Challenge 2: Approximate Full-Response Caching — Possible Solution
====================================================================

// app/Http/Controllers/BookController.php

use Illuminate\Support\Facades\Cache;
use App\Models\Book;

public function index()
{
    $books = Cache::remember('books.index.data', 900, function () {
        return Book::with('author')->get();
    });

    return view('books.index', ['books' => $books]);
}

HOW THIS DIFFERS FROM DJANGO'S @cache_page
-----------------------------------------------
This caches only the QUERY RESULT (the Eloquent Collection of books) for
15 minutes — every request within that window still runs the full Blade
template rendering process (view('books.index', [...])) fresh, even
though the underlying data came from the cache instead of the database.
Django's @cache_page decorator, by contrast, caches the ENTIRE FINISHED
HTTP RESPONSE — meaning a cached request skips template rendering
entirely and returns the exact same bytes that were computed the first
time, making it a strictly cheaper operation per request than this
Laravel approach, which still pays the Blade-rendering cost every time
even on a "cache hit" for the data.

WHY THIS WORKS AS AN APPROXIMATION
--------------------------------------
- The expensive part — the database query (and any N+1-prone relationship
  loading via with('author')) — is exactly what gets skipped on repeated
  requests, which is usually where the real cost lives for a
  database-backed page.
- Achieving Django's TRUE response-level caching in Laravel would
  require either a dedicated package (like spatie/laravel-responsecache,
  which wraps the whole response object, not just data) or manually
  caching the fully-rendered HTML string itself (e.g.
  Cache::remember('books.index.html', 900, fn() =>
  view('books.index', [...])->render())) — the latter approximates
  Django's behavior more closely, at the cost of losing per-request
  dynamic content (like a CSRF token or a personalized greeting) unless
  handled carefully, exactly the same trade-off Django's template
  fragment caching chapter warned about for content that must stay fresh
  per-request.