starwars-graphql.exs

defmodule Character do
  use GraphQL.ObjectInterface

  field :id, null: false
  field :name
  field :friends, type: List.of(Character)
  field :appearsIn, type: List.of(Episode)
end

defmodule Human do
  use GraphQL.Object, deriving: Character

  field :homePlanet
end

defmodule Droid do
  use GraphQL.Object, deriving: Character

  field :primaryFunction
end

defmodule Schema do
  use GraphQL.Schema

  field :hero, type: Character do
    argument :episode, description: "foo"
    
    resolve %{episode: episode} do
      getHero(episode)
    end

    resolve do
      getHero(1000)
    end
  end

  field :human, type: Human do
    argument :id, description: "id of the human", null: false
    
    resolve %{id: id} do
      getHuman(id)
    end
  end

  field :droid, type: Droid do
    argument :id, description: "id of the droid", null: false
    
    resolve %{id: id} do
      getDroid(id)
    end
  end

  

  @humans [ 
    "1000": %Human{
      id: "1000",
      name: "Luke Skywalker",
      friends: ["1002", "1003", "2000", "2001"],
      appearsIn: [4, 5, 6],
      homePlanet: "Tatooine",
    },
    "1001": %Human{
      id: "1001",
      name: "Darth Vader",
      friends: [ "1004" ],
      appearsIn: [ 4, 5, 6 ],
      homePlanet: "Tatooine",
    },
    [ ... ]
  ]

  @droids [ ... ]

  defp getHero(5), do: @humans["1000"]
  defp getHero(_), do: @droids["2001"]
  
  defp getHuman(id), do: @humans[id]

  defp getDroid(id), do: @droids[id]
end