# NAME PICA::Data - PICA record processing [![Unix build Status](https://travis-ci.com/gbv/PICA-Data.png)](https://travis-ci.com/gbv/PICA-Data) [![Windows build status](https://ci.appveyor.com/api/projects/status/5qjak74x7mjy7ne6?svg=true)](https://ci.appveyor.com/project/nichtich/pica-data) [![Coverage Status](https://coveralls.io/repos/gbv/PICA-Data/badge.svg)](https://coveralls.io/r/gbv/PICA-Data) [![Kwalitee Score](http://cpants.cpanauthors.org/dist/PICA-Data.png)](http://cpants.cpanauthors.org/dist/PICA-Data) # 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 ); use PICA::Schema; $schema = PICA::Schema->new(); # parse records while ( my $record = $parser->next ) { # function accessors my $ppn = pica_value($record, '003@0'); my $ppn = pica_match($record, '045Ue', split => 1, nested_array => 1); my $holdings = pica_holdings($record); my $items = pica_items($record); ... # object accessors my $ppn = $record->id; my $ppn = $record->value('003@0'); my $ddc = $record->match('045Ue', split => 1, nested_array => 1); my $holdings = $record->holdings; my $items = $record->items; ... # write record $writer->write($record); # write methods $record->write($writer); $record->write( xml => @options ); $record->write; # default "plain" writer # stringify record my $plain = $record->string; my $xml = $record->string('xml'); # validate record my $errors = $schema->check($record); } # parse single record from string my $record = pica_parser('plain', \"...")->next; # guess parser from input string my $parser = pica_guess($string)->new(\$string); # DESCRIPTION PICA::Data provides methods, classes, functions, and [a command line application](https://metacpan.org/pod/picadata) to process [PICA+ records](http://format.gbv.de/pica). 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 keys, `_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 (having tag `003@` and no occurrence): { _id => '12345X', record => [ [ '003@', undef, '0' => '12345X' ] ] } or in short form: [ [ '003@', undef, '0' => '12345X' ] ] PICA path expressions (see [PICA::Path](https://metacpan.org/pod/PICA::Path)) can be used to facilitate processing PICA+ records and [PICA::Schema](https://metacpan.org/pod/PICA::Schema) can be used to validate PICA+ records with [Avram Schemas](https://format.gbv.de/schema/avram/specification). # 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](https://metacpan.org/pod/PICA::Parser::Base)). Case of the type is ignored and additional parameters are passed to the parser's constructor: - [PICA::Parser::Binary](https://metacpan.org/pod/PICA::Parser::Binary) for type `binary` (binary PICA+) - [PICA::Parser::Plain](https://metacpan.org/pod/PICA::Parser::Plain) for type `plain` or `picaplain` (human-readable PICA+) - [PICA::Parser::Plus](https://metacpan.org/pod/PICA::Parser::Plus) for type `plus` or `picaplus` (normalized PICA+) - [PICA::Parser::JSON](https://metacpan.org/pod/PICA::Parser::JSON) for type `json` (PICA JSON) - [PICA::Parser::XML](https://metacpan.org/pod/PICA::Parser::XML) for type `xml` or `picaxml` (PICA-XML) - [PICA::Parser::PPXML](https://metacpan.org/pod/PICA::Parser::PPXML) for type `ppxml` (PicaPlus-XML) ## pica\_guess( $data ) Guess PICA serialization format from input data. Returns name of the corresponding parser class or `undef`. ## pica\_xml\_struct( $xml, %options ) Convert PICA-XML, expressed in [XML::Struct](https://metacpan.org/pod/XML::Struct) structure into a PICA::Data object. ## pica\_writer( $type \[, @options\] ) Create a PICA writer object (see [PICA::Writer::Base](https://metacpan.org/pod/PICA::Writer::Base)) in the same way as `pica_parser` with one of - [PICA::Writer::Binary](https://metacpan.org/pod/PICA::Writer::Binary) for type `binary` (binary PICA) - [PICA::Writer::Generic](https://metacpan.org/pod/PICA::Writer::Generic) for type `generic` (PICA with self defined data separators) - [PICA::Writer::Plain](https://metacpan.org/pod/PICA::Writer::Plain) for type `plain` or `picaplain` (human-readable PICA+) - [PICA::Writer::Plus](https://metacpan.org/pod/PICA::Writer::Plus) for type `plus` or `picaplus` (normalized PICA+) - [PICA::Writer::JSON](https://metacpan.org/pod/PICA::Writer::JSON) for type `json` (PICA JSON) - [PICA::Writer::XML](https://metacpan.org/pod/PICA::Writer::XML) for type `xml` or `picaxml` (PICA-XML) - [PICA::Writer::PPXML](https://metacpan.org/pod/PICA::Writer::PPXML) for type `ppxml` (PicaPlus-XML) ## pica\_string( $record \[, $type \[, @options\] \] ) Stringify a record with given writer (`plain` as default) and options. ## pica\_path( $path ) Equivalent to [PICA::Path](https://metacpan.org/pod/PICA::Path)->new($path). ## pica\_match( $record, $path, %options ) Equivalent to [PICA::Path](https://metacpan.org/pod/PICA::Path)->match\_record($path, %options). Extract the subfield values from a PICA record based on a PICA path expression and options (see [PICA::Path](https://metacpan.org/pod/PICA::Path)). Also available as accessor `match($path, %options)`. ## 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); ## pica\_fields( $record\[, $path...\] ) Returns a PICA record (or empty array reference) limited to fields specified in one ore more PICA path expression. The following are virtually equivalent: pica_fields($record, $path); $path->record_fields($record); $record->fields($path); ## pica\_title( $record ) Returns the record limited to level 0 fields ("title record") in sorted order. ## pica\_holdings( $record ) Returns a list (as array reference) of local holding records, sorted by ILN. Level2 fields are included in sorted order. The ILN (if given) is available as `_id`. Also available as accessor `holdings`. ## pica\_items( $record ) Returns a list (as array reference) of item records. The EPN (if given) is available as `_id` Also available as accessor `items`. ## pica\_split( $record) Returns the record splitted into multiple records for each level. ## pica\_sort( $record ) Returns a copy of the record with sorted fields (first level 1 fields, then level 2 fields not belonging to a level 1, then level 1, each followed by level 2 sorted by EPN). Also available as accessor `sort`. ## pica\_annotation( $field \[, $annotation \] ) Get or set a PICA field annotation. Use `undef` to remove annotation. ## pica\_diff( $before, $after ) Return the difference between two records as annotated record. Also available as method `diff`. See [PICA::Patch](https://metacpan.org/pod/PICA::Patch) for details. ## pica\_patch( $record, $diff ) Return a new record by application of a difference given as annotated PICA. Also available as method `patch`. See [PICA::Patch](https://metacpan.org/pod/PICA::Patch) for details. # ACCESSORS All accessors of `PICA::Data` are also available as ["FUNCTIONS"](#functions), prefixed with `pica_` (see ["SYNOPSIS"](#synopsis)). ## match( $path, %options ) Extract a list of subfield values from a PICA record based on a [PICA::Path](https://metacpan.org/pod/PICA::Path) expression and options. ## values( $path ) Extract a list of subfield values from a PICA record based on a [PICA::Path](https://metacpan.org/pod/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](https://metacpan.org/pod/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`). ## id Returns the record id, if given. ## empty Tell whether the record is empty (no fields). # METHODS ## write( \[ $type \[, @options\] \] | $writer ) Write PICA record with given [PICA::Writer::...](https://metacpan.org/pod/PICA::Writer::Base) or [PICA::Writer::Plain](https://metacpan.org/pod/PICA::Writer::Plain) by default. This are equivalent: pica_writer( xml => $file )->write( $record ); $record->write( xml => $file ); ## string( \[ $type \] ) Serialize PICA record in a given format (`plain` by default). This method can also be used as function `pica_string`. ## diff( $record ) Calculate the difference of the record to another record. ## patch( $diff ) Calculate a new record by application of an annotated PICA record. Annotations `+` and `-` denote fields to be added or removed. Fields with blank annotations are check to exist in the original record. The records should not contain multiple records of level 1 and/or level 2. # CONTRIBUTORS Johann Rolschewski, `` Jakob Voß `` Carsten Klee `` # COPYRIGHT AND LICENSE Copyright 2014- Johann Rolschewski and Jakob Voss This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. # SEE ALSO - [picadata](https://metacpan.org/pod/picadata) command line script to parse, serialize, count, and validate PICA+ data. - Use [Catmandu::PICA](https://metacpan.org/pod/Catmandu::PICA) for more elaborated processing of PICA records with the [Catmandu](https://metacpan.org/pod/Catmandu) toolkit. - [PICA::Record](https://metacpan.org/pod/PICA::Record) implemented an alternative framework for processing PICA+ records (**deprecated!**).