##
#
# Copyright 2001, AllAfrica Global Media
#
# This file is part of XML::Comma
#
# XML::Comma 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
# any later version.
#
# This program 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.
#
# For more information about XML::Comma, point a web browser at
# http://xymbollab.com/tools/comma/, or read the tutorial included
# with the XML::Comma distribution at docs/guide.html
#
##
package XML::Comma::Storage::Location::Index_Only;
use XML::Comma::Util qw( dbg );
use strict;
# _index_name :
# _doctype :
sub new {
my ( $class, %arg ) = @_;
my $self = {};
bless ( $self, $class );
unless ( $arg{decl_pos} == 0 ) {
die "Index_Only Location module should be used only all by itself\n";
}
$self->{_index_name} = $arg{index_name} ||
die "Index_Only Location module needs an index_name argument\n";
$self->{_doctype} = $arg{store}->doctype();
my $index = XML::Comma::Def->read ( name=>$self->{_doctype} )
->get_index ( $self->{_index_name} ) ||
die "Index_Only error -- can't get index named $arg{index_name} for doctype '$arg{store}\n";
$index->element('doc_id_sql_type')
->set ( $index->sql_index_only_doc_id_type );
return ( $self );
}
sub MAJOR_NUMBER {
1;
}
sub decl_pos {
return undef;
}
sub make_id {
return ( 'COMMA_DB_SEQUENCE_SET', '' );
}
# mostly, we can just call index->update to do the work, here. the one
# complication is that we'll need to do a bit of cleanup -- setting
# the doc's storage_info fields correctly -- if this is a first-time
# write (or copy). we depend on the index insert code to generate a
# doc_id, but the insert code doesn't know enough to set all of the
# other storage_info fields, so it just sets doc_id and punts on the
# rest.
sub write {
my ( $self, $store, $location, $id, $block, $doc ) = @_;
my $need_to_set_sinfo = ( $id eq 'COMMA_DB_SEQUENCE_SET' );
my $index = $doc->def()->get_index ( $self->{_index_name} );
$index->update ( $doc );
if ( $need_to_set_sinfo ) {
$id = $doc->doc_id();
my $stype = $store->doctype();
my $sname = $store->name();
my $key = XML::Comma::Storage::Util->concat_key
( type => $stype, store => $sname, id => $id );
my $locked = XML::Comma->lock_singlet()->lock ( $key );
$doc->set_storage_info ( $store, undef, undef, $key );
};
}
sub location_from_id {
my ( $self, $store, $id, $location ) = @_;
return $id;
}
# FIX: recognize a special field in the index (perhaps 'comma_block')
# that is a pre-stored doc-block, which we will use in preference to
# calling _build_block_from_fields if possible.
sub read {
my ( $self, $store, $location, $id ) = @_;
my $index = XML::Comma::Def->read ( name => $self->{_doctype} )
->get_index ( $self->{_index_name} );
my $single = $index->single ( where_clause => "doc_id=$id" )
|| die ( "doc with id '$id' not found in index\n" );
return $self->_build_block_from_fields ( $index, $single );
}
sub _build_block_from_fields {
my ( $self, $index, $single ) = @_;
my $string = '<' . $self->{_doctype} . '>';
foreach my $field ( $index->elements('field') ) {
my $fname = $field->name();
$string .= "<$fname>" . $single->$fname . "</$fname>";
}
$string .= '</' . $self->{_doctype} . '>';
return $string;
}
sub erase {
my ( $self, $location, $doc ) = @_;
my $index = $doc->def()->get_index ( $self->{_index_name} );
$index->delete ( $doc );
}
sub next_location {
die
"Docs stored Index_Only cannot be iterated across, use indexing operations instead\n";
}
sub first_location {
die
"Docs stored Index_Only cannot be iterated across, use indexing operations instead\n";
}
sub last_location {
die
"Docs stored Index_Only cannot be iterated across, use indexing operations instead\n";
}
sub write_blob {
die "Docs stored Index_Only cannot store blobs\n";
}
sub read_blob {
die "Docs stored Index_Only cannot store blobs\n";
}
sub copy_to_blob {
die "Docs stored Index_Only cannot store blobs\n";
}
sub erase_blob {
die "Docs stored Index_Only cannot store blobs\n";
}
sub touch {
die "FIX: implement touch for Index_Only storage\n";
}
sub last_modified {
die "FIX: implement last-modified for Index_Only storage\n";
}
1;