Are union types supported?

[billy1kaplan]

Thanks for your hard work on this, this looks awesome!

I was curious of union types are supported (e.g. anyOf in JSON Schema or xsd:choice in XSD).

[kgiszczak]

Hey, sorry for such a delay. They are supported when you generate models from the schema e.g.

json = <<~DATA
{
  "type": "object",
  "properties": {
    "firstName": {
      "anyOf": [
        { "type": "string" },
        { "type": "number" }
      ]
    },
    "lastName": {
      "type": "string"
    }
  }
}
DATA

puts Shale::Schema.from_json([json]).values[0]

firstName attribute will have a type of Shale::Type::Value meaning it will accept anything and won't type cast:

require 'shale'

class Root < Shale::Mapper
  attribute :first_name, Shale::Type::Value
  attribute :last_name, Shale::Type::String

  json do
    map 'firstName', to: :first_name
    map 'lastName', to: :last_name
  end
end

In XML schema ,xs:choice has a different meaning:

xml = <<~DATA
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="Person">
    <xs:complexType>
      <xs:choice>
        <xs:element name="FirstName" type="xs:string"/>
        <xs:element name="LastName" type="xs:string"/>
      </xs:choice>
    </xs:complexType>
  </xs:element>
</xs:schema>
DATA

puts Shale::Schema.from_xml([xml]).values[0]

it will give you:

class Person < Shale::Mapper
  attribute :first_name, Shale::Type::String
  attribute :last_name, Shale::Type::String

  xml do
    root 'Person'

    map_element 'FirstName', to: :first_name
    map_element 'LastName', to: :last_name
  end
end

If you want to generate schema from models, they are not supported as there is no way to mark attributes as belonging to union.

[kgiszczak]

Hey, Im closing this issue, if you have any other questions, let me know.