> On 16 Sep 2015, at 18:00, Andy Bierman <a...@yumaworks.com> wrote: > > > > On Wed, Sep 16, 2015 at 8:17 AM, Juergen Schoenwaelder > <j.schoenwael...@jacobs-university.de> wrote: > On Tue, Sep 15, 2015 at 12:21:44PM -0700, Andy Bierman wrote: > > On Tue, Sep 15, 2015 at 12:01 PM, Randy Presuhn < > > randy_pres...@mindspring.com> wrote: > > > > > Hi - > > > > > > >From: Juergen Schoenwaelder <j.schoenwael...@jacobs-university.de> > > > >Sent: Sep 14, 2015 11:41 PM > > > >To: Ladislav Lhotka <lho...@nic.cz> > > > >Cc: NETMOD Working Group <netmod@ietf.org> > > > >Subject: Re: [netmod] Fwd: New Version Notification for > > > draft-ietf-netmod-yang-json-05.txt > > > ... > > > >My question is why the text is silent about the case where the data > > > >model is present. Should it not say that if the data model is present, > > > >the data encoded inside the anydata node must follow the rules of this > > > >document? Perhaps this is the implicit assumption but I think it will > > > >be useful to say this explicitly (if we agree on this). > > > > > > > >If the data model is not present, then I think an implementation is > > > >still expected to produce an encoding that follows the rules of this > > > >document as much as possible except that things that requires data > > > >model knowledge may be encoded differently (e.g., numbers appearing as > > > >strings or namespace names being different). I am thinking along the > > > >lines of this proposed new text: > > > > > > > > An anydata data node can contain an unknown set of nodes that can > > > > be modelled by YANG. A data model for anydata content may or may > > > > not exist at run time. If the data model for anydata content is > > > > available, then the anydata content MUST be encoded according to > > > > the rules of this specification. If the data model for anydata > > > > content is not available, the encoding MUST follow the rules of > > > > this specification except for rules that require data model > > > > knowledge (and as a consequence, numbers may appear as strings or > > > > namespace qualifiers may not match module names). > > > > > > This leaves me wondering what it means for the data model for > > > anydata content to be "available". In the case of ASN.1's > > > "ANY DEFINED BY" construct, there's an OBJECT IDENTIFIER to > > > unambiguously identify the grammar (and associated semantics) > > > to be used to understand the content, so tools can, if needed, > > > scurry off to obtain the parsing instructions for those > > > particular bits. How does an implementation know in the case > > > of "anydata" which datamodel to use? > > > > > > > > Good questions.... > > The text "If the data model for anydata content is available" gives a hint > > of just > > what a hack anydata is in YANG. The definition of anydata is that there is > > no data model for the specified subtree. The mere mention of an out-of-band > > data mode is inappropriate and confusing. > > > > I understand this is intended to support usage like in YANG Patch, where the > > description-stmt of 'value' says that the child node must follow the schema > > for the node in the target leaf. More hacks to get YANG to work. > > You are welcome to provide fixes. > > > OLD: > > > An anydata data node can contain an unknown set of nodes that can > be modelled by YANG. A data model for anydata content may or may > not exist at run time. If the data model for anydata content is > available, then the anydata content MUST be encoded according to > the rules of this specification. If the data model for anydata > content is not available, the encoding MUST follow the rules of > this specification except for rules that require data model > knowledge (and as a consequence, numbers may appear as strings or > namespace qualifiers may not match module names). > > > NEW: > > An anydata data node can contain an unknown set of nodes that can > be modelled by YANG.
This text is essentially in 6020bis, I see no need to repeat it. > > > The YANG RFC itself should be silent about data-model specific > semantics that are added to an anydata subtree. The text "if available" > is especially non-enforceable and therefore pointless. > I must admit I am getting lost in these discussions. It seems to me there is a lot of hand-waving and hidden assumptions that moreover differ from one person to another. As I already said in Prague, both anyxml and anydata are IMO constructs of marginal utility and it is frustrating we spend so much effort on them. Lada > > > > Once again we confuse conformance to YANG with conformance to > > a module written in YANG. The YANG Patch text can make additional > > requirements for conformance to YANG Patch. This is quite different > > than generic conformance to RFC6020bis. > > I do not think that we confuse conformance to YANG with conformance to > a module written in YANG. > > /js > > > Andy > > > -- > Juergen Schoenwaelder Jacobs University Bremen gGmbH > Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany > Fax: +49 421 200 3103 <http://www.jacobs-university.de/> > > _______________________________________________ > netmod mailing list > netmod@ietf.org > https://www.ietf.org/mailman/listinfo/netmod -- Ladislav Lhotka, CZ.NIC Labs PGP Key ID: E74E8C0C _______________________________________________ netmod mailing list netmod@ietf.org https://www.ietf.org/mailman/listinfo/netmod
