DSpace exports

From Archivematica
Revision as of 18:13, 19 September 2011 by Evelyn (talk | contribs)
Jump to navigation Jump to search

Main Page > Development > Development documentation > DSpace exports

This page analyzes the structure of a DSpace collection export from an uncustomized (i.e. out of the box) DSpace installation.

Used the following command (from DSpace user documentation) to export a two-item collection with the handle 123456789-6:

./dspace packager -d -a -t AIP -e <user name> -i 123456789-6 calamy.zip

This results in the export of three zipped packages: one for the collection and one for each of the items:

  • calamy.zip
  • ITEM@123456789-7.zip
  • ITEM@123456789-8.zip

The extracted contents of each zipped file are shown in this screenshot:

Export.png

Item-level METS files

Link to object

  • The mets.xml file is linked to the object by the handle of the original zipped file:
MetsID.png

Licenses

The text file bitstreams in the two item-level directories are licenses. Note that they are not identified by filename as license files - Archivematica will need to recognize license files from each object's METS file (i.e. from fileSec). Here is an example of the fileSec showing the object to be preserved (bitstream_12.png) and its license file (bitstream_13):

FileSec.png

Archivematica should move the license file to the metadata/submissionDocumentation directory; the text can be parsed to the <rights> container in the PREMIS metadata. See PREMIS metadata: rights#License-based

RightsMD

Each object also has an amdSec containing rightsMD data (populated automatically according to DSpace configuration settings):

Rights.png

Should Archivematica parse this rightsMD metadata to the PREMIS file?

Descriptive metadata

  • Each object has two dmdSecs: MODS and DSpace Intermediate Metadata (DIM).
    • The DIM metadata is not intended for use outside of DSpace: according to the DSpace website, "[DIM] is used by XsltCrosswalk. It is called the Intermediate format because it is intended solely as an intermediate stage in XML-translation-based crosswalks. To reiterate, This is an INTERMEDIATE format, it is NOT for exporting or harvesting metadata!"
  • What should we do with the MODS metadata?
    • Leave it in the DSpace METS file and just link the object to its METS file?
    • Add an <mdRef> to the Archivematica METS file to link each object to its MODS metadata?
    • Add the MODS metadata to the Archivematica METS file as <mdWrap>?

Checksums

Each object and license has an MD5 checksum recorded in the fileSec.

FileSec.png

Archivematica should verify these checksums after transfer.

Collection-level mets files

The collection-level mets file contains MODS and DIM metadata for the collection; the MODS metadata should be linked or added to the Archivematica mets file.

Parsing a DSpace collection export in Archivematica

Requirements:

  • Map the elements of the DSpace AIPs to the Archivematica AIP
    • Keep the object in /objects
    • Move the license file to /metadata/submissionDocumentation
    • Move the mets file to /metadata
  • Structure the Archivematica mets.xml file to point to the DSpace mets.xml files
    • Question: how do we link the object to the DSpace METS file? Give the METS file a UUID and make the link in the PREMIS relationships container?
  • Index the metadata in all the xml files