DSpace exports

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Main Page > Development > Development documentation > DSpace exports

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

Collection export

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

Notes

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


  • The text file bitstreams in the other 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


  • 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>?

Collection-level mets.xml file

The mets.xml file for the collection is structured as follows:

  • <mets ID="DSpace_COLLECTION_123456789-6" OBJID="hdl:123456789/6" TYPE="DSpace COLLECTION" PROFILE="http://www.dspace.org/schema/aip/mets_aip_1_0.xsd" xsi:schemaLocation="http://www.loc.gov/METS/ http://www.loc.gov/standards/mets/mets.xsd">
  • <metsHdr>
  • <dmdSec> (contains MODS metadata for collection-level description)
  • <dmdSec> (contains DSpace Intermediate Metadata (DIM) for collection-level description; all mapped to dc; some overlap with MODS metadata)
  • <amdSec> (contains information on DSpace users and groups associated with the collection)
  • <fileSec> (references the collection's logo, if there is one)
  • <structMap> (links the collection to its logo, if there is one, plus its two child items)
  • <structMap> (links the collection to the DSpace Community)

Item-level mets.xml file

  • <metsHdr>
  • <dmdSec_1> (contains MODS metadata for item)
  • <dmdSec_2> (contains DIM metadata for item; all mapped to dc; some overlap with MODS metadata)
  • <amdSec> (contains rights metadata)
  • <amdSec> (contains rights metadata)
  • <amdSec> (contains PREMIS object metadata; rights metadata; DIM metadata for the item)
  • <amdSec> (contains rights metadata)
  • <amdSec> (contains PREMIS object metadata; rights metadata; DIM metadata for the licence)
  • <fileSec> (lists the item and its license)
  • <structMap> (links the bitstream to the logical object)
  • <structMap> (links the item to the collection)

Parsing a DSpace collection export in Archivematica

Requirements:

  • Map the elements of the DSpace AIPs to the Archivematica AIP
  • Structure the Archivematica mets.xml file to point to the DSpace mets.xml files
  • Index the metadata in all the xml files

Map the elements of the DSpace AIPs to the Archivematica AIP

  • The digital objects get placed in the objects directory
  • The license files get placed in the metadata/submissiondocumentation directory; the text is parsed to the <rights> container in the PREMIS metadata. See PREMIS metadata: rights#License-based
  • The mets.xml files get placed in the metadata/submissionDocumentation directory...hmm, why not put them in the metadata directory?

Link the object to its METS file

Each object in a DSpace AIP comes with its own METS file containing descriptive and rights metadata as well as some PREMIS object metadata.

Archivematica mets.xml file:

METS file section Description/notes
<dmdSec> DC metadata added during transfer/ingest; SIP-level only
<amdSec> PREMIS metadata
<fileSec> Lists all the files in the objects directory of the AIP
<structMap> Groups the contents in the objects directory of the AIP to reflect the folder structure of the AIP


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?