Class: AgUi::EventBridge

Inherits:

Object

• Object
• AgUi::EventBridge

Defined in:

lib/ag_ui/event_bridge.rb

Overview

The seam between brute's turn pipeline and the AG-UI SSE stream.

Brute middleware and terminal procs emit AG-UI events through the env; a bridge subscribes to that vocabulary on the agent's hooks and translates each one into the matching typed SSE emitter as it arrives — the browser sees deltas mid-turn, not after.

agent = Brute.agent.use(...).run(terminal)
AgUi::EventBridge.new(stream).subscribe(agent)
agent.start(messages)

Brute's own lifecycle events (:llm_start, :tool_end, the middleware and trace sets) are simply never subscribed to here, so only the AG-UI vocabulary reaches the wire.

Constant Summary

TRANSLATIONS =

{
  text_message_start:        :translate_text_start,
  text_message_content:      :translate_text_content,
  text_message_end:          :translate_text_end,
  tool_call_start:           :translate_tool_call_start,
  tool_call_args:            :translate_tool_call_args,
  tool_call_end:             :translate_tool_call_end,
  tool_call_result:          :translate_tool_call_result,
  state_snapshot:            :translate_state_snapshot,
  state_delta:               :translate_state_delta,
  messages_snapshot:         :translate_messages_snapshot,
  activity_snapshot:         :translate_activity_snapshot,
  reasoning_start:           :translate_reasoning_start,
  reasoning_message_start:   :translate_reasoning_message_start,
  reasoning_message_content: :translate_reasoning_message_content,
  reasoning_message_end:     :translate_reasoning_message_end,
  reasoning_end:             :translate_reasoning_end,
  step_started:              :translate_step_started,
  step_finished:             :translate_step_finished,
  custom:                    :translate_custom,
  raw:                       :translate_raw,
}.freeze

Instance Method Summary

• #initialize(stream) ⇒ EventBridge constructor

  A new instance of EventBridge.

• #subscribe(hooks) ⇒ Object

  Registers the whole vocabulary above on a hooks registry — or on anything else answering on, which a Brute pipeline builder does.

Constructor Details

#initialize(stream) ⇒ EventBridge

Returns a new instance of EventBridge.

# File 'lib/ag_ui/event_bridge.rb', line 45

def initialize(stream)
  @stream = stream
end

Instance Method Details

#subscribe(hooks) ⇒ Object

Registers the whole vocabulary above on a hooks registry — or on anything else answering on, which a Brute pipeline builder does. Answers what it was given, so it composes in one line.

Every subscriber takes (env, data, trace): brute hands the env first and appends the trace last, and a translation wants neither — the data is the whole of an AG-UI event.

# File 'lib/ag_ui/event_bridge.rb', line 56

def subscribe(hooks)
  TRANSLATIONS.each do |event, handler|
    hooks.on(event) { |_env, data, _trace| send(handler, data || {}) }
  end
  hooks
end