Lighthouse GraphQL Rails

A framework for serving GraphQL from Ruby on Rails

📜 SDL First

Describe your API in the GraphQL Schema Definition Language and add behaviour with server-side directives, instead of a resolver class for every field.

🛤️ Rails Friendly

Built on graphql-ruby for an existing Rails app. Your models, scopes, validations, Pundit policies and Rails.cache keep doing their jobs.

⚡ Optimized for Active Record

Relationships and pages load in batches through the Dataloader, so a list of 100 posts with their authors and comments is a handful of queries.

Boilerplate-free schema definition

Define your schema without any boilerplate, using the GraphQL Schema Definition Language.

type User {
  name: String!
  posts: [Post!]! @hasMany(type: PAGINATOR)
}

type Post {
  title: String!
  author: User! @belongsTo
}

type Query {
  me: User @guard
  posts(orderBy: [PostOrderByClause!] @orderBy): [Post!]! @paginate(defaultCount: 10)
}

type Mutation {
  createPost(input: CreatePostInput! @spread): Post!
    @guard
    @canModel(ability: "create")
    @create
    @inject(context: "current_user.id", name: "author_id")
}

Get going in minutes

Add the gem, run the installer, and query the schema it generates.

bundle add lighthouse-graphql
bin/rails generate lighthouse:install

curl localhost:3000/graphql -H 'Content-Type: application/json' \
  -d '{"query": "{ users { data { id name } paginatorInfo { total } } }"}'

Ruby where there is real logic

A Query or Mutation field without a resolving directive resolves by convention to a graphql-ruby class: Mutation.publishPost to Mutations::PublishPost.

class Mutations::PublishPost < GraphQL::Schema::Mutation
  def resolve(id:)
    Post.find(id).tap { |post| post.update!(published: true) }
  end
end

Built for small apps and large ones

Nested mutations, @whereConditions, model validations and Dry::Validation contracts, the @can* family over Pundit, @cache and @cacheControl, Apollo Federation — and, when you need them, a schema cache, persisted queries and an operation allowlist.