NAME

PICA::Data - PICA record processing

SYNOPSIS

  use PICA::Data ':all';
  $parser = pica_parser( xml => 'picadata.xml' );
  $writer = pica_writer( plain => \*STDOUT );
 
  use PICA::Parser::XML;
  use PICA::Writer::Plain;
  $parser = PICA::Parser::XML->new( @options );
  $writer = PICA::Writer::Plain->new( @options );

  # parse records
  while ( my $record = $parser->next ) {
      
      # function accessors
      my $ppn      = pica_value($record, '003@0');
      my $holdings = pica_holdings($record);
      my $items    = pica_items($record);
      ...

      # object accessors (if parser option 'bless' enabled)
      my $ppn      = $record->{_id};
      my $ppn      = $record->value('003@0');
      my $holdings = $record->holdings;
      my $items    = $record->items;
      ...

      # write record
      $writer->write($record);
      
      # write record via method (if blessed)
      $record->write($writer);
      $record->write( xml => @options );
      $record->write; # default "plain" writer

      # stringify record
      my $plain = $record->string;
      my $xml = $record->string('xml');
  }

  # parse single record from string
  my $record = pica_parser('plain', \"...")->next;

DESCRIPTION

PICA::Data provides methods, classes, and functions to process PICA+ records in Perl.

PICA+ is the internal data format of the Local Library System (LBS) and the Central Library System (CBS) of OCLC, formerly PICA. Similar library formats are the MAchine Readable Cataloging format (MARC) and the Maschinelles Austauschformat fuer Bibliotheken (MAB). In addition to PICA+ in CBS there is the cataloging format Pica3 which can losslessly be convert to PICA+ and vice versa.

Records in PICA::Data are encoded either as array of arrays, the inner arrays representing PICA fields, or as an object with two fields, _id and record, the latter holding the record as array of arrays, and the former holding the record identifier, stored in field 003@, subfield 0. For instance a minimal record with just one field 003@:

{
  _id    => '12345X',
  record => [
    [ '003@', undef, '0' => '12345X' ]
  ]
}

or in short form:

[ [ '003@', undef, '0' => '12345X' ] ]

PICA path expressions (see PICA::Path) can be used to facilitate processing PICA+ records.

FUNCTIONS

The following functions can be exported on request (use export tag :all to get all of them):

pica_parser( $type [, @options] )

Create a PICA parsers object (see PICA::Parser::Base). Case of the type is ignored and additional parameters are passed to the parser's constructor:

PICA::Parser::Plus for type plus or picaplus (normalized PICA+)
PICA::Parser::Plain for type plain or picaplain (human-readable PICA+)
PICA::Parser::XML for type xml or picaxml (PICA-XML)
PICA::Parser::PPXML for type ppxml (PicaPlus-XML)

pica_xml_struct( $xml, %options )

Convert PICA-XML, expressed in XML::Struct structure into an (optionally blessed) PICA record structure.

pica_writer( $type [, @options] )

Create a PICA writer object (see PICA::Writer::Base) in the same way as pica_parser with one of

PICA::Writer::XML for type xml or picaxml (PICA-XML)
PICA::Writer::Plus for type plus or picaplus (normalized PICA+)
PICA::Writer::Plain for type plain or picaplain (human-readable PICA+)

pica_path( $path )

Equivalent to PICA::Path->new($path).

pica_value( $record, $path )

Extract the first subfield values from a PICA record based on a PICA path expression. Also available as accessor value($path).

pica_values( $record, $path )

Extract a list of subfield values from a PICA record based on a PICA path expression. The following are virtually equivalent:

pica_values($record, $path);
$path->record_subfields($record);
$record->values($path); # if $record is blessed

pica_fields( $record, $path )

Returns a PICA record (or empty array reference) limited to fields specified in a PICA path expression. The following are virtually equivalent:

pica_fields($record, $path);
$path->record_fields($record);
$record->fields($path); # if $record is blessed

pica_holdings( $record )

Returns a list (as array reference) of local holding records. Also available as accessor holdings.

pica_items( $record )

Returns a list (as array reference) of item records. Also available as accessor items.

ACCESSORS

All accessors of PICA::Data are also available as "FUNCTIONS", prefixed with pica_ (see "SYNOPSIS").

values( $path )

Extract a list of subfield values from a PICA record based on a PICA::Path expression.

value( $path )

Same as values but only returns the first value.

fields( $path )

Returns a PICA record limited to fields specified in a PICA::path expression. Always returns an array reference.

holdings

Returns a list (as array reference) of local holding records (level 1 and 2), where the _id of each record contains the ILN (subfield 101@a).

items

Returns a list (as array reference) of item records (level 1), where the _id of each record contains the EPN (subfield 203@/**0).

METHODS

write( [ $type [, @options] ] | $writer )

Write PICA record with given PICA::Writer::Base or PICA::Writer::Plain by default. This method is a shortcut for blessed record objects:

pica_writer( xml => $file )->write( $record );
$record->write( xml => $file ); # equivalent if $record is blessed

CONTRIBUTORS

Johann Rolschewski, <rolschewski@gmail.com>

Jakob Voss <voss@gbv.de>

COPYRIGHT AND LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

cKlee/PICA-Data