GraphQL-Ruby async authorization example

aync_graphql_auth.rb

require "bundler/inline"

gemfile do
  gem "graphql", "2.4.4"
  gem "graphql-pro", "1.29.4"
  gem "async"
  gem "pundit"
end

class ThingPolicy
  def initialize(context, object)
    @object = object
    @context = context
  end

  def read?
    @context.dataloader.with(SleepSource, @object.fetch(:sleep_s)).load(@object.fetch(:name))
  end
end

class SleepSource < GraphQL::Dataloader::Source
  # IRL this would accept something like a Model class
  def initialize(sleep_duration)
    @sleep_duration = sleep_duration
  end

  # IRL this would accept the IDs that could be batched together in an external service call
  def fetch(names)
    puts "Authorizing #{names.inspect} (#{@sleep_duration})"
    sleep @sleep_duration
    puts "Finished #{names.inspect}"
    # Return a result for each passed-in value:
    names.map { true }
  end
end

class MySchema < GraphQL::Schema
  class BaseObject < GraphQL::Schema::Object
    include GraphQL::Pro::PunditIntegration::ObjectIntegration
    pundit_role :read
  end

  class Thing < BaseObject
    pundit_policy_class ThingPolicy
    field :name, String
  end

  class Query < BaseObject
    pundit_role nil
    field :thing_one, Thing, fallback_value: { name: "One", sleep_s: 1 }
    field :thing_two, Thing, fallback_value: { name: "Two", sleep_s: 2 }
  end

  # Pass the whole context as `viewer` so that you can use `context.dataloader`
  # see https://graphql-ruby.org/authorization/pundit_integration.html#custom-user-lookup
  class Context < GraphQL::Query::Context
    def pundit_user
      self
    end
  end
  context_class(Context)
  query(Query)
  use GraphQL::Dataloader::AsyncDataloader
end

pp MySchema.execute("{ thingOne { name } thingTwo { name } }").to_h
# Authorizing ["One"] (1)
# Authorizing ["Two"] (2)
# Finished ["One"]
# Finished ["Two"]
# {"data"=>{"thingOne"=>{"name"=>"One"}, "thingTwo"=>{"name"=>"Two"}}}