Publish to an Absinthe GraphQL subscription

README.md

Publish to an Absinthe GraphQL subscription

Use Absinthe.Subscription.publish/3 to manually publish a mutation after a Commanded Ecto projection has updated a read model in the after_update/3 callback function.

example_projector.ex

defmodule MyApp.ExampleProjector do
  use Commanded.Projections.Ecto,
    application: MyApp.Application,
    repo: MyApp.Projections.Repo,
    name: "MyApp.ExampleProjector"

  project %AnEvent{name: name}, fn multi ->
    Ecto.Multi.insert(multi, :example, %ExampleProjection{name: name})
  end

  def after_update(_event, _metadata, %{example: example}) do
    Absinthe.Subscription.publish(MyAppWeb.Endpoint, example, [example: example.id])
  end
end