schema.ex

defmodule GostPlatformWeb.GraphQL.Schema do
  use Absinthe.Schema
  use Absinthe.Schema.Notation

  use Absinthe.Relay.Schema, :modern
  use Absinthe.Relay.Schema.Notation, :modern

  alias GostPlatform.{Vessel, Fleet}

  @fleets %{
    "123" => %Fleet{id: "123", name: "Star fleet", area: "Alpha quadrant"},
    "321" => %Fleet{id: "321", name: "US Navy", area: "All the earth oceans"}
  }

  @vessels %{
    "456" => %Vessel{id: "456", name: "USS Enterprise", designation: "NCC-1701"},
    "654" => %Vessel{id: "654", name: "USS George Washington", designation: "CVN-73"}
  }

  node object(:vessel) do
    field(:name, :string)
    field(:designation, :string)
  end

  node object(:fleet) do
    field(:name, :string)
    field(:area, :string)
  end

  node interface do
    resolve_type(fn
      (%{designation: _}, _res) ->
        :vessel
      (%{area: _}, _res) ->
        :fleet
      (qux, _res) ->
        nil
    end)
  end

  query do
    node field do
      resolve fn
        (%{type: :vessel, id: id}, _res) ->
          {:ok, Map.get(@vessels, id)}
        (%{type: :fleet, id: id}, _res) ->
          {:ok, Map.get(@fleets, id)}
        (obj, _res) ->
          {:ok, nil}
      end
    end
  end
end