[netmod] mandatory choice with non-presence container case

Michal Vaško <mvasko@cesnet.cz> Mon, 24 June 2019 16:39 UTC

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Date: Mon, 24 Jun 2019 18:39:18 +0200
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Subject: [netmod] mandatory choice with non-presence container case
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Hi,
I have encountered a situation that I think is not covered by RFC 7950. My specific use-case was as follows.

model:

container TOP {
  leaf L {
    type empty;
  }
  choice A {
    mandatory true;
    container C;
  }
}

data:

<TOP>
  <L/>
  <C/>
</TOP>

Parsing was successful, but printing these data back to XML produced:

<TOP>
  <L/>
</TOP>

and parsing this correctly failed with missing mandatory choice. According to section 7.5.7 [1], I think the C container could be omitted but the whole situation does not seem correct. Thank you for any input.

Regards,
Michal

[1] https://tools.ietf.org/html/rfc7950#section-7.5.7