Use a cache of Schema.possible_types

# Gemfile
gem 'graphql-client'

require "graphql/client"
require "graphql/client/http"

# Star Wars API example wrapper
module SWAPI
  # Configure GraphQL endpoint using the basic HTTP network adapter.
  HTTP = GraphQL::Client::HTTP.new("https://example.com/graphql") do
    def headers(context)
      # Optionally set any HTTP headers
      { "User-Agent": "My Client" }
    end
  end  

  # Fetch latest schema on init, this will make a network request
  Schema = GraphQL::Client.load_schema(HTTP)

  # However, it's smart to dump this to a JSON file and load from disk
  #
  # Run it from a script or rake task
  #   GraphQL::Client.dump_schema(SWAPI::HTTP, "path/to/schema.json")
  #
  # Schema = GraphQL::Client.load_schema("path/to/schema.json")

  Client = GraphQL::Client.new(schema: Schema, execute: HTTP)
end

HeroNameQuery = SWAPI::Client.parse <<-'GRAPHQL'
  query {
    hero {
      name
    }
  }
GRAPHQL

HeroFromEpisodeQuery = SWAPI::Client.parse <<-'GRAPHQL'
  query($episode: Episode) {
    hero(episode: $episode) {
      name
    }
  }
GRAPHQL

HumanFragment = SWAPI::Client.parse <<-'GRAPHQL'
  fragment on Human {
    name
    homePlanet
  }
GRAPHQL

HeroNameQuery = SWAPI::Client.parse <<-'GRAPHQL'
  {
    luke: human(id: "1000") {
      ...HumanFragment
    }
    leia: human(id: "1003") {
      ...HumanFragment
    }
  }
GRAPHQL

module Hero
  Query = SWAPI::Client.parse <<-'GRAPHQL'
    {
      luke: human(id: "1000") {
        ...Human::Fragment
      }
      leia: human(id: "1003") {
        ...Human::Fragment
      }
    }
  GRAPHQL
end

result = SWAPI::Client.query(Hero::Query)

# The raw data is Hash of JSON values
# result["data"]["luke"]["homePlanet"]

# The wrapped result allows to you access data with Ruby methods
result.data.luke.home_planet

result = SWAPI::Client.query(Hero::HeroFromEpisodeQuery, variables: {episode: "JEDI"}, context: {user_id: current_user_id})

<%# app/views/humans/human.html.erb %>
<%graphql
  fragment HumanFragment on Human {
    name
    homePlanet
  }
%>

<p><%= human.name %> lives on <%= human.home_planet %>.</p>

>> "views/humans/human".camelize
=> "Views::Humans::Human"
>> Views::Humans::Human::HumanFragment
=> #<GraphQL::Client::FragmentDefinition>

gem 'graphql-client'