Non-Blocking Data Loading for GraphQL

You can pass nonblocking: true to enable a non-blocking dataloader implementation based on Ruby 3’s Fiber.scheduler API:

class MySchema < GraphQL::Schema
  use GraphQL::Dataloader, nonblocking: true # enable parallel data loading
end

Alternatively, you can add a non-blocking GraphQL::Dataloader instance to context[:dataloader]:

context = {
  # ...
  dataloader: GraphQL::Dataloader.new(nonblocking: true),
}
MySchema.execute(query_string, context: context, ...)

Additionally, you must set up a Fiber scheduler with Fiber.set_scheduler before running your query:

Fiber.set_scheduler(MySchedulerImplementation.new)
MySchema.execute(...)

The scheduler must implement Fiber::SchedulerImplementation. Existing implementations can be found at Fiber Scheduler List.

dsh0416/evt supports several backends in Evt::Scheduler.
digital-fabric/libev_scheduler contains Libev::Scheduler, built on libev, an event loop written in C. ⚠️ This works, but it was failing oddly on GitHub actions, so CI is turned off for it.
⚠️ socketry/async contains Async::Scheduler, but I haven’t figured out how to make it work with GraphQL::Dataloader yet. Please update this doc if you know how to!