Use session to store visitor shopping carts, and the database stores logged in to user shopping carts for persistence; 2. Create cart tables to store user shopping cart data; 3. Create CartService service class to encapsulate addition, deletion, modification and search logic; 4. Create CartController controller to handle shopping cart operations; 5. Define routes in web.php; 6. Create Blade template to display shopping cart content; 7. Merge session shopping carts to the database when the user logs in. This solution implements a hybrid shopping cart system that supports visitors and certified users, and is durable, scalable and meets practical application needs.

Implementing a shopping cart in Laravel can be done in several ways depending on your needs—session-based for guest users, database-backed for persistent carts, or using a package like gloudemans/shoppingcart (now archived, but still used). Below is a practical guide to building a simple yet effective cart system from scratch.

1. Decide on Cart Storage: Session vs Database

For most Laravel apps, you'll want to support both guests and logged-in users :

• Guests : Store cart in the session.
• Logged-in users : Store cart in the database, synchronized with session for consistency.

This hybrid approach gives flexibility and persistence.

2. Database Setup (for Authenticated Users)

If you want persistent carts, create a cart table:

 php artisan make:migration create_cart_table

 Schema::create('cart', function (Blueprint $table) {
    $table->id();
    $table->foreignId('user_id')->constrained()->onDelete('cascade');
    $table->foreignId('product_id')->constrained();
    $table->integer('quantity')->default(1);
    $table->timestamps();
});

Run migration:

 php artisan migrate

3. Create a Cart Service Class

Instead of putting logic in controllers, create a reusable service:

 php artisan make:service CartService

In app/Services/CartService.php :

 namespace App\Services;

use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Session;
use App\Models\Cart;
use App\Models\Product;

class CartService
{
    public function get()
    {
        if (Auth::check()) {
            return Cart::with('product')->where('user_id', Auth::id())->get();
        }

        return Session::get('cart', []);
    }

    public function add($productId, $quantity = 1)
    {
        $product = Product::findOrFail($productId);

        if (Auth::check()) {
            $cartItem = Cart::firstOrNew([
                'user_id' => Auth::id(),
                'product_id' => $product->id,
            ]);

            $cartItem->quantity = $quantity;
            $cartItem->save();
        } else {
            $cart = Session::get('cart', []);
            if (isset($cart[$productId])) {
                $cart[$productId]['quantity'] = $quantity;
            } else {
                $cart[$productId] = [
                    'product_id' => $product->id,
                    'name' => $product->name,
                    'price' => $product->price,
                    'quantity' => $quantity,
                ];
            }
            Session::put('cart', $cart);
        }
    }

    public function update($productId, $quantity)
    {
        if (Auth::check()) {
            $cartItem = Cart::where('user_id', Auth::id())
                           ->where('product_id', $productId)
                           ->first();
            if ($cartItem) {
                if ($quantity <= 0) {
                    $cartItem->delete();
                } else {
                    $cartItem->quantity = $quantity;
                    $cartItem->save();
                }
            }
        } else {
            $cart = Session::get(&#39;cart&#39;, []);
            if (isset($cart[$productId])) {
                if ($quantity <= 0) {
                    unset($cart[$productId]);
                } else {
                    $cart[$productId][&#39;quantity&#39;] = $quantity;
                }
                Session::put(&#39;cart&#39;, $cart);
            }
        }
    }

    public function remove($productId)
    {
        $this->update($productId, 0);
    }

    public function clear()
    {
        if (Auth::check()) {
            Cart::where(&#39;user_id&#39;, Auth::id())->delete();
        } else {
            Session::forget(&#39;cart&#39;);
        }
    }

    public function total()
    {
        $cart = $this->get();
        if (Auth::check()) {
            return $cart->sum(fn($item) => $item->product->price * $item->quantity);
        } else {
            return collect($cart)->sum(fn($item) => $item[&#39;price&#39;] * $item[&#39;quantity&#39;]);
        }
    }
}

Make sure your Product model is set up and has a price field.

4. Create Cart Controller

 php artisan make:controller CartController

 namespace App\Http\Controllers;

use App\Services\CartService;
use Illuminate\Http\Request;

class CartController extends Controller
{
    protected $cartService;

    public function __construct(CartService $cartService)
    {
        $this->cartService = $cartService;
    }

    public function index()
    {
        $cartItems = $this->cartService->get();
        $total = $this->cartService->total();

        return view('cart.index', compact('cartItems', 'total'));
    }

    public function add(Request $request)
    {
        $this->cartService->add($request->id, $request->quantity ?? 1);

        return redirect()->back()->with('success', 'Item added to cart!');
    }

    public function update(Request $request, $id)
    {
        $this->cartService->update($id, $request->quantity);

        return redirect()->route('cart.index');
    }

    public function remove($id)
    {
        $this->cartService->remove($id);

        return redirect()->route('cart.index');
    }

    public function clear()
    {
        $this->cartService->clear();

        return redirect()->route('cart.index');
    }
}

5. Define Routes

In routes/web.php :

 use App\Http\Controllers\CartController;

Route::middleware(['auth'])->group(function () {
    Route::get('/cart', [CartController::class, 'index'])->name('cart.index');
    Route::post('/cart/add/{id}', [CartController::class, 'add'])->name('cart.add');
    Route::put('/cart/update/{id}', [CartController::class, 'update'])->name('cart.update');
    Route::delete('/cart/remove/{id}', [CartController::class, 'remove'])->name('cart.remove');
    Route::delete('/cart/clear', [CartController::class, 'clear'])->name('cart.clear');
});

You can allow add without auth if you want guests to add items.

6. Blade Template Example

resources/views/cart/index.blade.php :

 <h1>Your Cart</h1>

@if(session(&#39;success&#39;))
    <div class="alert alert-success">{{ session(&#39;success&#39;) }}</div>
@endif

<ul>
    @foreach($cartItems as $item)
        <li>
            {{ $item[&#39;name&#39;] ?? $item->product->name }}
            x {{ $item[&#39;quantity&#39;] ?? $item->quantity }}
            = ${{ ($item[&#39;price&#39;] ?? $item->product->price) * ($item[&#39;quantity&#39;] ?? $item->quantity) }}

            <form method="POST" action="{{ route(&#39;cart.update&#39;, $item[&#39;product_id&#39;] ?? $item->product_id) }}" style="display:inline;">
                @csrf
                @method(&#39;PUT&#39;)
                <input type="number" name="quantity" value="{{ $item[&#39;quantity&#39;] ?? $item->quantity }}" min="1" />
                <button type="submit">Update</button>
            </form>

            <form method="POST" action="{{ route(&#39;cart.remove&#39;, $item[&#39;product_id&#39;] ?? $item->product_id) }}" style="display:inline;">
                @csrf
                @method(&#39;DELETE&#39;)
                <button type="submit">Remove</button>
            </form>
        </li>
    @endforeach
</ul>

<p><strong>Total: ${{ number_format($total, 2) }}</strong></p>
<a href="{{ route(&#39;checkout&#39;) }}">Proceed to Checkout</a>

7. Sync Cart on Login (Optional but Recommended)

When a user logs in, merge session cart into the database.

In your LoginController or use an event listener:

 // In Authenticated method of LoginController or use event
public function authenticated(Request $request, $user)
{
    // Merge session cart into database
    $sessionCart = Session::get('cart', []);
    foreach ($sessionCart as $item) {
        $cartItem = Cart::firstOrNew([
            'user_id' => $user->id,
            'product_id' => $item['product_id'],
        ]);
        $cartItem->quantity = $item['quantity'];
        $cartItem->save();
    }

    Session::forget('cart'); // Clear session cart
}

Final Notes

• You can enhance this with AJAX for smoother UX.
• Consider using Laravel Livewire for real-time cart updates.
• For large-scale apps, consider using Redis or a dedicated cart microservice.

Basically, you now have a flexible cart system that works for both guests and logged-in users, persists data, and is easy to extend. Not overly complex, but covers real-world needs.

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