Information Technology Reference
In-Depth Information
CASPAR XFDU packages are connected to the RIN in the CASPAR Registry
using the attributes of the XFDU metadataReference element, as demonstrated
in the example below. Using OAIS terminology, the containing metadataObject
is classified and categorized as Data Entity Description (DED) RepInfo; we use
the vocabularyName attribute to also identify the object as 'SEMANTIC'. The
RepInfo object in the CASPAR/DCC RRORI is referenced by a URI through the
href attribute, the otherLocatorType attribute indicating that the URI is a CPID. The
id attribute also contains the CPID.
<metadataObject category
=
"
REP
" classification
=
"
DED
"
ID
=
"
REP_DESCRIPTION01">
<metadataReference
vocabularyName
=
"
SEMANTIC
" otherLocatorType
=
"
CPID
"
locatorType
=
"
OTHER
"
href
=
"http://registry.dcc.ac.uk/omar/registry/http?interface
=
QueryManager&
method
=
getRepositoryItem&param-id
=
urn:uuid:40e0c3de-
a405-4759-b116-
eda15d77df59"
textInfo
=
"Semantic Information about MST version 3 NetCDF
data files
"
ID
=
"cpid-40e0c3de-a405-4759-b116-eda15d77df59" />
</metadataObject>
Given the data to preserve and a CPID, the CASPAR packaging component can
pull extra information from the RRORI upon package construction - such as tex-
tual descriptions of the RepInfo, which can be inserted into the XFDU manifest.
This method provides an entry point into the RIN, a first level dependency. Using
the CASPAR Packaging sub-system it is possible to download all further necessary
RepInfo in the network for addition into an AIP.
Using the Packaging and Registry APIs for this purpose the Packaging
Visualization Tool provides the visual inspection and construction of RIR connected
XFDU AIPs. Having been developed over the packaging API, the tool is flexible
enough to allow alternative packaging formats to be used, for example a METS
toolkit could used in place of the XFDU toolkit allowing the visual construction and
visualization of METS based AIPs.
Figure
17.27
shows an example of using the tool to construct an MST package,
where the AIPs first level RepInfo dependencies are embedded within the package
itself with subsequent levels stored in the Registry.
