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# -*- Mode: Cperl -*- |
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# Table.pm -- |
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# ITIID : $ITI$ $Header $__Header$ |
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# Author : Ulrich Pfeifer |
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# Created On : Thu Aug 8 13:05:10 1996 |
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# Last Modified By: Ulrich Pfeifer |
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# Last Modified On: Sun Nov 12 17:51:56 2000 |
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# Language : CPerl |
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# Update Count : 148 |
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# Status : Unknown, Use with caution! |
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# |
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# Copyright (c) 1996-1997, Ulrich Pfeifer |
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# |
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|
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=head1 NAME |
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|
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WAIT::Table -- Module for maintaining Tables / Relations |
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|
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=head1 SYNOPSIS |
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|
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require WAIT::Table; |
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|
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=head1 DESCRIPTION |
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|
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=cut |
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|
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package WAIT::Table; |
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|
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use WAIT::Table::Handle (); |
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require WAIT::Parse::Base; |
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|
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use strict; |
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use Carp; |
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# use autouse Carp => qw( croak($) ); |
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use DB_File; |
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use Fcntl; |
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use LockFile::Simple (); |
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|
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my $USE_RECNO = 0; |
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|
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=head2 Creating a Table. |
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|
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The constructor WAIT::Table-E<gt>new is normally called via the |
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create_table method of a database handle. This is not enforced, but |
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creating a table does not make any sense unless the table is |
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registered by the database because the latter implements persistence |
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of the meta data. Registering is done automatically by letting the |
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database handle the creation of a table. |
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|
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my $db = WAIT::Database->create(name => 'sample'); |
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my $tb = $db->create_table(name => 'test', |
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access => $access, |
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layout => $layout, |
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attr => ['docid', 'headline'], |
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); |
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|
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The constructor returns a handle for the table. This handle is hidden by the |
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table module, to prevent direct access if called via Table. |
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|
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=over 10 |
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|
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=item C<access> => I<accessobj> |
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|
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A reference to an access object for the external parts (attributes) of |
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tuples. As you may remember, the WAIT System does not enforce that |
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objects are completely stored inside the system to avoid duplication. |
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There is no (strong) point in storing all your HTML documents inside |
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the system when indexing your WWW-Server. |
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|
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The access object is designed to work like as a tied hash. You pass |
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the refernce to the object, not the tied hash though. An example |
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implementation of an access class that works for manpages is |
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WAIT::Document::Nroff. |
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|
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The implementation needs to take into account that WAIT will keep this |
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object in a Data::Dumper or Storable database and re-use it when sman |
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is run. So it is not good enough if we can produce the index with it |
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now, when we create or actively access the table, WAIT also must be |
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able to retrieve documents on its own, when we are in a different |
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context. This happens specifically in a retrieval. To get this working |
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seemlessly, the access-defining class must implement a close method. |
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This method will be called before the Data::Dumper dump takes place. |
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In that moment the access-defining class must get rid of all data |
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structures that cannot be reconstructed via the Data::Dumper dump, |
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such as database handles or C pointers. |
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|
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=item C<file> => I<fname> |
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|
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The filename of the records file. Files for indexes will have I<fname> |
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as prefix. I<Mandatory>, but usually taken care of by the |
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WAIT::Database handle when the constructor is called via |
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WAIT::Database::create_table(). |
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|
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=item C<name> => I<name> |
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|
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The name of this table. I<Mandatory> |
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|
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=item C<attr> => [ I<attr> ... ] |
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|
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A reference to an array of attribute names. WAIT will keep the |
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contents of these attributes in its table. I<Mandatory> |
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|
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=item C<djk> => [ I<attr> ... ] |
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|
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A reference to an array of attribute names which make up the |
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I<disjointness key>. Don't think about it - it's of no use yet; |
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|
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=item C<layout> => I<layoutobj> |
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|
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A reference to an external parser object. Defaults to a new instance |
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of C<WAIT::Parse::Base>. For an example implementation see |
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WAIT::Parse::Nroff. A layout class can be implemented as a singleton |
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class if you so like. |
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|
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=item C<keyset> => I<keyset> |
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|
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The set of attributes needed to identify a record. Defaults to all |
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attributes. |
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|
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=item C<invindex> => I<inverted index> |
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|
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A reference to an anon array defining attributes of each record that |
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need to be indexed. See the source of smakewhatis for how to set this |
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up. |
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|
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=back |
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|
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=cut |
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|
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sub new { |
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my $type = shift; |
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my %parm = @_; |
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my $self = {}; |
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|
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# Check for mandatory attrs early |
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$self->{name} = $parm{name} or croak "No name specified"; |
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$self->{attr} = $parm{attr} or croak "No attributes specified"; |
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|
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# Do that before we eventually add '_weight' to attributes. |
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$self->{keyset} = $parm{keyset} || [[@{$parm{attr}}]]; |
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|
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$self->{mode} = O_CREAT | O_RDWR; |
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|
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# Determine and set up subclass |
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$type = ref($type) || $type; |
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if (defined $parm{djk}) { |
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if (@{$parm{djk}} == @{$parm{attr}}) { |
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# All attributes in DK (sloppy test here!) |
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$type .= '::Independent'; |
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require WAIT::Table::Independent; |
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} else { |
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$type .= '::Disjoint'; |
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require WAIT::Table::Disjoint; |
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} |
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# Add '_weight' to attributes |
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my %attr; |
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@attr{@{$parm{attr}}} = (1) x @{$parm{attr}}; |
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unshift @{$parm{attr}}, '_weight' unless $attr{'_weight'}; |
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} |
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|
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$self->{file} = $parm{file} or croak "No file specified"; |
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if (-d $self->{file}){ |
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warn "Warning: Directory '$self->{file}' already exists\n"; |
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} elsif (!mkdir($self->{file}, 0775)) { |
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croak "Could not 'mkdir $self->{file}': $!\n"; |
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} |
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|
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$self->{djk} = $parm{djk} if defined $parm{djk}; |
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$self->{layout} = $parm{layout} || new WAIT::Parse::Base; |
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$self->{access} = $parm{access} if defined $parm{access}; |
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$self->{nextk} = 1; # next record to insert; first record unused |
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$self->{deleted} = {}; # no deleted records yet |
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$self->{indexes} = {}; |
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|
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bless $self, $type; |
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|
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# Checking for readers is not necessary, but let's go with the |
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# generic method. |
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$self->getlock(O_RDWR|O_CREAT); # dies when failing |
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|
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# Call create_index() and create_index() for compatibility |
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for (@{$self->{keyset}||[]}) { |
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#carp "Specification of indexes at table create time is deprecated"; |
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$self->create_index(@$_); |
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} |
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while (@{$parm{invindex}||[]}) { |
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# carp "Specification of inverted indexes at table create time is deprecated"; |
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my $att = shift @{$parm{invindex}}; |
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my @spec = @{shift @{$parm{invindex}}}; |
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my @opt; |
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|
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if (ref($spec[0])) { |
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carp "Secondary pipelines are deprecated\n"; |
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@opt = %{shift @spec}; |
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} |
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$self->create_inverted_index(attribute => $att, pipeline => \@spec, @opt); |
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} |
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|
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$self; |
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# end of backwarn compatibility stuff |
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} |
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|
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=head2 Creating an index |
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|
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$tb->create_index('docid'); |
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|
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=item C<create_index> |
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|
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must be called with a list of attributes. This must be a subset of the |
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attributes specified when the table was created. Currently this |
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method must be called before the first tuple is inserted in the |
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table! |
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|
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=cut |
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|
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sub create_index { |
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my $self= shift; |
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|
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croak "Cannot create index for table aready populated" |
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if $self->{nextk} > 1; |
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|
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require WAIT::Index; |
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|
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my $name = join '-', @_; |
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$self->{indexes}->{$name} = |
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new WAIT::Index file => $self->{file}.'/'.$name, attr => $_; |
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} |
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|
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=head2 Creating an inverted index |
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|
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$tb->create_inverted_index |
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(attribute => 'au', |
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pipeline => ['detex', 'isotr', 'isolc', 'split2', 'stop'], |
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predicate => 'plain', |
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); |
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|
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=over 5 |
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|
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=item C<attribute> |
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|
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The attribute to build the index on. This attribute may not be in the |
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set attributes specified when the table was created. |
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|
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=item C<pipeline> |
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|
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A piplines specification is a reference to an array of method names |
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(from package C<WAIT::Filter>) which are to be applied in sequence to |
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the contents of the named attribute. The attribute name may not be in |
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the attribute list. |
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|
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=item C<predicate> |
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|
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An indication which predicate the index implements. This may be |
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e.g. 'plain', 'stemming' or 'soundex'. The indicator will be used for |
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query processing. Currently there is no standard set of predicate |
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names. The predicate defaults to the last member of the pipeline if |
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omitted. |
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|
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=back |
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|
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Currently this method must be called before the first tuple is |
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inserted in the table! |
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|
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=cut |
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|
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sub create_inverted_index { |
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my $self = shift; |
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my %parm = @_; |
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|
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croak "No attribute specified" unless $parm{attribute}; |
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croak "No pipeline specified" unless $parm{pipeline}; |
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|
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$parm{predicate} ||= $parm{pipeline}->[-1]; |
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|
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croak "Cannot create index for table aready populated" |
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if $self->{nextk} > 1; |
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|
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require WAIT::InvertedIndex; |
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|
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# backward compatibility stuff |
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my %opt = %parm; |
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for (qw(attribute pipeline predicate)) { |
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delete $opt{$_}; |
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} |
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|
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my $name = join '_', ($parm{attribute}, @{$parm{pipeline}}); |
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my $idx = new WAIT::InvertedIndex(file => $self->{file}.'/'.$name, |
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filter => [@{$parm{pipeline}}], # clone |
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name => $name, |
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attr => $parm{attribute}, |
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%opt, # backward compatibility stuff |
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); |
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# We will have to use $parm{predicate} here |
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push @{$self->{inverted}->{$parm{attribute}}}, $idx; |
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} |
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|
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sub dir { |
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$_[0]->{file}; |
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} |
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|
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=head2 C<$tb-E<gt>layout> |
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|
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Returns the reference to the associated parser object. |
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|
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=cut |
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|
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sub layout { $_[0]->{layout} } |
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|
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=head2 C<$tb-E<gt>fields> |
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|
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Returns the array of attribute names. |
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|
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=cut |
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|
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|
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sub fields { keys %{$_[0]->{inverted}}} |
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|
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=head2 C<$tb-E<gt>drop> |
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|
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Must be called via C<WAIT::Database::drop_table> |
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|
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=cut |
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|
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sub drop { |
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my $self = shift; |
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|
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unless ($self->{write_lock}){ |
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warn "Cannot drop table without write lock. Nothing done"; |
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return; |
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} |
331 |
|
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if ((caller)[0] eq 'WAIT::Database') { # database knows about this |
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$self->close; # just make sure |
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|
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my $file = $self->{file}; |
336 |
|
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for (values %{$self->{indexes}}) { |
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$_->drop; |
339 |
} |
340 |
unlink "$file/records"; |
341 |
rmdir "$file/read" or warn "Could not rmdir '$file/read'"; |
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|
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# $self->unlock; |
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! (!-e $file or rmdir $file); |
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} else { |
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croak ref($self)."::drop called directly"; |
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} |
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} |
349 |
|
350 |
sub mrequire ($) { |
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my $module = shift; |
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|
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$module =~ s{::}{/}g; |
354 |
$module .= '.pm'; |
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require $module; |
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} |
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|
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sub open { |
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my $self = shift; |
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my $file = $self->{file} . '/records'; |
361 |
|
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mrequire ref($self); # that's tricky eh? |
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if (defined $self->{'layout'}) { |
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mrequire ref($self->{'layout'}); |
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} |
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if (defined $self->{'access'}) { |
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mrequire ref($self->{'access'}); |
368 |
} |
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if (exists $self->{indexes}) { |
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require WAIT::Index; |
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for (values %{$self->{indexes}}) { |
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$_->{mode} = $self->{mode}; |
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} |
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} |
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if (exists $self->{inverted}) { |
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my ($att, $idx); |
377 |
for $att (keys %{$self->{inverted}}) { |
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for $idx (@{$self->{inverted}->{$att}}) { |
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$idx->{mode} = $self->{mode}; |
380 |
} |
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} |
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require WAIT::InvertedIndex; |
383 |
} |
384 |
unless (defined $self->{dbh}) { |
385 |
if ($USE_RECNO) { |
386 |
$self->{dbh} = tie(@{$self->{db}}, 'DB_File', $file, |
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$self->{mode}, 0664, $DB_RECNO); |
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} else { |
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$self->{dbh} = |
390 |
tie(%{$self->{db}}, 'DB_File', $file, |
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$self->{mode}, 0664, $DB_BTREE); |
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} |
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} |
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|
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$self->getlock($self->{mode}); |
396 |
|
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$self; |
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} |
399 |
|
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sub fetch_extern { |
401 |
my $self = shift; |
402 |
|
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# print "#@_", $self->{'access'}->{Mode}, "\n"; # DEBUGGING? |
404 |
if (exists $self->{'access'}) { |
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mrequire ref($self->{'access'}); |
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$self->{'access'}->FETCH(@_); |
407 |
} |
408 |
} |
409 |
|
410 |
sub fetch_extern_by_id { |
411 |
my $self = shift; |
412 |
|
413 |
$self->fetch_extern($self->fetch(@_)); |
414 |
} |
415 |
|
416 |
sub _find_index { |
417 |
my $self = shift; |
418 |
my (@att) = @_; |
419 |
my %att; |
420 |
my $name; |
421 |
|
422 |
@att{@att} = @att; |
423 |
|
424 |
KEY: for $name (keys %{$self->{indexes}}) { |
425 |
my @iat = split /-/, $name; |
426 |
for (@iat) { |
427 |
next KEY unless exists $att{$_}; |
428 |
} |
429 |
return $self->{indexes}->{$name}; |
430 |
} |
431 |
return undef; |
432 |
} |
433 |
|
434 |
sub have { |
435 |
my $self = shift; |
436 |
my %parm = @_; |
437 |
|
438 |
my $index = $self->_find_index(keys %parm) or return; # no index-no have |
439 |
|
440 |
defined $self->{db} or $self->open; |
441 |
return $index->have(@_); |
442 |
} |
443 |
|
444 |
sub insert { |
445 |
my $self = shift; |
446 |
my %parm = @_; |
447 |
|
448 |
defined $self->{db} or $self->open; |
449 |
|
450 |
# We should move all writing methods to a subclass to check only once |
451 |
$self->{mode} & O_RDWR or croak "Cannot insert into table opened in RD_ONLY mode"; |
452 |
|
453 |
my $tuple = join($;, map($parm{$_} || '', @{$self->{attr}})); |
454 |
my $key; |
455 |
my @deleted = keys %{$self->{deleted}}; |
456 |
my $gotkey = 0; |
457 |
|
458 |
if (@deleted) { |
459 |
$key = pop @deleted; |
460 |
delete $self->{deleted}->{$key}; |
461 |
# Sanity check |
462 |
if ($key && $key>0) { |
463 |
$gotkey=1; |
464 |
} else { |
465 |
warn(sprintf("WAIT database inconsistency during insert ". |
466 |
"key[%s]: Please rebuild index\n", |
467 |
$key |
468 |
)); |
469 |
} |
470 |
} |
471 |
unless ($gotkey) { |
472 |
$key = $self->{nextk}++; |
473 |
} |
474 |
if ($USE_RECNO) { |
475 |
$self->{db}->[$key] = $tuple; |
476 |
} else { |
477 |
$self->{db}->{$key} = $tuple; |
478 |
} |
479 |
for (values %{$self->{indexes}}) { |
480 |
unless ($_->insert($key, %parm)) { |
481 |
# duplicate key, undo changes |
482 |
if ($key == $self->{nextk}-1) { |
483 |
$self->{nextk}--; |
484 |
} else { |
485 |
# warn "setting key[$key] deleted during insert"; |
486 |
$self->{deleted}->{$key}=1; |
487 |
} |
488 |
my $idx; |
489 |
for $idx (values %{$self->{indexes}}) { |
490 |
last if $idx eq $_; |
491 |
$idx->remove($key, %parm); |
492 |
} |
493 |
return undef; |
494 |
} |
495 |
} |
496 |
if (defined $self->{inverted}) { |
497 |
my $att; |
498 |
for $att (keys %{$self->{inverted}}) { |
499 |
if (defined $parm{$att}) { |
500 |
map $_->insert($key, $parm{$att}), @{$self->{inverted}->{$att}}; |
501 |
#map $_->sync, @{$self->{inverted}->{$att}} |
502 |
} |
503 |
} |
504 |
} |
505 |
$key |
506 |
} |
507 |
|
508 |
sub sync { |
509 |
my $self = shift; |
510 |
|
511 |
for (values %{$self->{indexes}}) { |
512 |
map $_->sync, $_; |
513 |
} |
514 |
if (defined $self->{inverted}) { |
515 |
my $att; |
516 |
for $att (keys %{$self->{inverted}}) { |
517 |
map $_->sync, @{$self->{inverted}->{$att}} |
518 |
} |
519 |
} |
520 |
} |
521 |
|
522 |
sub fetch { |
523 |
my $self = shift; |
524 |
my $key = shift; |
525 |
|
526 |
return () if exists $self->{deleted}->{$key}; |
527 |
|
528 |
defined $self->{db} or $self->open; |
529 |
if ($USE_RECNO) { |
530 |
$self->unpack($self->{db}->[$key]); |
531 |
} else { |
532 |
$self->unpack($self->{db}->{$key}); |
533 |
} |
534 |
} |
535 |
|
536 |
sub delete_by_key { |
537 |
my $self = shift; |
538 |
my $key = shift; |
539 |
|
540 |
unless ($key) { |
541 |
Carp::cluck "Warning: delete_by_key called without key. Looks like a bug in WAIT?"; |
542 |
return; |
543 |
} |
544 |
|
545 |
return $self->{deleted}->{$key} if defined $self->{deleted}->{$key}; |
546 |
my %tuple = $self->fetch($key); |
547 |
for (values %{$self->{indexes}}) { |
548 |
$_->delete($key, %tuple); |
549 |
} |
550 |
if (defined $self->{inverted}) { |
551 |
# User *must* provide the full record for this or the entries |
552 |
# in the inverted index will not be removed |
553 |
%tuple = (%tuple, @_); |
554 |
my $att; |
555 |
for $att (keys %{$self->{inverted}}) { |
556 |
if (defined $tuple{$att}) { |
557 |
map $_->delete($key, $tuple{$att}), @{$self->{inverted}->{$att}} |
558 |
} |
559 |
} |
560 |
} |
561 |
# warn "setting key[$key] deleted during delete_by_key"; |
562 |
++$self->{deleted}->{$key}; |
563 |
} |
564 |
|
565 |
sub delete { |
566 |
my $self = shift; |
567 |
my $tkey = $self->have(@_); |
568 |
# warn "tkey[$tkey]\@_[@_]"; |
569 |
defined $tkey && $self->delete_by_key($tkey, @_); |
570 |
} |
571 |
|
572 |
sub unpack { |
573 |
my($self, $tuple) = @_; |
574 |
|
575 |
unless (defined $tuple){ |
576 |
# require Carp; # unfortunately gives us "bizarre copy...." :-((((( |
577 |
warn("Debug: somebody called unpack without argument tuple!"); |
578 |
return; |
579 |
} |
580 |
|
581 |
my $att; |
582 |
my @result; |
583 |
my @tuple = split /$;/, $tuple; |
584 |
|
585 |
for $att (@{$self->{attr}}) { |
586 |
push @result, $att, shift @tuple; |
587 |
} |
588 |
@result; |
589 |
} |
590 |
|
591 |
sub set { |
592 |
my ($self, $iattr, $value) = @_; |
593 |
|
594 |
unless ($self->{write_lock}){ |
595 |
warn "Cannot set iattr[$iattr] without write lock. Nothing done"; |
596 |
return; |
597 |
} |
598 |
for my $att (keys %{$self->{inverted}}) { |
599 |
if ($] > 5.003) { # avoid bug in perl up to 5.003_05 |
600 |
my $idx; |
601 |
for $idx (@{$self->{inverted}->{$att}}) { |
602 |
$idx->set($iattr, $value); |
603 |
} |
604 |
} else { |
605 |
map $_->set($iattr, $value), @{$self->{inverted}->{$att}}; |
606 |
} |
607 |
} |
608 |
|
609 |
1; |
610 |
} |
611 |
|
612 |
sub close { |
613 |
my $self = shift; |
614 |
|
615 |
if (exists $self->{'access'}) { |
616 |
eval {$self->{'access'}->close}; # dont bother if not opened |
617 |
} |
618 |
if ($WAIT::Index::VERSION) { |
619 |
for (values %{$self->{indexes}}) { |
620 |
$_->close(); |
621 |
} |
622 |
} |
623 |
if (defined $self->{inverted} && $WAIT::InvertedIndex::VERSION) { |
624 |
# require WAIT::InvertedIndex; Uli: we can avoid closing indexes: |
625 |
# if WAIT::InvertedIndex has not been loaded, they cannot have |
626 |
# been altered so far |
627 |
my $att; |
628 |
for $att (keys %{$self->{inverted}}) { |
629 |
if ($] > 5.003) { # avoid bug in perl up to 5.003_05 |
630 |
my $idx; |
631 |
for $idx (@{$self->{inverted}->{$att}}) { |
632 |
$idx->close; |
633 |
} |
634 |
} else { |
635 |
map $_->close(), @{$self->{inverted}->{$att}}; |
636 |
} |
637 |
} |
638 |
} |
639 |
if ($self->{dbh}) { |
640 |
delete $self->{dbh}; |
641 |
|
642 |
if ($USE_RECNO) { |
643 |
untie @{$self->{db}}; |
644 |
} else { |
645 |
untie %{$self->{db}}; |
646 |
} |
647 |
delete $self->{db}; |
648 |
} |
649 |
|
650 |
$self->unlock; |
651 |
|
652 |
1; |
653 |
} |
654 |
|
655 |
# Locking |
656 |
# |
657 |
# We allow multiple readers to coexists. But write access excludes |
658 |
# all read access and vice versa. In practice read access on tables |
659 |
# open for writing will mostly work ;-) |
660 |
|
661 |
# If a "write" lock is requested, an existing "read" lock will be |
662 |
# released. If a "read" lock ist requested, an existing "write" lock |
663 |
# will be released. Requiring a lock already hold has no effect. |
664 |
|
665 |
sub getlock { |
666 |
my ($self, $mode) = @_; |
667 |
|
668 |
my $lockmgr = LockFile::Simple->make(-autoclean => 1); |
669 |
my $file = $self->{file} . '/records'; |
670 |
my $lockdir = $self->{file} . '/read'; |
671 |
|
672 |
unless (-d $lockdir) { |
673 |
mkdir $lockdir, 0755 or die "Could not mkdir $lockdir: $!"; |
674 |
} |
675 |
|
676 |
if ($mode & O_RDWR) { # Get a write lock. Release it again |
677 |
# and die if there is any valid |
678 |
# readers. |
679 |
|
680 |
# Have a write lock already |
681 |
return $self if $self->{write_lock}; |
682 |
|
683 |
if ($self->{read_lock}) { # We are a becoming a writer now. So |
684 |
# we release the read lock to avoid |
685 |
# blocking ourselves. |
686 |
$self->{read_lock}->release; |
687 |
delete $self->{read_lock}; |
688 |
} |
689 |
|
690 |
# Get the preliminary write lock |
691 |
$self->{write_lock} = $lockmgr->lock($self->{file} . '/write') |
692 |
or die "Can't lock '$self->{file}/write'"; |
693 |
|
694 |
# If we actually want to write we must check if there are any |
695 |
# readers. The write lock is confirmed if wen cannot find any |
696 |
# valid readers. |
697 |
|
698 |
local *DIR; |
699 |
opendir DIR, $lockdir or |
700 |
die "Could not opendir '$lockdir': $!"; |
701 |
for my $lockfile (grep { -f "$lockdir/$_" } readdir DIR) { |
702 |
# Check if the locks are still valid. Since we are protected by |
703 |
# a write lock, we could use a plain file. But we want to use |
704 |
# the stale testing from LockFile::Simple. |
705 |
if (my $lck = $lockmgr->trylock("$lockdir/$lockfile")) { |
706 |
warn "Removing stale lockfile '$lockdir/$lockfile'"; |
707 |
$lck->release; |
708 |
} else { # Found an active reader, rats! |
709 |
$self->{write_lock}->release; |
710 |
die "Cannot write table '$file' while it's in use"; |
711 |
} |
712 |
} |
713 |
closedir DIR; |
714 |
} else { |
715 |
# Have a read lock already |
716 |
return $self if $self->{read_lock}; |
717 |
|
718 |
# Get the preliminary write lock to protect the directory |
719 |
# operations. If we already have a write lock, it will go. |
720 |
|
721 |
$self->{write_lock} ||= $lockmgr->lock($self->{file} . '/write') |
722 |
or die "Can't lock '$self->{file}/write'"; |
723 |
|
724 |
# Find a new read slot. Maybe the plain file would be better? |
725 |
my $id = time; |
726 |
while (-f "$lockdir/$id.lock") { # here assume ".lock" format! |
727 |
$id++; |
728 |
} |
729 |
|
730 |
$self->{read_lock} = $lockmgr->lock("$lockdir/$id") |
731 |
or die "Can't lock '$lockdir/$id'"; |
732 |
|
733 |
# We are a reader now. So we release the write lock |
734 |
$self->{write_lock}->release; |
735 |
delete $self->{write_lock}; |
736 |
} |
737 |
return $self; |
738 |
} |
739 |
|
740 |
sub unlock { |
741 |
my $self = shift; |
742 |
|
743 |
# Either we have a read or a write lock (or we close the table already) |
744 |
# unless ($self->{read_lock} || $self->{write_lock}) { |
745 |
# warn "WAIT::Table::unlock: Table aparently hold's no lock" |
746 |
# } |
747 |
if ($self->{write_lock}) { |
748 |
$self->{write_lock}->release(); |
749 |
delete $self->{write_lock}; |
750 |
} |
751 |
if ($self->{read_lock}) { |
752 |
$self->{read_lock}->release(); |
753 |
delete $self->{read_lock}; |
754 |
} |
755 |
|
756 |
} |
757 |
|
758 |
sub DESTROY { |
759 |
my $self = shift; |
760 |
|
761 |
if ($self->{write_lock} || $self->{read_lock}) { |
762 |
warn "Table handle destroyed without closing it first"; |
763 |
$self->unlock; |
764 |
} |
765 |
} |
766 |
|
767 |
sub open_scan { |
768 |
my $self = shift; |
769 |
my $code = shift; |
770 |
|
771 |
$self->{dbh} or $self->open; |
772 |
require WAIT::Scan; |
773 |
new WAIT::Scan $self, $self->{nextk}-1, $code; |
774 |
} |
775 |
|
776 |
sub open_index_scan { |
777 |
my $self = shift; |
778 |
my $attr = shift; |
779 |
my $code = shift; |
780 |
my $name = join '-', @$attr; |
781 |
|
782 |
if (defined $self->{indexes}->{$name}) { |
783 |
$self->{indexes}->{$name}->open_scan($code); |
784 |
} else { |
785 |
croak "No such index '$name'"; |
786 |
} |
787 |
} |
788 |
|
789 |
eval {sub WAIT::Query::Raw::new} unless defined \&WAIT::Query::Raw::new; |
790 |
|
791 |
sub prefix { |
792 |
my ($self , $attr, $prefix) = @_; |
793 |
my %result; |
794 |
|
795 |
defined $self->{db} or $self->open; # require layout |
796 |
|
797 |
for (@{$self->{inverted}->{$attr}}) { |
798 |
my $result = $_->prefix($prefix); |
799 |
if (defined $result) { |
800 |
$result{$_->name} = $result; |
801 |
} |
802 |
} |
803 |
bless \%result, 'WAIT::Query::Raw'; |
804 |
} |
805 |
|
806 |
sub intervall { |
807 |
my ($self, $attr, $lb, $ub) = @_; |
808 |
my %result; |
809 |
|
810 |
defined $self->{db} or $self->open; # require layout |
811 |
|
812 |
for (@{$self->{inverted}->{$attr}}) { |
813 |
my $result = $_->intervall($lb, $ub); |
814 |
if (defined $result) { |
815 |
$result{$_->name} = $result; |
816 |
} |
817 |
} |
818 |
bless \%result, 'WAIT::Query::Raw'; |
819 |
} |
820 |
|
821 |
sub search { |
822 |
my $self = shift; |
823 |
my ($query, $attr, $cont, $raw); |
824 |
if (ref $_[0]) { |
825 |
$query = shift; |
826 |
|
827 |
$attr = $query->{attr}; |
828 |
$cont = $query->{cont}; |
829 |
$raw = $query->{raw}; |
830 |
} else { |
831 |
require Carp; |
832 |
Carp::cluck("Using three argument search interface is deprecated, use hashref interface instead"); |
833 |
$attr = shift; |
834 |
$cont = shift; |
835 |
$raw = shift; |
836 |
$query = { |
837 |
attr => $attr, |
838 |
cont => $cont, |
839 |
raw => $raw, |
840 |
}; |
841 |
} |
842 |
|
843 |
my %result; |
844 |
|
845 |
defined $self->{db} or $self->open; # require layout |
846 |
|
847 |
if ($raw) { |
848 |
for (@{$self->{inverted}->{$attr}}) { |
849 |
my $name = $_->name; |
850 |
if (exists $raw->{$name} and @{$raw->{$name}}) { |
851 |
my $scale = 1/scalar(@{$raw->{$name}}); |
852 |
my %r = $_->search_raw($query, @{$raw->{$name}}); |
853 |
my ($key, $val); |
854 |
while (($key, $val) = each %r) { |
855 |
if (exists $result{$key}) { |
856 |
$result{$key} += $val*$scale; |
857 |
} else { |
858 |
$result{$key} = $val*$scale; |
859 |
} |
860 |
} |
861 |
} |
862 |
} |
863 |
} |
864 |
if (defined $cont and $cont ne '') { |
865 |
for (@{$self->{inverted}->{$attr}}) { |
866 |
my %r = $_->search($query, $cont); |
867 |
my ($key, $val); |
868 |
while (($key, $val) = each %r) { |
869 |
if (exists $result{$key}) { |
870 |
$result{$key} += $val; |
871 |
} else { |
872 |
$result{$key} = $val; |
873 |
} |
874 |
} |
875 |
} |
876 |
} |
877 |
# sanity check for deleted documents. |
878 |
# this should not be necessary !@#$ |
879 |
for (keys %result) { |
880 |
delete $result{$_} if $self->{deleted}->{$_} |
881 |
} |
882 |
%result; |
883 |
} |
884 |
|
885 |
sub hilight_positions { |
886 |
my ($self, $attr, $text, $query, $raw) = @_; |
887 |
my %pos; |
888 |
|
889 |
if (defined $raw) { |
890 |
for (@{$self->{inverted}->{$attr}}) { # objects of type |
891 |
# WAIT::InvertedIndex for |
892 |
# this index field $attr |
893 |
my $name = $_->name; |
894 |
if (exists $raw->{$name}) { |
895 |
my %qt; |
896 |
grep $qt{$_}++, @{$raw->{$name}}; |
897 |
for ($_->parse_pos($text)) { |
898 |
if (exists $qt{$_->[0]}) { |
899 |
$pos{$_->[1]} = max($pos{$_->[1]}, length($_->[0])); |
900 |
} |
901 |
} |
902 |
} |
903 |
} |
904 |
} |
905 |
if (defined $query) { |
906 |
for (@{$self->{inverted}->{$attr}}) { |
907 |
my %qt; |
908 |
|
909 |
grep $qt{$_}++, $_->parse($query); |
910 |
for ($_->parse_pos($text)) { |
911 |
if (exists $qt{$_->[0]}) { |
912 |
if (exists $pos{$_->[1]}) { # perl -w ;-) |
913 |
$pos{$_->[1]} = max($pos{$_->[1]}, length($_->[0])); |
914 |
} else { |
915 |
$pos{$_->[1]} = length($_->[0]); |
916 |
} |
917 |
} |
918 |
} |
919 |
} |
920 |
} |
921 |
|
922 |
\%pos; |
923 |
} |
924 |
|
925 |
sub hilight { |
926 |
my ($tb, $buf, $qplain, $qraw) = @_; |
927 |
my $layout = $tb->layout(); |
928 |
|
929 |
my @result; |
930 |
|
931 |
$qplain ||= {}; |
932 |
$qraw ||= {}; |
933 |
my @ttxt = $layout->tag($buf); |
934 |
while (@ttxt) { |
935 |
no strict 'refs'; |
936 |
my %tag = %{shift @ttxt}; |
937 |
my $txt = shift @ttxt; |
938 |
my $fld; |
939 |
|
940 |
my %hl; |
941 |
for $fld (grep defined $tag{$_}, keys %$qplain, keys %$qraw) { |
942 |
my $hp = $tb->hilight_positions($fld, $txt, |
943 |
$qplain->{$fld}, $qraw->{$fld}); |
944 |
for (keys %$hp) { |
945 |
if (exists $hl{$_}) { # -w ;-( |
946 |
$hl{$_} = max($hl{$_}, $hp->{$_}); |
947 |
} else { |
948 |
$hl{$_} = $hp->{$_}; |
949 |
} |
950 |
} |
951 |
} |
952 |
my $pos; |
953 |
my $qt = {_qt => 1, %tag}; |
954 |
my $pl = \%tag; |
955 |
my $last = length($txt); |
956 |
my @tmp; |
957 |
for $pos (sort {$b <=> $a} keys %hl) { |
958 |
unshift @tmp, $pl, substr($txt,$pos+$hl{$pos},$last-$pos-$hl{$pos}); |
959 |
unshift @tmp, $qt, substr($txt,$pos,$hl{$pos}); |
960 |
$last = $pos; |
961 |
} |
962 |
push @result, $pl, substr($txt,0,$last); |
963 |
push @result, @tmp; |
964 |
} |
965 |
@result; # no speed necessary |
966 |
} |
967 |
|
968 |
1; |