[Nsi-wg] master.xml

[Jeroen van der Ham]

Hi,

On 29 Oct 2013, at 19:03, John MacAuley <john.macauley at surfnet.nl> wrote:
> I thought I would point out the master.xml on github is invalid NML and will not parse using the nmlbase.xml and nsi-ext.xsd schemas as defined.  The nsi:isReference attribute is not defined in schema, and therefore, cannot be parsed by JAXB based off the nmlbase.xml and nsi-ext.xsd schemas.

I know. I have been raising this issue before in both the NSI and NML group. The problem is that I do not know a way of including the nsi:isReference attribute in the NSI schema. I’ve asked how, but nobody seems to know.

> There are two problems with the XML as defined:
> 
> 1. There is no anyAttribute defined in the context of the Topology element from nmlbase.xml so attributes from an external namespace cannot be included.

If this is the case, then this seems to me to be a very valid change that we should try to get into the schema ASAP.

> 2. There is no isReference attribute defined in nsi-ext.xsd so it cannot be used.

See above. There is no way to define it in XML Schema AFAICT.

> If we intend to use this mechanism for an extended period of time I would suggest we formalize the required schema changes as part of topology distribution version 1.0.
> 
> I attached what I modified to get my implementation to work correctly.  These are backward compatible changes in NML, which will allow an application compiled with the new schema to read old files, however, the reverse is not true.  We should probably do an update to the standard schema once we agree on how Service Definitions get supported.

I completely agree though that this would be a stop-gap solution and that we should move to some kind of Topology Service discoverable through the NSI Discovery service.
At some point though we will have to have some kind of XML representation to describe the binding between a Topology and a URL.

Jeroen.