Metacat

#!/usr/bin/perl

# This script is INCOMPLETE -- see TODO markers throughout

# This script loops through a list of metadata documents and associated data

# files, and for each one uploads the data file to metacat, puts the accession 

# number in the metadata, then inserts the metadata to metacat.

# Matt Jones February 14, 2008

use Metacat;

use XML::DOM;

use strict;

############################################################################

#

# MAIN program block

#

############################################################################

# check that the correct number or parameters are passed from the commandline

if (($#ARGV +1) != 1) {die "Usage: %./insert_fgdc.pl <metacat_url> \n\n";}

# Get the URL to the metacat server from the command line options

my ($url) = @ARGV; 

my $dn = 'uid=jones,o=NCEAS,dc=ecoinformatics,dc=org';

my $password = 'foobar';

# Open a metacat connection and login

my $metacat = openMetacatConnection($url);

loginToMetacat($metacat, $dn, $password);

# Read in the list of FGDC documents

my $dataDir = "/tmp/data";

# datalist key = data filename, value = metadata filename

my $datalist = getDataList($dataDir); 

my $datafilename;

# Loop through the list of datafiles

foreach $datafilename (keys %$datalist) {

    print("Processing...  $datafilename $$datalist{$datafilename}\n");

    # Upload the data file into Metacat, catching accession # errors

    my $dataId = uploadData($metacat, $datafilename);

    # Reference the accession # URL for the data file in the FGDC metadata

    my $metadata = createDataReference($dataId, $$datalist{$datafilename});

    # Insert the metadata file into Metacat, catching accession # errors

    my $metadataId = insertMetadata($metacat, $metadata );

    # Set access control rules for the metadata and data files

    setAccess($dataId);

    setAccess($metadataId);

}

exit(0);

############################################################################

#

# SUBROUTINES

#

############################################################################

#

# Create a connection to the metacat server

#

sub openMetacatConnection {

    my $url = shift;

    my $metacat = Metacat->new();

    if ($metacat) {

        $metacat->set_options( metacatUrl => $url );

    } else {

        die("Could not open connection to Metacat url: $url\n");

    }

    return $metacat;

}

#

# Login to the metacat server

#

sub loginToMetacat {

    my $metacat = shift;

    my $dn = shift;

    my $password = shift;

    my $response1 = $metacat->login($dn, $password);

    if (! $response1) {

        print $metacat->getMessage();

        print "Failed during login: metacat.\n";

    } else {

        print "Connected to metacat\n";

    }

}

#

# TODO

# Get a hashed list of datafile names and their associated metadata file names

#

sub getDataList {

    my $dataDir = shift;

    my %dataList = ("datafile_a"=>"metadatafile_ma", 

                    "datafile_b"=>"metadatafile_mb");

    return \%dataList;

}

#

# TODO

# Upload a data file to metacat, returning the identifier used

#

sub uploadData {

    my $metacat = shift;

    my $datafilename = shift;

    # TODO: Create a unique ID

    my $identifier;

    # TODO: Read in the data file from disk

    # my $data;

    # TODO: Do the metacat insertion as a MIME insertion

    #my $response = $metacat->upload($identifier, $data);

    # TODO: Check the insertion succeeded, if not possibly try again with new id

	my $message =  $metacat->getMessage();

    return $identifier;

    return $identifier;

}

#

# TODO

# Insert a reference to a data file into the FGDC metadata document

#

sub createDataReference {

    my $metacat = shift;

    my $dataId = shift;

    my $metadatafilename = shift;

    my $metadata;

    return $metadata;

}

#

# TODO

# Insert the metadata document into the Metacat database

#

sub insertMetadata {

    my $metacat = shift;

    my $metadatafilename = shift;

    # TODO: Create a unique ID

    my $identifier;

    # TODO: Read in the metadata file from disk

    # my $metadata;

    # Do the metacat insertion

    # my $response = $metacat->insert($identifier, $metadata);

    # TODO: Check the insertion succeeded, if not possibly try again with new id

	my $message =  $metacat->getMessage();

    return $identifier;

}

#

# TODO

# Set access control permissions on the file identified

#

sub setAccess {

    my $metacat = shift;

    my $identifier;

}