Koha/opac/opac-rss.pl

158 lines
5.1 KiB
Perl
Executable file

#!/usr/bin/perl
# Copyright 2007 Paul POULAIN
#
# This file is part of Koha
#
# Koha is free software; you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version.
#
# Koha is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with
# Koha; if not, write to the Free Software Foundation, Inc., 59 Temple Place,
# Suite 330, Boston, MA 02111-1307 USA
use strict; # always use
use XML::RSS;
use Digest::MD5 qw(md5_base64);
use POSIX qw(ceil floor);
use Date::Calc qw(Today_and_Now Delta_YMDHMS);
use C4::Context;
use C4::Search;
use C4::Koha;
use C4::Biblio;
=head1 NAME
opac-rss.pl : script to have RSS feeds automatically on each OPAC search
=head1 SYNOPSIS
on each query (on OPAC), a link to this script is automatically added. The user can save it's queries as RSS feeds.
This script :
=over 4
- build the RDF file from the query
- save the RDF file in a opac/rss directory for caching : the RDF is calculated only once every 30mn, and the cache file name is calculated by a md5_base64 of the query (each user registering the same query will use the same cache : speed improvement)
- let the user specify it's query (q parameter : opac-rss.pl?q=ti:hugo)
- let the user specify the number of results returned (by default 20, but there are no limits : opac-rss.pl?q=ti:hugo&size=9999)
This script auto calculates the website URL
the RDF contains :
=over 4
- Koha: $query as RSS title
- Koha as subject
- LibraryName systempreference as RDF description and creator
- copyright currentyear
- biblio title as RSS "title" and biblio author as RSS description
=cut
# create a new CGI object
# not sure undef_params option is working, need to test
use CGI qw('-no_undef_params');
my $cgi = new CGI;
# the query to use
my $query = $cgi->param('q');
$query =~ s/:/=/g;
# the number of lines to retrieve
my $size = $cgi->param('size') || 50;
# the filename of the cached rdf file.
my $filename = md5_base64($query);
my $rss = new XML::RSS( version => '1.0' );
# the site URL
my $url = $cgi->url();
$url =~ s/opac-rss\.pl.*//;
$url =~ /(http:\/\/.*?)\//;
my $short_url = $1;
my $RDF_update_needed = 1;
my ( $year, $month, $day, $hour, $min, $sec ) = Today_and_Now();
if ( -e "rss/$filename" ) {
$rss->parsefile("rss/$filename");
# check if we have to rebuild the RSS feed (once every 30mn), or just return the actual rdf
my $rdf_stamp = $rss->{'channel'}->{'dc'}->{'date'};
$rdf_stamp =~ /(.*)-(.*)-(.*):(.*):(.*):(.*)/;
my (
$stamp_year, $stamp_month, $stamp_day,
$stamp_hour, $stamp_min, $stamp_sec
) = ( $1, $2, $3, $4, $5, $6 );
# if more than 30 mn since the last RDF update, rebuild the RDF. Otherwise, just return it
unless ( ( $year - $stamp_year > 0 )
or ( $month - $stamp_month > 0 )
or ( $day - $stamp_day > 0 )
or ( $hour - $stamp_hour > 0 )
or ( $min - $stamp_min > 30 ) )
{
$RDF_update_needed = 0;
}
}
if ($RDF_update_needed) {
# warn "RDF update in progress";
$rss->channel(
title => "Koha : $query",
description => C4::Context->preference("LibraryName"),
link => $short_url,
dc => {
date => "$year-$month-$day:$hour:$min:$sec",
subject => "Koha",
creator => C4::Context->preference("LibraryName"),
rights => "Copyright $year",
language => C4::Context->preference("opaclanguages"),
},
);
my $total; # the total results for the whole set
my ( $error, $marcresults ) = SimpleSearch($query);
my $hits = scalar @$marcresults;
$hits = $size if $hits > $size;
my @results;
for ( my $i = 0 ; $i < $hits ; $i++ ) {
my %resultsloop;
my $marcrecord = MARC::File::USMARC::decode( $marcresults->[$i] );
my $biblio = TransformMarcToKoha( C4::Context->dbh, $marcrecord, '' );
# check if the entry is already in the feed. Otherwise, pop the $line th line and add this new one.
my $already_in_feed = 0;
foreach ( @{ $rss->{'items'} } ) {
if ( $_->{'link'} =~ /biblionumber=$biblio->{'biblionumber'}/ ) {
$already_in_feed = 1;
}
}
unless ($already_in_feed) {
pop( @{ $rss->{'items'} } ) if ( @{ $rss->{'items'} } >= $size );
$rss->add_item(
title => $biblio->{'title'},
description => $biblio->{'author'},
link => "$url/opac-detail.pl?biblionumber="
. $biblio->{'biblionumber'},
mode => 'insert',
);
}
}
# save the rss feed.
$rss->save("rss/$filename");
}
print $cgi->header( -type => "application/rss+xml" );
print $rss->as_string;