schema.rb

# Create user type
UserType = GraphQL::ObjectType.define do
  name 'User'
  description 'Our user model/type for GraphQL'
  
  # specify what fields this type has
  field :id, !types.ID
  field :email, !types.String
  field :username, !types.String
end

# Specify what queries our graphQL end point has
QueryType = GraphQL::ObjectType.define do
  name 'Query'
  description 'The root of all queries'
  
  # query 1
  # take an ID and return a user
  field :user do
    type UserType
    argument :id, !types.ID
    description 'The user with a given ID'
    resolve -> (obj, args, ctx) { User.find(args[:id]) }
  end

  # query 2
  # return all users
  field :allUsers do
    type types[UserType]
    description 'All users in the DB'
    resolve -> (obj, args, ctx) { User.all }
  end
end

# setup Schema
Schema = GraphQL::Schema.define do
  query QueryType
end