implement-hotwire

Implement Hotwire

Build modern Rails frontends with Hotwire using progressive enhancement.

Quick Reference

Need	Hotwire choice
Replace part of a page after a link/form	Turbo Frame
Broadcast server-side changes	Turbo Stream
Client-only behavior beyond Turbo	Stimulus controller
Full page navigation	Normal Rails navigation, not a frame

HARD-GATE

ALWAYS start with HTML-only, enhance with Hotwire progressively
NEVER use Turbo Frames for full page navigation
ALWAYS test without JavaScript first

Core Process

1. Build plain HTML — implement the feature with standard Rails forms and links, no Hotwire.
2. Identify update regions — wrap partial-update areas in turbo_frame_tag. Validate: confirm <turbo-frame> appears in the DOM with the correct id.
3. Add Turbo Frames / Streams — scope frame navigation or broadcast via ActionCable. Validate: confirm frame requests return text/vnd.turbo-stream.html in DevTools Network tab; for ActionCable, verify the subscription appears in the Action Cable log.
4. Layer Stimulus — attach controllers only where JavaScript behaviour is needed beyond Turbo. Validate: confirm application.getControllerForElementAndIdentifier(el, 'name') returns the controller instance in the browser console.
5. Verify degraded mode — disable JavaScript in browser DevTools (or run rails test:system with the Capybara :rack_test driver) and confirm all hold without JS: forms submit, links navigate, data persists after reload.

Code Examples

Turbo Frame

<%= turbo_frame_tag "post_#{@post.id}" do %>
  <h1><%= @post.title %></h1>
  <%= link_to "Edit", edit_post_path(@post) %>
<% end %>

Turbo Stream

<%= turbo_stream.append "posts", partial: "post", locals: { post: @post } %>

Stimulus Controller

import { Controller } from "@hotwired/stimulus"

export default class extends Controller {
  static targets = ["name"]
  greet() { alert(`Hello ${this.nameTarget.value}!`) }
}

Register in app/javascript/controllers/index.js:

import GreetController from "./greet_controller"
application.register("greet", GreetController)