This post comes in the sequence of:

• Django Oscar - Payment Gateway Theory - Part 18
• Django Oscar - Payment Gateway (no preview) - Part 19

Content:

1. Stripe Configurations
2. Redirect View
3. Success View

1. Stripe Configurations

pip install stripe

1. Create an account in Stripe
2. Switch to the Test mode
3. From the left bottom click Developers
4. Copy the Publishable Key and the Secret Key as a string to your settings.py
    

STRIPE_PUBLISHABLE_KEY = "*****"   
STRIPE_SECRET_KEY = "*****"       

2. Redirect View

import stripe
from django.conf import settings
from django.urls import reverse

class GatewayRedirect(CheckoutSessionMixin, RedirectView):

    def get_redirect_url(self, **kwargs):

        basket = self.build_submission()['basket']

        if basket.is_empty:
            messages.error(self.request, "Your basket is empty")
            return reverse('basket:summary')

        else: basket.freeze()


        shipping_address = self.get_shipping_address(basket)
        shipping_method = self.get_shipping_method(basket, shipping_address=shipping_address)
        shipping_charge = shipping_method.calculate(basket)

        stripe.api_key = settings.STRIPE_SECRET_KEY
        session = stripe.checkout.Session.create(
            payment_method_types=['card'],
            line_items=[{
                'price_data': {
                    'currency': 'eur',
                    'product_data': {'name': f"Basket #{basket.id}"},
                    'unit_amount': int((basket.total_incl_tax + shipping_charge.incl_tax) * 100),
                },
                'quantity': 1,
            }],
            mode='payment',
            success_url=self.request.build_absolute_uri(reverse('gateway_success', args=[basket.id]) )+"?session_id={CHECKOUT_SESSION_ID}",
            cancel_url=self.request.build_absolute_uri(reverse('gateway_cancel', args=[basket.id]) ),
            metadata={'basket_id': basket.id, 'method': "Stripe"},
        )


        return session.url   

3. Success View

class GatewaySuccess(PaymentDetailsView, OrderPlacementMixin):

    ...
    
    def get(self, request, *args, **kwargs):
        basket_id = kwargs.get('basket_id') 
        basket = Basket.objects.get(id=basket_id, status=Basket.FROZEN)
        if Selector: basket.strategy = Selector().strategy(self.request)
        Applicator().apply(basket, self.request.user, request=self.request)

        
        session_id = request.GET.get("session_id")
        if not session_id:
            messages.error(request, "Session not valid")
            basket.thaw()
            return redirect('basket:summary')

        try:
            session = stripe.checkout.Session.retrieve(session_id)
        except stripe.error.StripeError as e:
            messages.error(request, f"Error verifying the payment: {str(e)}")
            basket.thaw()
            return redirect('basket:summary')

        if session.payment_status != "paid":
            messages.error(request, "Payment not finished")
            basket.thaw()
            return redirect('basket:summary')
    
        
        return self.submit(**self.build_submission(basket=basket))