ruby 32 lines · 6 steps

How Turbo Stream toasts broadcast in Rails

A service object pushes flash toast messages to a user's browser over Turbo Streams without a full page reload.

Explained by highlit

Rails Intermediate turbo-streams service-object real-time broadcasting websockets

1class ToastBroadcaster
include ActionView::RecordIdentifier
3 
def self.broadcast_to(user, message:, type: :notice)
  new(user).broadcast(message: message, type: type)
end
7 
def initialize(user)
  @user = user
end
11 
def broadcast(message:, type:)
  Turbo::StreamsChannel.broadcast_prepend_to(
    @user,
    target: "toasts",
    partial: "shared/toast",
    locals: { toast_id: SecureRandom.uuid, message: message, type: type }
  )
end
20end
21 
22class FlashToastsController < ApplicationController
def create
  ToastBroadcaster.broadcast_to(
    current_user,
    message: params.require(:message),
    type: params.fetch(:type, :notice)
  )
29 
  head :no_content
end
32end

01 / 01

STEP 01

Walkthrough

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Three takeaways

1A small service object keeps broadcasting logic out of the controller and reusable across the app.
2Turbo Stream broadcasts target a DOM id and render a partial, letting the server drive UI updates over a WebSocket.
3Streaming per-user means passing the user as the stream identifier so only that person's browser receives the update.

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