Reproduction for hotwired/turbo-rails#697

Author: sfnelson

app/controllers/pages_controller.rb

@@ -0,0 +1,18 @@
+class PagesController < ApplicationController
+  before_action :set_page, only: %i[ show ]
+
+  # GET /pages or /pages.json
+  def index
+    @pages = Page.all
+  end
+
+  # GET /pages/1 or /pages/1.json
+  def show
+  end
+
+  private
+
+  def set_page
+    @page = Page.find_by(slug: params[:slug])
+  end
+end

app/javascript/controllers/meta_controller.js

@@ -0,0 +1,28 @@
+import { Controller } from "@hotwired/stimulus"
+
+export default class extends Controller {
+  initialize() {
+    super.initialize()
+
+    this.observer = new MutationObserver(this.onChange);
+  }
+
+  connect() {
+    this.observer.observe(document.head, { childList: true })
+    this.element.textContent = this.metaTagsContent;
+  }
+
+  disconnect() {
+    delete this.observer;
+  }
+
+  onChange = () => {
+    this.element.textContent = this.metaTagsContent;
+  }
+
+  get metaTagsContent() {
+    return Array.from(document.head.querySelectorAll("meta")).reduce(
+      (result, el) => result + "\n" + el.outerHTML,
+      "")
+  }
+}

app/models/page.rb

@@ -0,0 +1,2 @@
+class Page < ApplicationRecord
+end

app/views/pages/index.html.erb

@@ -0,0 +1,21 @@
+<% content_for :title, "Pages" %>
+
+<article>
+  <h1>Current Page</h1>
+  <turbo-frame id="page" data-turbo-action="advance"></turbo-frame>
+</article>
+
+<nav>
+  <h2>Navigation</h2>
+  <ul>
+    <% @pages.each do |page| %>
+      <li><%= link_to page.title, page_path(page.slug), data: { turbo_frame: "page" } %></li>
+    <% end %>
+  </ul>
+</nav>
+
+<article>
+  <h2>Meta content</h2>
+  <pre data-controller="meta">
+  </pre>
+</article>

app/views/pages/show.html.erb

@@ -0,0 +1,13 @@
+<% content_for :title, @page.title %>
+<% content_for(:head) do %>
+  <%= stylesheet_link_tag :app, "data-turbo-track": "reload" %>
+  <%= javascript_importmap_tags %>
+<% end %>
+
+<%= link_to("Home", root_path) %>
+
+<div>
+  <%= turbo_frame_tag("page") do %>
+    <%= @page.body %>
+  <% end %>
+</div>

config/routes.rb

@@ -9,6 +9,8 @@
   # get "manifest" => "rails/pwa#manifest", as: :pwa_manifest
   # get "service-worker" => "rails/pwa#service_worker", as: :pwa_service_worker
 
+  resources :pages, param: :slug
+
   # Defines the root path route ("/")
-  # root "posts#index"
+  root "pages#index"
 end

db/migrate/20250305224131_create_pages.rb

@@ -0,0 +1,11 @@
+class CreatePages < ActiveRecord::Migration[8.0]
+  def change
+    create_table :pages do |t|
+      t.string :slug
+      t.string :title
+      t.string :body
+
+      t.timestamps
+    end
+  end
+end

db/schema.rb

@@ -1,9 +1,9 @@
 # This file should ensure the existence of records required to run the application in every environment (production,
 # development, test). The code here should be idempotent so that it can be executed at any point in every environment.
 # The data can then be loaded with the bin/rails db:seed command (or created alongside the database with db:setup).
-#
-# Example:
-#
-#   ["Action", "Comedy", "Drama", "Horror"].each do |genre_name|
-#     MovieGenre.find_or_create_by!(name: genre_name)
-#   end
+
+["Action", "Comedy", "Drama", "Horror"].each do |genre_name|
+  Page.find_or_create_by!(slug: genre_name.parameterize) do |page|
+    page.update(title: genre_name, body: genre_name)
+  end
+end