be useful, but WITHOUT ANY
  20 # WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  21 # A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  22 #
  23 # You should have received a copy of the GNU General Public License along
  24 # with Koha; if not, write to the Free Software Foundation, Inc.,
  25 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  26
  27 use strict;
  28 #use warnings; FIXME - Bug 2505
  29
  30 # standard or CPAN modules used
  31 use DBI;
  32
  33 # Koha modules used
  34 use C4::Input;
  35 use C4::Biblio;
  36
  37 use vars qw($VERSION @ISA @EXPORT);
  38
  39 BEGIN {
  40         # set the version for version checking
  41         $VERSION = 3.01;
  42         require Exporter;
  43         @ISA = qw(Exporter);
  44         @EXPORT = qw(
  45                 &getz3950servers
  46                 &z3950servername
  47                 &addz3950queue
  48                 &checkz3950searchdone
  49         );
  50 }
  51
  52 =head1 NAME
  53
  54 C4::Z3950 - Functions dealing with Z39.50 queries
  55
  56 =head1 SYNOPSIS
  57
  58   use C4::Z3950;
  59
  60 =head1 DESCRIPTION
  61
  62 This module contains functions for looking up Z39.50 servers, and for
  63 entering Z39.50 lookup requests.
  64
  65 =head1 FUNCTIONS
  66
  67 =over 2
  68
  69 =item getz3950servers
  70
  71   @servers= &getz3950servers(checked);
  72
  73 Returns the list of declared z3950 servers
  74
  75 C<$checked> should always be true (1) => returns only active servers.
  76 If 0 => returns all servers
  77
  78 =cut
  79
  80 sub getz3950servers {
  81         my ($checked) = @_;
  82         my $dbh = C4::Context->dbh;
  83         my $sth;
  84         if ($checked) {
  85                 $sth = $dbh->prepare("select * from z3950servers where checked=1");
  86         } else {
  87                 $sth = $dbh->prepare("select * from z3950servers");
  88         }
  89         my @result;
  90         while ( my ($host, $port, $db, $userid, $password,$servername) = $sth->fetchrow ) {
  91                 push @result, "$servername/$host\:$port/$db/$userid/$password";
  92         } # while
  93         return @result;
  94 }
  95
  96 =item z3950servername
  97
  98   $name = &z3950servername($dbh, $server_id, $default_name);
  99
 100 Looks up a Z39.50 server by ID number, and returns its full name. If
 101 the server is not found, returns C<$default_name>.
 102
 103 C<$server_id> is the Z39.50 server ID to look up.
 104
 105 C<$dbh> is ignored.
 106
 107 =cut
 108
 109 #'
 110
 111 sub z3950servername {
 112         # inputs
 113         my ($srvid,             # server id number
 114                 $default,)=@_;
 115         # return
 116         my $longname;
 117         #----
 118
 119         my $dbh = C4::Context->dbh;
 120
 121         my $sti=$dbh->prepare("select name from z3950servers where id=?");
 122
 123         $sti->execute($srvid);
 124         if ( ! $sti->err ) {
 125                 ($longname)=$sti->fetchrow;
 126         }
 127         if (! $longname) {
 128                 $longname="$default";
 129         }
 130                 return $longname;
 131 } # sub z3950servername
 132
 133 #---------------------------------------
 134
 135 =item addz3950queue
 136
 137   $errmsg = &addz3950queue($query, $type, $request_id, @servers);
 138
 139 Adds a Z39.50 search query for the Z39.50 server to look up.
 140
 141 C<$query> is the term to search for.
 142
 143 C<$type> is the query type, e.g. C<isbn>, C<lccn>, etc.
 144
 145 C<$request_id> is a unique string that will identify this query.
 146
 147 C<@servers> is a list of servers to query (obviously, this can be
 148 given either as an array, or as a list of scalars). Each element may
 149 be either a Z39.50 server ID from the z3950server table of the Koha
 150 database, the string C<DEFAULT> or C<CHECKED>, or a complete server
 151 specification containing a colon.
 152
 153 C<DEFAULT> and C<CHECKED> are synonymous, and refer to those servers
 154 in the z3950servers table whose 'checked' field is set and non-NULL.
 155
 156 Once the query has been submitted to the Z39.50 daemon,
 157 C<&addz3950queue> sends a SIGHUP to the daemon to tell it to process
 158 this new request.
 159
 160 C<&addz3950queue> returns an error message. If it was successful, the
 161 error message is the empty string.
 162
 163 =cut
 164
 165 #'
 166 sub addz3950queue {
 167         use strict;
 168         # input
 169         my (
 170                 $query,         # value to look up
 171                 $type,                  # type of value ("isbn", "lccn", "title", "author", "keyword")
 172                 $requestid,     # Unique value to prevent duplicate searches from multiple HTML form submits
 173                 @z3950list,     # list of z3950 servers to query
 174         )=@_;
 175         # Returns:
 176         my $error;
 177
 178         my (
 179                 $sth,
 180                 @serverlist,
 181                 $server,
 182                 $failed,
 183                 $servername,
 184         );
 185
 186         # FIXME - Should be configurable, probably in /etc/koha.conf.
 187         my $pidfile='/var/log/koha/processz3950queue.pid';
 188
 189         $error="";
 190
 191         my $dbh = C4::Context->dbh;
 192         # list of servers: entry can be a fully qualified URL-type entry
 193         #   or simply just a server ID number.
 194         foreach $server (@z3950list) {
 195                 if ($server =~ /:/ ) {
 196                         push @serverlist, $server;
 197                 } elsif ($server eq 'DEFAULT' || $server eq 'CHECKED' ) {
 198                         $sth=$dbh->prepare("select host,port,db,userid,password ,name,syntax from z3950servers where checked <> 0 ");
 199                         $sth->execute;
 200                         while ( my ($host, $port, $db, $userid, $password,$servername,$syntax) = $sth->fetchrow ) {
 201                                 push @serverlist, "$servername/$host\:$port/$db/$userid/$password/$syntax";
 202                         } # while
 203                 } else {
 204                         $sth=$dbh->prepare("select host,port,db,userid,password,syntax from z3950servers where id=? ");
 205                         $sth->execute($server);
 206                         my ($host, $port, $db, $userid, $password,$syntax) = $sth->fetchrow;
 207                         push @serverlist, "$server/$host\:$port/$db/$userid/$password/$syntax";
 208                 }
 209         }
 210
 211         my $serverlist='';
 212
 213         $serverlist = join("|", @serverlist);
 214 #       chop $serverlist;
 215
 216         # FIXME - Is this test supposed to test whether @serverlist is
 217         # empty? If so, then a) there are better ways to do that in
 218         # Perl (e.g., "if (@serverlist eq ())"), and b) it doesn't
 219         # work anyway, since it checks whether $serverlist is composed
 220         # of one or more spaces, which is never the case, not even
 221         # when there are 0 or 1 elements in @serverlist.
 222         if ( $serverlist !~ /^ +$/ ) {
 223                 # Don't allow reinsertion of the same request identifier.
 224                 $sth=$dbh->prepare("select identifier from z3950queue
 225                         where identifier=?");
 226                 $sth->execute($requestid);
 227                 if ( ! $sth->rows) {
 228                         $sth=$dbh->prepare("insert into z3950queue (term,type,servers, identifier) values (?, ?, ?, ?)");
 229                         $sth->execute($query, $type, $serverlist, $requestid);
 230                         if ( -r $pidfile ) {
 231                                 # FIXME - Perl is good at opening files. No need to
 232                                 # spawn a separate 'cat' process.
 233                                 my $pid=`cat $pidfile`;
 234                                 chomp $pid;
 235                                 # Kill -HUP the Z39.50 daemon to tell it to process
 236                                 # this query.
 237                                 my $processcount=kill 1, $pid;
 238                                 if ($processcount==0) {
 239                                         $error.="Z39.50 search daemon error: no process signalled. ";
 240                                 }
 241                         } else {
 242                                 # FIXME - Error-checking like this should go close
 243                                 # to the test.
 244                                 $error.="No Z39.50 search daemon running: no file $pidfile. ";
 245                         } # if $pidfile
 246                 } else {
 247                         # FIXME - Error-checking like this should go close
 248                         # to the test.
 249                         $error.="Duplicate request ID $requestid. ";
 250                 } # if rows
 251         } else {
 252                 # FIXME - Error-checking like this should go close to the
 253                 # test. I.e.,
 254                 #       return "No Z39.50 search servers specified. "
 255                 #               if @serverlist eq ();
 256
 257                 # server list is empty
 258                 $error.="No Z39.50 search servers specified. ";
 259         } # if serverlist empty
 260
 261         return $error;
 262
 263 } # sub addz3950queue
 264
 265 =item &checkz3950searchdone
 266
 267   $numberpending= &     &checkz3950searchdone($random);
 268
 269 Returns the number of pending z3950 requests
 270
 271 C<$random> is the random z3950 query number.
 272
 273 =cut
 274
 275 sub checkz3950searchdone {
 276         my ($z3950random) = @_;
 277         my $dbh = C4::Context->dbh;
 278         # first, check that the deamon already created the requests...
 279         my $sth = $dbh->prepare("select count(*) from z3950queue,z3950results where z3950queue.id = z3950results.queryid and z3950queue.identifier=?");
 280         $sth->execute($z3950random);
 281         my ($result) = $sth->fetchrow;
 282         if ($result eq 0) { # search not yet begun => should be searches to do !
 283                 return "??";
 284         }
 285         # second, count pending requests
 286         $sth = $dbh->prepare("select count(*) from z3950queue,z3950results where z3950queue.id = z3950results.queryid and z3950results.enddate is null and z3950queue.identifier=?");
 287         $sth->execute($z3950random);
 288         ($result) = $sth->fetchrow;
 289         return $result;
 290 }
 291
 292 1;
 293 __END__
 294
 295 =back
 296
 297 =head1 AUTHOR
 298
 299 Koha Development Team <http://koha-community.org/>
 300
 301 =cut