emix — archive

Hot Topic: Namespaces and Versioning

From: William Cox <[email protected]>
To: [email protected]
Date: Sun, 12 Jun 2011 17:18:00 -0000

Detailed thoughts below. This follows the W3 conventions quite well (except where they seem to think that there is one version per year). Summary: Approach 2, adding /06 for the current schemas and namespace. URI for the schemas themselves is determined by the TC Admin. Plain namespace (without the date) seems to always dereference to the latest namespace document. This is useful, but not to program with. Thanks! bill -- William Cox Email: [email protected] Web: http://www.CoxSoftwareArchitects.com +1 862 485 3696 mobile +1 908 277 3460 fax On 6/12/11 11:00 AM, Toby Considine wrote: [email protected] type= cite > We have yet to deal completely with Schema and namespace versioning. (1) One approach would look like the following: NO. Has the problem that it assumes one version per year. [email protected] type= cite > Table 1 €‘1: XML Namespaces in this standard Prefix Namespace emix: http://docs.oasis-open.org/ns/emix/2011 siscale http://docs.oasis-open.org/ns/emix/siscale/2011 power: http://docs.oasis-open.org/ns/emix/power/2011 resource: http://docs.oasis-open.org/ns/emix/power/resource/2011 (2) An alternate approach would look like YES with the changes shown - adding /06 to each. There is an issue about the subnamespaces (thinking in URI-speak) as to whether they would have their own Namespace document or a copy of that for the top; it's also been suggested that in parallel, the first namespace should end with emix/ -- since the overall namespace is emix, I don't think that's needed. Also, I believe (trivial issue) that the prefix does not include the : but instead is separated from the reference by : - in any event it should be consistent so it's not emix: and siscale ... [email protected] type= cite > Table 1 €‘1: XML Namespaces in this standard Prefix Namespace emix: http://docs.oasis-open.org/ns/emix/2011/06/ siscale http://docs.oasis-open.org/ns/emix/2011/06/siscale power: http://docs.oasis-open.org/ns/emix/2011/power resource: http://docs.oasis-open.org/ns/emix/2011/power/resource (3) Still another, which we seem to have adopted implicitly is NO. Need year/data in the namespace, unless it's perfect and we'll never ever have another version :-) [email protected] type= cite > Table 1 €‘1: XML Namespaces in this standard Prefix Namespace emix: http://docs.oasis-open.org/ns/emix/ siscale http://docs.oasis-open.org/ns/emix/siscale power: http://docs.oasis-open.org/ns/emix/power resource: http://docs.oasis-open.org/ns/emix/power/resource There are then the various approaches which summarize as €œputting v1.0 in place of the 2011 in alternates (1) and (2) This is confusing similar to but not identical to the similar issue of persistence of artifacts. In general, I recommend that we remain consistent with W3C Guidelines which are oft-quoted as follows: <xs:annotation> <xs:documentation>In keeping with the XML Schema WG's standard versioning policy, this schema document will persist at http://www.w3.org/2005/08/xml.xsd . At the date of issue it can also be found at http://www.w3.org/2001/xml.xsd . The schema document at that URI may however change in the future, in order to remain compatible with the latest version of XML Schema itself, or with the XML namespace itself. In other words, if the XML Schema or XML namespaces change, the version of this document at http://www.w3.org/2001/xml.xsd will change accordingly; the version at http://www.w3.org/2005/08/xml.xsd will not change. </xs:documentation> </xs:annotation> This would result in a statement as follows: In keeping with the XML Schema WG's standard versioning policy, the schemas defined in this specification will persist in http://docs.oasis-open.org/ns/emix/2011/06/ . At the date of issue, each can also be found at http://docs.oasis-open.org/ns/emix/2011/ . The schema documents at that URI may however change in the future, in order to remain compatible with the latest version of EMIX Specification. In other words, if the schemas namespaces change, the version of these document at http://docs.oasis-open.org/ns/emix/2011/ will change accordingly; the versions at http://docs.oasis-open.org/ns/emix/2011/06/ will not change. I don't like this at all. Then if we do 1.1 in September, then does 2011 get updated? This seems to lead to confusion. Seems very bad to have that be the case.. In any event, the OASIS rules and the TC Admin determine the artifact location. For example, EMIX PR02 (CSPRD02) artifacts (XSD) are at http://docs.oasis-open.org/emix/emix/v1.0/csprd02/xsd/ and referenced by the namespace document at http://docs.oasis-open.org/ns/emix (NOTE no final / ) It does appear that there is no structure below that namespace that's easily discoverable; the base namespace is there for emix, ws-calendar, etc, and gives the most recent versions. So the namespace ending with ...emix would give you the latest; referencing the actual date gives you that version. As I said, I'm not sure whether the emix namespace is useful except to find the particular namespace defined and the schemas. [email protected] type= cite > €œThe single biggest problem in communication is the illusion that it has taken place. € €“ George Bernard Shaw. Toby Considine TC9, Inc TC Chair: oBIX & WS-Calendar TC Editor: EMIX, EnergyInterop U.S. National Inst. of Standards and Tech. Smart Grid Architecture Committee Email: [email protected] Phone: (919)619-2104 http://www.tcnine.com/ blog: www.NewDaedalus.com