Editing SWORD 2.0 (section)

==== Basic framework ====
The very basic framework for an importer is just to register the importer with EPrints, and leave all functions to be handled by inheritence:

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package EPrints::Plugin::Import::RJ_Broker_2;

use strict;

use EPrints::Plugin::Import::Binary;
use EPrints::Plugin::Import::Archive;

our @ISA = qw/ EPrints::Plugin::Import::Archive /;

sub new 
{
  my ( $class, %params ) = @_;

  my $self = $class->SUPER::new(%params);

  # The name to display
  $self->{name} = "RJ_Broker package";

  # Who can see it, and whether we show it
  $self->{visible}   = "all";
  $self->{advertise} = 1;

  # What the importer produces
  $self->{produce} = [qw( list/eprint dataobj/eprint )];

  # What mime-types can trigger this importer
  $self->{accept} = [ "application/vnd.rjbroker",
    "sword:http://opendepot.org/broker/1.0" ];

  return $self;
} ## end sub new

1;
</pre>
This defines a few important things:
<pre>
  $self->{name} = "RJ_Broker package";
</pre>
is the name to display in public

<pre>
  # What the importer produces
  $self->{produce} = [qw( list/eprint dataobj/eprint )];
</pre>
defines what the importer actually returns (some handle specific files [.pdf, .doc, .mp3], others may import several records in one go [eg EndNote files])

<pre>
  # What mime-types can trigger this importer
  $self->{accept} = [ "application/vnd.rjbroker",
    "sword:http://opendepot.org/broker/1.0" ];
</pre>
Defines what content-types andh/or package-types trigger the use of this importer.
(two importers registering to handle the same content-type is A bad Thing<sup>[tm]</sup>

Whilst this is pretty, it's actually pretty useless as all it will do is replicate what <tt>Import::Archive</tt> does. To be useful, it needs to somehow read in some metadata and maybe attach some files.

The first important task will be to handle the file deposited. For this, you need to create a function called <code>input_fh</code>, and it will have a framework something like:

<pre>
sub input_fh 
{
  my ( $plugin, %opts ) = @_;

  my $fh      = $opts{fh};
  my $dataset = $opts{dataset};
  my $repo    = $plugin->{session};

  # get the type of file (should be zip) and the filename ($zipfile) for
  # the file just deposited.
  # (local method)
  my $zipfile = $plugin->upload_archive($fh);

  ## Do magic to get the XML file with the metadata
  my $epdata = $plugin->parse_epdcx_xml_data($xml_data);

  my $dataobj = $plugin->epdata_to_dataobj( $dataset, $epdata );
  if ( defined $dataobj ) {
    push @ids, $dataobj->get_id;
  }

  return EPrints::List->new(
    dataset => $dataset,
    session => $repo,
    ids     => \@ids
  );

}

sub upload_archive 
{
  my ( $self, $fh ) = @_;

  use bytes;

  binmode($fh);

  my $zipfile = File::Temp->new();
  binmode($zipfile);

  my $rc;
  my $lead;
  while ( $rc = sysread( $fh, my $buffer, 4096 ) ) {
    $lead = $buffer if !defined $lead;
    syswrite( $zipfile, $buffer );
  }
  EPrints->abort("Error reading from file handle: $!") if !defined $rc;

  return $zipfile;
} ## end sub upload_archive

sub parse_epdcx_xml_data
{
  my ( $plugin, $xml ) = @_;

  my $epdata         = {};
 
  ## parse the XML as needed...

  return $epdata;
} ## end sub parse_epdcx_xml_data

</pre>