Clarify XSD 1.0 or 1.1 Compatibility via Schema Versioning Annotation

[peturingi]

I’d like to suggest explicitly stating the intended XML Schema version compatibility (XSD 1.0 vs 1.1) in all provided .xsd files, to clearly communicate to tool implementers which version of XSD is expected.

This can be done non-intrusively using the versioning control namespace defined in the W3C XML Schema 1.1 specification — note that this is fully XSD 1.0-compatible, as attributes from foreign namespaces are ignored by conforming processors.

Specifically, by adding the following to each xs:schema element:

xmlns:vc="http://www.w3.org/2007/XMLSchema-versioning"
vc:maxVersion="1.x"

Where x is either 0 or 1, depending on the intended compatibility.

Thanks for your work on this project!

—
Pétur

[marcphilipp]

I've read https://www.w3.org/2007/XMLSchema-versioning/ and it seems to me that this namespace is intended to be used within an XSD to mark alternative version of types etc. and not on the xs:schema element. Is this documented as a best practice elsewhere?

[peturingi]

It is done by both XMLSpy and Oxygen XML -- not to argue they are following best practises.

[marcphilipp]

Thanks for the pointers! Since I'm not aware of any issues with the current schema, I'd rather not add this attribute at this time.