Implementation using Fez

From TARDIS

These are brief notes for the time being.

Fez is a Fedora front-end developed at UQ as part of the Australian Partnership for Sustainable Repositories. It is deployed at the UQ library and is the institutional repository targeted by the UQ component of TARDIS.

[edit] Schema Mapping

Fez provides a means for mapping XML Schemas (XSDs) to input and display elements. It can handle different datatypes (text, numbers, dates, etc) and has some support for nested and repeating XML elements. The image below shows an example for the http://tardis.edu.au/datasets.xsd schema.

Limitations:

• Repeated elements are only supported in a simple way. See the repeated file boxes above: extra name and size elements are added independently to each other and the system matches them up based on position when submitted. It's not possible to duplicate several fields as a single "block", such as might be done when having several dataset subelements within a datasets element.
• It is not possible to have nested levels of repeated elements. Thefore, although we could have several dataset elements within a single datasets element (subject to the issue above), it would not be possible to have further repeating file elements under each dataset.

[edit] Object model

The limitations on nested repeating elements suggest an atomic object model, where experiments and individual datasets are contained in separate Fedora objects. This is arguably also useful from a user perspective: it would probably be overwhelming for a user to be presented with metadata for all datasets, rather than viewing/editing one at a time.

Note, however, that Fez does not currently support atomic object models! There has been discussion in the past about implementing complex objects using RELS-INT or RELS-EXT (reference needed), but currently RELS-EXT is only used to say objects are members of collections. Adding support for scientific datasets will require significant modification to Fez and it therefore seems likely that the UQ component of TARDIS will initially be hosted as a separate repository until further development effort can be coordinated with the UQ library.