GraphqlLazyLoad

Lazy executor for activerecord associations and graphql gem.

Installation

GraphqlLazyLoad requires ActiveRecord >= 4.1.16 and Graphql >= 1.3.0. To use add this line to your application's Gemfile:

gem 'graphql_lazy_load'

Then run bundle install.

Or install it yourself as:

$ gem install graphql_lazy_load

Usage

To use, first add the executor (GraphqlLazyLoad::ActiveRecordRelation) to graphqls schema:

class MySchema < GraphQL::Schema
  mutation(Types::MutationType)
  query(Types::QueryType)

  lazy_resolve(GraphqlLazyLoad::ActiveRecordRelation, :result)
end

Now you can start using it! Wherever you have an association, the syntax is:

field :field_name, Types::AssociationType, null: false
def field_name
  GraphqlLazyLoad::ActiveRecordRelation.new(self, :association_name)
end

Examples

If you have two models Team which can have many Players. To lazy load players from teams do the following:

module Types
  class PlayerType < Types::BaseObject
    ...
    field :players, [Types::PlayerType], null: false
    def players
      GraphqlLazyLoad::ActiveRecordRelation.new(self, :players)
    end
  end
end

And to lazy load teams from players do the following:

module Types
  class TeamType < Types::BaseObject
    ...
    field :team, Types::TeamType, null: false
    def team
      GraphqlLazyLoad::ActiveRecordRelation.new(self, :team)
    end
  end
end

Scoping

The great thing about GraphqlLazyLoad::ActiveRecordRelation is it allows scopes to be passed! So for the example above if you want to allow sorting (or query, paging, etc) do the following.

module Types
  class PlayerType < Types::BaseObject
    ...
    field :players, [Types::PlayerType], null: false do
      argument :order, String, required: false
    end
    def players(order: nil)
      scope = Player.all
      scope = scope.sort(order.underscore) if order
      GraphqlLazyLoad::ActiveRecordRelation.new(self, :players, scope: scope)
    end
  end
end

To test this out try the example app at graph_test

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/jonathongardner/graphql_lazy_load. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the GraphqlLazyLoad project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.