lyd_parse_op behavior

[zhoujin07]

Hi,I'm running into some peculiar behavior about the leaf with identityref type while using lyd_parse_op() and I just want to check whether this is expected or not. My YANG model:

module test-1111 {
  namespace "urn:test:params:xml:ns:yang:test-1111";
  prefix tt-11;

  identity basic-type {
    description "The basic type";
  }

  identity current-type {
    base basic-type;
    description "The current type.";
  }

  rpc load-file {
    input {
      container loadfile {
        list files {
          key "name";

          leaf name {
            type string;
          }

          container file-parameters {
            leaf type {
              type identityref {
                base basic-type ;
              }
              mandatory true ;
              description "File type of load operation.";
            }
          }
        }
      }
    }
  }
}

I got three RPC Msgs: 1.

<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="24">
    <load-file xmlns="urn:test:params:xml:ns:yang:test-1111">
        <loadfile>
            <files>
                <name>test</name>
                <file-parameters>
                    <type>current-type</type>
                </file-parameters>
            </files>
        </loadfile> 
    </load-file>
</rpc>

NO prefix both in tag and content, and lyd_parse_op returns successfully. 2.

<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="24">
    <tt-11:load-file xmlns:tt-11="urn:test:params:xml:ns:yang:test-1111">
        <tt-11:loadfile>
            <tt-11:files>
                <tt-11:name>test</tt-11:name>
                <tt-11:file-parameters>
                    <tt-11:type>tt-11:current-type</tt-11:type>
                </tt-11:file-parameters>
            </tt-11:files>
        </tt-11:loadfile>
    </tt-11:load-file>
</rpc>

Prefix both in tag and content, and lyd_parse_op returns successfully. 3.

<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="24">
    <tt-11:load-file
        xmlns:tt-11="urn:test:params:xml:ns:yang:test-1111">
        <tt-11:loadfile>
            <tt-11:files>
                <tt-11:name>test</tt-11:name>
                <tt-11:file-parameters>
                    <tt-11:type>current-type</tt-11:type>
                </tt-11:file-parameters>
            </tt-11:files>
        </tt-11:loadfile> 
    </tt-11:load-file>
</rpc>

It got prefix ONLY in tag and the content got no prefix, and lyd_parse_op returns as following: libyang[0]: Invalid identityref "current-type" value - identity not found in module "ietf-netconf". (path: Data location "/test-1111:load-file/loadfile/files[name='test']/file-parameters/type", line number 1.

So, I defined current-type in test-1111.yang,why it searches it in ietf-netconf module?,is there any bugs in lyd_parse_op or just RPC Msg 3 is illegal?

[jktjkt]

The XML namespaces are "inherited" from parent elements. In your first example, the <load-file xmlns="urn:huawei:params:xml:ns:yang:huawei-system-load"> statement overrides the default namespace, while your second and third examples only "assign" this namespace to the tt-11: prefix, and the empty prefix still refers to the xmlns="urn:ietf:params:xml:ns:netconf:base:1.0".

I would have to look up the YANG RFC to say whether these default/empty namespaces affect actual element values because that's surely out-of-scope for XML itself.

[zhoujin07]

The XML namespaces are "inherited" from parent elements. In your first example, the <load-file xmlns="urn:huawei:params:xml:ns:yang:huawei-system-load"> statement overrides the default namespace, while your second and third examples only "assign" this namespace to the tt-11: prefix, and the empty prefix still refers to the xmlns="urn:ietf:params:xml:ns:netconf:base:1.0".

I would have to look up the YANG RFC to say whether these default/empty namespaces affect actual element values because that's surely out-of-scope for XML itself.

Sorry, I made a mistake, There is no huawei-system-load in xmlns.It'a all test-1111, the module name that defines the identity.I'v modified the module and RPCs,Would you check it again?

[michalvasko]

It seems the default XML namespace is used for identityref values without prefixes. I am not exactly sure why we implemented it this way (probably seemed most XML-like) but I see no reason to change. You can try to write to the netmod mailing list to learn how it is supposed to be interpreted exactly, I could find no clear definition in the YANG RFC.

[zhoujin07]

It seems the default XML namespace is used for identityref values without prefixes. I am not exactly sure why we implemented it this way (probably seemed most XML-like) but I see no reason to change. You can try to write to the netmod mailing list to learn how it is supposed to be interpreted exactly, I could find no clear definition in the YANG RFC.

OK,Got it.Thanks for the comment.