Upgrading Registries for VODataService 1.1 and its extensions (2013)

The VODataService v1.1 registry extension was passed as a Recommendation in 2010. This deprecated the working draft extension v1.0. Since then, two additional extensions have been passed which augment VODataService v1.1:

• TAPRegExt v1.0 (2012): for describing TAP services
• SimpleDALRegExt v1.0 (2013): formalizes the extensions for our four main Simple DAL service protocols, deprecating previous working draft versions

As of this writing, there are registries serving up resource records that still use VODataService 1.0 and the now-deprecated DAL extensions. This page is intended to help registry administrators upgrade these records.

It is worth noting that the Registry Framework is flexible enough to allow the use of different versions of the VOResource extension schemas (as long as their versions are properly indicated), and today we have VODataService 1.0 and 1.1 records living side by side in peace and harmony. Nevertheless, interoperability is easier when we all use the same version--that is, consumers need only look in one place to find a piece of metadata.

XSL Stylesheets for upgrading records.

We have created an XSL stylesheet that will convert records using VODataService v1.0 and its dependent DAL extensions and convert them to use the latest schema. (It will also convert TAP records identified only by their standardID--i.e. that do not provide any extension metadata--to use TAPRegExt.)

• VODSupgrade.xsl2

This stylesheet requires an XSLT 2.0 processor, such as the Saxon engine, available in saxon8.jar. To run, type:

java -jar saxon8.jar resource.xml VODSupgrade.xsl2 > resource-upg.xml

where resource.xml is the resource record to convert.

Note that you can safely process any VOResource document with this stylesheet, regardless of whether it needs converting or not. If it finds no deprecated schemas in use, the record will pass unchanged (though spacing may be neatened up, `cause I can't help myself).

Note that in the transition from the deprecated versions to the latest ones, one feature that changed is what elements are required, which are optional, and what their defaults are. When an input record appears to contain a "default" value, the element may be removed. Similarly, when an element needs to be added, some assumptions are made about the ne values that are inserted. You may want to review a sampling of converted records to see if these choices appear appropriate.