Unnamed union with named members on the model level

[Pawel Kowalik (pawel-kow)]

Hi,

I am trying to model the following:
foo has a property bar and one of 2 properties baz and fox.

I tried the following, but I'm getting "Cannot spread properties of non-model type."

model foo {
  bar: uint32;
  ...baz_or_fox;
}

union baz_or_fox {
  baz: uint32;
  fox: uint32;
} 

I could use xxx: baz_or_bar but this would create a nested property xxx that I would not want.

Any suggestion how this can be done?

[Timothee Guerin (timotheeguerin)]

this is not possible with the current syntax. Closest you can do is creating foo as a union of the 2 variants and spread the common properties

[Pawel Kowalik (pawel-kow)]

Ok, pity. The proposal kind of works but feels like a bit of a hack.

union foo {
    foo_baz | foo_fox
}

model foo_common {
    bar: uint32;
}

model foo_baz extends foo_common {
    baz: uint32;
}

model foo_fox extends foo_common {
    fox: uint32;
}

And if I'm not mistaken the approach won't work if there would be more than one such pairs baz | fox.

Is there any similar feature request or where would be an appropriate place to place one?

[Timothee Guerin (timotheeguerin)]

kinda included in this general design #961 but more as a validation based approach

the problem with the approach you have is, its not really something that most language can represent so that value is much more limited.

That syntax could maybe be considered as a syntactic sugar for some validation I guess, feel free to comment on it with the use case.

[Pawel Kowalik (pawel-kow)]

I'm trying to model the structure of dsOrKeyType type from rfc5910.

Related xsd below (for xml, but I am modelling for JSON). If I'd do JSON Schema for it manually it would be a combination of nested allOf and oneOf.

     <complexType name="dsOrKeyType">
       <sequence>
         <element name="maxSigLife" type="secDNS:maxSigLifeType"
         minOccurs="0"/>
         <choice>
           <element name="dsData" type="secDNS:dsDataType"
           maxOccurs="unbounded"/>
           <element name="keyData" type="secDNS:keyDataType"
           maxOccurs="unbounded"/>
         </choice>
           </sequence>
     </complexType>