NAME

SeeAlso::Source::BeaconAggregator::Publisher - additional methods for SeeAlso::Source::BeaconAggregator

SYNOPSIS

  $source = SeeAlso::Source::BeaconAggregator::Publisher->new(...);

DESCRIPTION

This package provides the functionallity to export a BEACON file from the data connected with an SeeAlso::Source::BeaconAggregator instance and also the additional formats "redirect" and "sources" which universally can be used as callbacks for SeeAlso::Server (replacing the default "seealso" method yielding JSON data).

new ( ... )

Creates an SeeAlso::Source::BeaconAggregator object with additional methods from this package enabled

activate ()

Makes SeeAlso::Source::BeaconAggregator objects member of this class, globally enabling the additional methods

Usage:

  $db = SeeAlso::Source::BeaconAggregator::Maintenance->new(...);
  ...
  do stuff
  ...
  require SeeAlso::Source::BeaconAggregator::Publisher
          or die "could not require Publisher extension";
  SeeAlso::Source::BeaconAggregator::Publisher->activate();   # "recast" all objects
  ...
  do more stuff

beacon ( [dumpmeta arguments] )

produces a BEACON file (however, $cgibase is mandatory)

dumpmeta ( [$cgibase, [$uAformatname, [$headersonly]]] [, $preset])

produces only the meta fields of a BEACON file

Meta fields are generated from the $preset Hashref, falling back to values stored in the database, falling back to reasonable default values.

Arguments:

$cgibase

URL of the SeeAlso service the BEACON file is provided for

$uAformatname

unAPI format name to be used as target (Default: "sources")

$headersonly

currently unused

$preset

Hashref of Beacon header fields overriding the contents of the database

Regular Usage:

  $db = SeeAlso::Source::BeaconAggregator::Publisher->new(...);
  binmode(STDOUT, ":utf8");
  my $cgibase = "http://address/of/service";
  my ( $error, $headerref) = $db->beacon($cgibase, @ARGV, {'FORMAT' => 'PND-BEACON'});

CGI Usage:

  $format = $CGI->param('format') || "";
  if ( $format eq "beacon" ) {  # bypass SeeAlso::Server->query() b/c performance / interim storage
                                  insert access restrictions here...
      do_beacon($source, $CGI);
    }
  ...

 sub do_beacon {
   my ($self, $cgi) = @_;           # Of type SeeAlso::Source::BeaconAggregator
   unless ( $self->can("beacon") ) {
       croak "On the fly generation of beacon Files not supported by this service";}
   my $cgibase = $cgi->url(-path_info=>1);

   print $cgi->header( -status => 200,
                      -expires => '+1d',
                         -type => 'text/plain',
                      -charset => 'utf-8',
                      );
   return $self->beacon($cgibase, "sources", {});     # prints directly to stdout..., returns $error, $headerref
 }

redirect ( $server, $format, $extra, $query )

Produces an HTTP redirect page, HTML content contains very terse details in case of multiple results.

This subroutine may be used as callback method in SeeAlso::Server

Usage is a bit cludgy due to author's lack of understanding of SeeAlso::Server

  $source = SeeAlso::Sources::BeaconAggregator::Publisher->new(...);
  $CGI = CGI->new();

  $formats = {
    ...
    redirect => {
           type => "text/html", 
           docs => "http://www.endofthe.net/",
#        method => \&SeeAlso::Source::BeaconAggregator::Publisher::redirect,
  #redirect_300 => 'sources',
                }
  };

  $server   = SeeAlso::Server->new (
          'cgi' => $CGI,
      'formats' => $formats,
       ...
  );

  # Closure as fix: Server.pm does not expose self, $source and the CGI object to the format methods
  my $oref = \&SeeAlso::Source::BeaconAggregator::Publisher::redirect;
  $server->{'formats'}->{'redirect'}->{method}
    = sub {return &$oref($source, $server, $method, $formats->{$method}, @_)};

  my $result = $server->query($source);

Arguments:

$server

SeeAlso::Server object. Must contain a CGI object

$format

Name of a format registered with the $server object ()

$extra

Hashref with the following configuration directives

  redirect_300 => CGI 'format' parameter to be used in HTML content (eg. format=sources)

  force_single => Only regard the first hit (thus always redirect)

$query

Identifier to be queried

sources ( $server, $format, $extra, $query )

Produces an HTML page with details to the queried identifier (description of sources)

This subroutine may be used as callback method in SeeAlso::Server (cf. description of redirect above

$server

SeeAlso::Server object

$format

Format selected for $server

$extra

Hashref with the following configuration directives

  css => URL of css file to be referenced

$query

Identifier to be queried

get_meta ()

Returns a pair of hash references:

1. OSD fields

2. Beacon header fields

AUTHOR

    Thomas Berger
    CPAN ID: THB
    gymel.com
    THB@cpan.org

COPYRIGHT

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

The full text of the license can be found in the LICENSE file included with this module.

cpanm SeeAlso::Source::BeaconAggregator

perl -MCPAN -e shell
install SeeAlso::Source::BeaconAggregator