Hi Balazs, I agree with you, we need a machine-readable offline specification of the entire schema. After Martin returns from his vacation, I plan to discuss this with him.
Some comments are inline. Balazs Lengyel <[email protected]> writes: > Hello, > > As I understand it, Schema-mount today does not support an important > use-case which we definitely need, but others also indicated they > want. > > I want to specify off-line in design time which models will be mounted > where. Many of my nodes know in design-time what their model structure > will be, so I want a way to be able to document this in YANG. In > today's proposal the only way to find the Yang-Mounts is to read it > from the live node. > > * OAM integrators or operators want to be able to write CLI scripts > and Netconf messages without accessing (expensive) real nodes. For > this they need to know the mounts > * We want to generate some fancy documentation from YANG automatically > in design-time. In fact, I met several people in Berlin that expect to be able to standardise data models utilising schema-mount. > > * Many use cases need the possibility to mount schemas, but do not > need the added complexity of schema changes in run-time. > Notwithstanding the case of "YANG Features", for me the model schema > is a mostly static description of a nodes capabilities. Most of the > time I do not want to worry about the node changing its schema on > the fly. > > > For this I propose 2 YANG extensions > > extension schema-mount { > description "Indicates that a YANG Module is to be mounted into > another module. > The argument specifies the name of the module to be mounted."; > argument mounted-module; > } > > extension schema-mount-target { > description "Specifies the target node under which a YANG module is to > be mounted. > The statement can only be used inside a schema-mount statement. > The argument follows the same rules as an augment statement's target. > argument target-node; > } This looks similar to the RELAX NG "external" pattern that I briefly described in slide 9 of my presentation in Berlin: https://www.ietf.org/proceedings/96/slides/slides-96-netmod-7.pdf However, I am not in favour of introducing extesions for such fundamental data modelling functions because doing so undermines the value of YANG as a standard. That's why I would prefer to use a solution based on a meta-schema language (see my slide 10). After all, YANG library in fact already is a meta-schema language, so we could just extend it to support schema mount. Lada > > The two extension statements can be placed in a separate module or the > mounted module. > > I don't insist on the solution, but I need the off-line/design-time > specification of yang-mount to be possible. IMHO the design-time mount > use-case is more important than the dynamic-mount. > > regards Balazs > -- > Balazs Lengyel Ericsson Hungary Ltd. > Senior Specialist > Mobile: +36-70-330-7909 email: [email protected] > _______________________________________________ > netmod mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/netmod -- Ladislav Lhotka, CZ.NIC Labs PGP Key ID: E74E8C0C _______________________________________________ netmod mailing list [email protected] https://www.ietf.org/mailman/listinfo/netmod
