We have found some issues with RPC XPaths when developing the YANG code for 
https://tools.ietf.org/html/draft-ietf-teas-yang-path-computation

As discussed during the TEAS WG session in IETF 108, this issue has been raised 
on pyang github: https://github.com/mbj4668/pyang/issues/662

It was also suggested to check with Netmod WG what should be the correct 
behavior according to RFC7950.

The following code is accepted by pyang 1.75 but not by pyang 2.1:

    type leafref {
      path "/te:tunnels-path-compute/te:input/"
         + "te:path-compute-info/"
        + "te-pc:tunnel-attributes/te-pc:tunnel-name";
    }

The following code instead is accepted by pyang 2.1 but not by pyang 1.7.5:

    type leafref {
      path "/te:tunnels-path-compute/"
         + "te:path-compute-info/"
        + "te-pc:tunnel-attributes/te-pc:tunnel-name";
    }

Moreover the following when statement, which is quite useful to constraint 
which information is provided by the RPC output based on some attributes in the 
RPC input, is accepted by pyang 1.7.5 but not accepted by pyang 2.1;

  augment "/te:tunnels-actions/te:output" {
    description
      "Augment Tunnels Action RPC input with path delete result";

    container path-computed-delete-result {
      when "derived-from-or-self(../../te:input/te:action-info/"
         + "te:action, 'tunnel-action-path-compute-delete')";
      description "Path Delete RPC output";
      leaf-list path-compute-transaction-id {
        type string;
        description
          "The list of the transaction-id values of the
           transient states that have been successfully deleted";
      }
    }   // container path-computed-delete-result
  }   // path-delete rpc output


Could you please help us to understand what is the correct behavior?

In case the correct behavior is the one of pyang 2.1, our understanding is that 
it would not be possible to provide in YANG when constraints for the data nodes 
in the RPC output depending on specific values of the data nodes used in the 
RPC input. Therefore these constraints should be specified as behavior and 
implemented in the back-end.

Is our understanding correct?

Thanks for your help

Sergio and Italo (on behalf of co-authors/contributors)

Italo Busi
Principal Optical Transport Network Research Engineer

[cid:[email protected]]
____________________________________________________________________

Huawei Technologies Italia S.r.l.
Address: Centro Direzionale Milano 2, Palazzo Verrocchio, 20090 Segrate (MI)
Tel: +39 345 4721946 - Mobile: 
[email protected]<mailto:[email protected]>

__________________________________________________________________________________
Huawei Technologies Italia S.r.l. is a company registered in Italy at the 
Company Registration Office of Milan, with registered number 04501190963 and 
equity capital €3,000,000 fully paid up, whose registered office is in Milan, 
Via Lorenteggio 240, Tower A, 20147 Milan, Italy. Huawei Technologies Italia 
S.r.l. is 100% owned by Huawei Technologies Cooperatief U.A.
CONAI Reg. No. cc 12639454 - A.E.E. Registry No. IT10010000006521 - Batteries 
and Accumulators Registry No. IT12050P00002839.
________________________________________________________________________________________________________________________
This e-mail and its attachments contain confidential information from HUAWEI, 
which is intended only for the person or entity whose address is listed above. 
Any use of the information contained herein in any way (including, but not 
limited to, total or partial disclosure, reproduction, or dissemination) by 
persons other than the intended recipient(s) is prohibited. If you receive this 
e-mail in error, please notify the sender by phone or email immediately and 
delete it! Thank you.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
PRIVACY NOTICE: Pursuant to Art. 13 of the General Data Protection Regulation 
2016/679 (GDPR), Huawei Technologies Italia S.r.l. informs you that the 
personal data contained in this email will be collected and treated for the 
acquisition of information preliminary to the conclusion of contracts, for the 
definition of the contractual relationship, as well as for the fulfillment of 
legal requirements related to civil, tax and accounting law or any other legal 
obligation to which Huawei may be subject. Personal data will not be subject to 
disclosure and spread unless otherwise required by law. Huawei will take 
appropriate security measures to protect personal data against loss, misuse 
disclosure or destruction of the information. Personal Data held may be 
transferred to countries outside the European Union, however Huawei Italia has 
put in place appropriate safeguards for the transfer of personal data to third 
countries by adopting the standard data protection clauses of the EU 
Commission. Personal Data are kept for a period necessary for the fulfillment 
of contract obligations unless otherwise required by law. You can exercise your 
rights under Art. 15 and following of the GDPR (i.e. right of access, 
rectification, erasure, restriction, portability, object) by contacting Huawei 
at this email address: 
[email protected]<mailto:[email protected]> or through the 
following channel: 
www.huawei.com/en/personal-data-request<http://www.huawei.com/en/personal-data-request>.
 You have also the right to lodge a complaint with the competent supervisory 
authorities. If you need any further information or have any queries on how 
Huawei process your personal data, please send an email to our Data Protection 
Officer at [email protected]<mailto:[email protected]>.The Data Controller is 
Huawei Technologies Italia S.r.l. with registered office in Milan, Via 
Lorenteggio 240 Tower A, 20147.


_______________________________________________
netmod mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/netmod

Reply via email to