GRS1(3pm)						User Contributed Perl Documentation						 GRS1(3pm)

NAME

       Net::Z3950::Record::GRS1 - Perl package used to encode GRS-1 records.

SYNOPSIS

	 use Net::Z3950::GRS1;

	 my $a_grs1_record = new Net::Z3950::Record::GRS1;
	 my $another_grs1_record = new Net::Z3950::Record::GRS1;

	 $a_grs1_record->AddElement($type, $value, $content);
	 $a_grs1_record->Render();

DESCRIPTION

       This Perl module helps you to create and manipulate GRS-1 records (generic record syntax).  So far, you have only access to three methods:

   new
       Creates a new GRS-1 object,

	 my $grs1 = new Net::Z3950::GRS1;

   AddElement
       Lets you add entries to a GRS-1 object. The method should be called this way,

	 $grs1->AddElement($type, $value, $which, $content);

       where $type should be an integer, and $value is free text. The $which argument should contain one of the constants listed in Appendix A.
       Finally, $content contains the "thing" that should be stored in this entry. The structure of $content should match the chosen element data
       type. For

	 $which == Net::Z3950::GRS1::ElementData::String;

       $content should be some kind of scalar. If on the other hand,

	 $which == Net::Z3950::GRS1::ElementData::Subtree;

       $content should be a GRS1 object.

   Render
       This method digs through the GRS-1 data structure and renders the record. You call it this way,

	 $grs1->Render();

       If you want to access the rendered record through a variable, you can do it like this,

	 my $record_as_string;
	 $grs1->Render(POOL => $record_as_string);

       If you want it stored in a file, Render should be called this way,

	 $grs1->Render(FILE => 'record.grs1');

       When no file name is specified, you can choose to stream the rendered record, for instance,

	 $grs1->Render(HANDLE => *STDOUT);	       ## or
	 $grs1->Render(HANDLE => *STDERR);	       ## or
	 $grs1->Render(HANDLE => *MY_HANDLE);

   Hash2grs
       This method converts a hash into a GRS-1 object. Scalar entries within the hash are converted into GRS-1 string elements. A hash entry can
       itself be a reference to another hash. In this case, the new referenced hash will be converted into a GRS-1 subtree. The method is called
       this way,

	 $grs1->Hash2grs($href, $mapping);

       where $href is the hash to be converted and $mapping is referenced hash specifying the mapping between keys in $href and (type, value)
       pairs in the $grs1 object. The $mapping hash could for instance look like this,

	 my $mapping = {
			       title   =>      [2, 1],
			       author  =>      [1, 1],
			       issn    =>      [3, 1]
		       };

       If the $grs1 object contains data prior to the invocation of Hash2grs, the new data represented by the hash is simply added.

APPENDIX A

       These element data types are specified in the Z39.50 protocol:

	 Net::Z3950::GRS1::ElementData::Octets
	 Net::Z3950::GRS1::ElementData::Numeric
	 Net::Z3950::GRS1::ElementData::Date
	 Net::Z3950::GRS1::ElementData::Ext
	 Net::Z3950::GRS1::ElementData::String		       <---
	 Net::Z3950::GRS1::ElementData::TrueOrFalse
	 Net::Z3950::GRS1::ElementData::OID
	 Net::Z3950::GRS1::ElementData::IntUnit
	 Net::Z3950::GRS1::ElementData::ElementNotThere
	 Net::Z3950::GRS1::ElementData::ElementEmpty
	 Net::Z3950::GRS1::ElementData::NoDataRequested
	 Net::Z3950::GRS1::ElementData::Diagnostic
	 Net::Z3950::GRS1::ElementData::Subtree 	       <---

       Only the '<---' marked types are so far supported in this package.

AUTHOR

       Anders Sonderberg Mortensen <sondberg@indexdata.dk> Index Data ApS, Copenhagen, Denmark.  2001/03/09

SEE ALSO

       Specification of the GRS-1 standard, for instance in the Z39.50 protocol specification.

perl v5.14.2							    2011-08-09								 GRS1(3pm)