How do I use JavaScript fetch in Laravel 8?

Question

Issue: So whenever I click the HTML button that activates the Javascript code, I get an error in the console stating: POST http://127.0.0.1:8000/payment 419 (unknown status)

What I have tried

I have tried different ways to get the variable to work, returning it with a view, JSON_ENCODE(), I keep trying to research how to use fetch with Laravel and I feel like I am missing something obvious.

Here is my HTML & Javascript code:

<form action="/payment" method="POST">
@csrf
<button class="btn btn-primary py-3 px-4" id="checkout-button">Proceed to Checkout</button>
<script type="text/javascript">
    // Create an instance of the Stripe object with your publishable API key
    var stripe = Stripe('pk_test_*******************');
    var checkoutButton = document.getElementById('checkout-button');

    checkoutButton.addEventListener('click', function() {
    // Create a new Checkout Session using the server-side endpoint you
    // created in step 3.
        fetch('/payment', {
            method: 'POST', 
            headers: {
               'Content-Type': 'application/json',
               'Accept': 'application/json',
               'url': '/payment',
            },
         })
         .then(function(response) {
             return response.json();
         })
         .then(function(session) {
             return stripe.redirectToCheckout({ sessionId: session.id });
         })
         .then(function(result) {
             // If `redirectToCheckout` fails due to a browser or network
             // error, you should display the localized error message to your
             // customer using `error.message`.
             if (result.error) {
                 alert(result.error.message);
             }
          })
          .catch(function(error) {
              //console.error('Error:', error);
          });
      });
</script>
</form>

This is my route:

Route::post('/payment', [StripePaymentController::class, 'payment']);

This is my controller method:

    /* Sends the stripe key, and payment info to the stripe api, as long as the payment session */
    public function payment() {
        // Sets up the businesses secret key to receive the payment
        \Stripe\Stripe::setApiKey(env('STRIPE_SECRET'));

        // Sets up payment method, and product information
        $session = \Stripe\Checkout\Session::create ([
            'payment_method_types' => ['card'],
            'line_items' => [[
              'price_data' => [
                'currency' => 'usd',
                'product_data' => [
                  'name' => 'T-shirt',
                ],
                'unit_amount' => 2000,
              ],
              'quantity' => 1,
            ]],
            'mode' => 'payment',
            'success_url' => 'http://127.0.0.1:8000/',
            'cancel_url' => 'http://127.0.0.1:8000/cart',
        ]);

        return response()->json(['id' => $session->id]);
    }

Answer 1

It's an error regarding CSRF token mismatch

You will need to manually pass the token in fetch request

fetch('/payment', {
    method: 'POST', 
    headers: {
        'Content-Type': 'application/json',
        'Accept': 'application/json',
        'url': '/payment',
        "X-CSRF-Token": document.querySelector('input[name=_token]').value
    },
})