> > Michal Vaško <[email protected]> wrote: > > > > Michal Vaško <[email protected]> wrote: > > > > > Hello, > > > > > > I would like to get some input for a use-case I came across, which > > > > > > to> > > > > > > me does not seem to have any consistent rules that can be applied. > > > > > > module mod_b { > > > > > namespace "x:example:mod_b"; > > > > > prefix "mb"; > > > > > > grouping mylist_wrapper { > > > > > list mylist { > > > > > key "name"; > > > > > unique "value"; > > > > > leaf name { > > > > > type string; > > > > > } > > > > > leaf value { > > > > > type uint32; > > > > > } > > > > > } > > > > > } > > > > > > list mylist2 { > > > > > key "a"; > > > > > leaf a { > > > > > type string; > > > > > } > > > > > leaf b { > > > > > type string; > > > > > } > > > > > } > > > > > } > > > > > > > module mod_a { > > > > > namespace "x:example:mod_a"; > > > > > prefix "ma"; > > > > > > import mod_b { prefix "mb"; } > > > > > > container root { > > > > > uses mb:mylist_wrapper; > > > > > } > > > > > > augment /mb:mylist2 { > > > > > leaf c { > > > > > type string; > > > > > } > > > > > } > > > > > > deviation /mb:mylist2 { > > > > > deviate add { > > > > > unique "mb:b c"; > > > > > } > > > > > } > > > > > } > > > > > > The focus is on the "unique" statements and how to resolve > > > > > non-prefixed identifiers. RFC 7950 says that the argument is a "list > > > > > of schema node identifiers"[1], which use "current module" for > > > > > non-prefixed identifiers[2]. I have asked on this mailing list a few > > > > > years back what current module means and the answer I got was the> > > > > > > > module where the statement is defined. > > > > > > So let's get to the examples. As they are written, the unique in > > > > > "mylist" should be wrong because the node "value" belongs to the > > > > > module "mod_a" when the grouping is instantiated there, but unique is> > > > > > defined in the module "mod_b". > > > > > > But even if we use the other understanding of current module and > > > > > interpret is as the module of the context node of the statement > > > > > (corresponds to the "current()" XPath function), then the other > > > > > "unique" in the deviation cannot be resolved. It is referencing node > > > > > "c", which belongs to the module "mod_a" (added by an augment) but the > > > > > current module would then be "mod_b". > > > > > > To summarize, if strictly following the specs, the "unique" in the > > > > > "mylist" should probably reference "value" with a prefix, but that is> > > > > > not possible because "mod_a" is not even imported and it generally > > > > > does not make sense. But then I cannot think of any consistent rule to > > > > > successfully resolve both "unique" statements in this example. Can > > > > > anyone help me with this, please? > > > > > > Compare with this: > > > > > > grouping mylist_wrapper { > > > > list mylist { > > > > key "name"; > > > > unique "value"; > > > > must "value > 42"; > > > > leaf name { > > > > type string; > > > > } > > > > leaf value { > > > > type uint32; > > > > } > > > > } > > > > } > > > > > > I think the rules for the prefixes in "unique" should be the same as > > > > for "must". So I think that the correct syntax is to not use any > > > > prefix in "unique". > > > > > > And the deviation that adds a unique statement look correct. > > > > Thanks for the reply but I do not think you have answered my > > > question. Please formulate a formal rule how to assign modules to > > > non-prefixed identifiers, whether they be in "unique", "must", or any> > > > other statement with identifiers. That is what I need to implement it> > > > properly and I am simply not able to come up with any that would be > > > consistent and compliant with the specification. > > > > Interpret the unique argument the same way as an XPath expression, and > > apply (from 6.4.1): > > > > o Names without a namespace prefix belong to the same namespace as > > the identifier of the current node. Inside a grouping, that > > namespace is affected by where the grouping is used > > > > So "value" in the unique statement will refer to "value" in "mod_a" > > when the grouping is used in "mod_a". > > I see. Okay, this should be possible to implement, thanks.
I was too hasty with the reply, this is not working because of the "unique" in the deviation I have in the example. What is the "current node" in that case? I suppose that can only be "mylist2", so the namespace will be that of "mod_b". But this is wrong, the "c" node belongs to "mod_a", so the "unique" in the deviation would be wrong. > > /martin > > > > > > > /martin > > > > > > > Finally, I am asking because I am trying to implement this > > > > > > > correctly > > > > > in yanglint. I have also tried to test these examples with pyang,> > > > > > > > which, however, seems to not have any consistent rules applied > > > > > because > > > > > it loads these examples without warnings. No warnings are printed even > > > > > if the "unique" in the deviation is changed to "b c", which is > > > > > definitely wrong since node "b" belongs to "mod_b" and node "c" > > > > > belongs to "mod_a". > > > > > > Thanks, > > > > > Michal > > > > > > [1] https://datatracker.ietf.org/doc/html/rfc7950#section-7.8.3> > > > > > > > > [2] https://datatracker.ietf.org/doc/html/rfc7950#section-6.5 > > > > > > _______________________________________________ > > > > > netmod mailing list > > > > > [email protected] > > > > > https://www.ietf.org/mailman/listinfo/netmod > > _______________________________________________ > netmod mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/netmod _______________________________________________ netmod mailing list [email protected] https://www.ietf.org/mailman/listinfo/netmod
