turbo_permanent_cable_helper.rb

# frozen_string_literal: true
module TurboPermanentCableHelper
  def turbo_permanent_stream_from(*streamables, **attributes)
    raise ArgumentError, "streamables can't be blank" unless streamables.any?(&:present?)
    raise ArgumentError, "an id is required" if attributes[:id].blank?

    attributes[:channel] = attributes[:channel]&.to_s || "Turbo::StreamsChannel"
    attributes[:'signed-stream-name'] = Turbo::StreamsChannel.signed_stream_name(streamables)
    attributes[:data] ||= {}
    attributes[:data][:turbo_permanent] = true

    tag.turbo_permanent_cable_stream_source(**attributes)
  end
end

turbo_permanent_cable_stream_source_element.js

await customElements.whenDefined("turbo-cable-stream-source");
// https://github.com/hotwired/turbo-rails/blob/30cd8fcc6f82c1ad4edd1ed6069ba878f21f02b3/app/javascript/turbo/cable_stream_source_element.js
const TurboCableStreamSourceElement = customElements.get("turbo-cable-stream-source");

class TurboPermanentCableStreamSourceElement extends TurboCableStreamSourceElement {
  static get observedAttributes() { return TurboCableStreamSourceElement.observedAttributes || []; }

  async connectedCallback() {
    if (this.disconnecting) {
      this.disconnecting = false;
      return;
    }

    return super.connectedCallback();
  }

  async disconnectedCallback() {
    // delay the disconnect to allow a potential re-connect to occur
    // and avoid performing disconnect+reconnect behavior unnecessarily
    this.disconnecting = true;
    await new Promise(requestAnimationFrame);
    if (!this.disconnecting) return;

    return super.disconnectedCallback();
  }
}

if (!customElements.get("turbo-permanent-cable-stream-source")) {
  customElements.define("turbo-permanent-cable-stream-source", TurboPermanentCableStreamSourceElement);
}