No commit activity in last 3 years
No release in over 3 years
Provide logic for select only required fields from query
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
 Dependencies

Development

~> 2.2
~> 1.16
~> 10.0
~> 10.0
~> 3.0
>= 1.3.13, ~> 1.3

Runtime

 Project Readme

Cult Of Martians Gem Version Build Status

GraphQL::SmartSelect

Plugin for graphql-ruby which helps to select only the required fields from the database.

Requirements

  • Ruby >= 2.3.0
  • graphql-ruby ~> 1.8.7
  • activerecord >= 4.2

Installation

Add this line to your application's Gemfile:

gem 'graphql-smart_select'

The Problem

Consider the following query:

query {
  posts {
    id
    title
  }
}

Ruby interface for serving this query:

module GraphqlAPI
  module Types
    class Query < GraphQL::Schema::Object
      field :posts, Types::Post, null: false

      def posts
        Post.all
      end
    end
  end
end

In the default case, this leads to the query: SELECT * FROM posts, and we only need id and title. For tables with a large number of columns, this could have a negative effect on performance (due to both DB reads and ActiveRecord object instantiation).

Usage

Smart Select works as an extension for field_class:

module GraphqlAPI
  module Types
    class Query < GraphQL::Schema::Object
      # use plugin
      field_class.prepend(GraphQL::SmartSelect)

      # activate plugin
      field :posts, Types::Post, null: false, smart_select: true

      # You can also explicitly specify which fields
      # to include in every query
      field :posts, Types::Post, null: false, smart_select: [:id]

      def posts
        Post.all
      end
    end

    class Post < GraphQL::Schema::Object
      field_class.prepend(GraphQL::SmartSelect)

      field :id, ID
      field :title, String
      field :raw_content, String
      field :another_content, String
  
      # We'll tell the plugin which fields are needed
      # for resolve this field
      field :contents, db_columns: [:raw_content, :another_content]
      
      # For one_to_one AR assosiation we include foreign_key
      field :user, Types::User

      # For has_many AR assosiation we include primary_key
      field :comments, [Types::Comment]

      def contents
        [object.id, object.title].join
      end
    end
  end
end

For this example query:

query {
  posts {
    title
    contents
    user { name }
    comments { id }
  }
}

It performs the following query: SELECT id, title, raw_content, another_content, user_id FROM posts

Notes

Custom Resolvers are not supported.

Tested for activerecord version >= 4.2

Development

For regression testing, run the following

# install Appraisals dependencies
bundle exec appraisal install
# run test suit through all dependencies listed in Appraisals file
bundle exec appraisal rake spec

License

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