Stripe processed, now what?

Question

I'm trying to build a serverless NuxtJS app, utilizing firebase for authentication, netlify for deployment (and functions) and stripe for payment.

This whole payment-process and serverless functions on netlify is all new to me, so this might be a nooby question.

I've followed serveral docs and guides, and accomplished an app with firebase authentication, netlify deployment and serverless functions making me able to process a stripe payment - now I just cant figure out the next step. My stripe success_url leads to a /pages/succes/index.js route containing a success message -> though here I'd need some data response from Stripe, making me able to present the purchased item and also attaching the product id as a "bought-product" entry on the user object in firebase (the products will essentially be an upgrade to the user profile).

Click "buy product" function

async buyProduct(sku, qty) {
  const data = {
    sku: sku,
    quantity: qty,
  };

  const response = await fetch('/.netlify/functions/create-checkout', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
    },
    body: JSON.stringify(data),
  }).then((res) => res.json());

  console.log(response);

  const stripe = await loadStripe(response.publishableKey);
  const { error } = await stripe.redirectToCheckout({
    sessionId: response.sessionId,
  });

  if (error) {
    console.error(error);
  }
}

create-checkout Netlify function

const stripe = require('stripe')(process.env.STRIPE_SECRET_KEY);
const inventory = require('./data/products.json');

exports.handler = async (event) => {
  const { sku, quantity } = JSON.parse(event.body);
  const product = inventory.find((p) => p.sku === sku);
  const validatedQuantity = quantity > 0 && quantity < 11 ? quantity : 1;

  const session = await stripe.checkout.sessions.create({
    payment_method_types: ['card'],
    billing_address_collection: 'auto',
    shipping_address_collection: {
      allowed_countries: ['US', 'CA'],
    },
    success_url: `${process.env.URL}/success`,
    cancel_url: process.env.URL,
    line_items: [
      {
        name: product.name,
        description: product.description,
        images: [product.image],
        amount: product.amount,
        currency: product.currency,
        quantity: validatedQuantity,
      },
    ],
  });

  return {
    statusCode: 200,
    body: JSON.stringify({
      sessionId: session.id,
      publishableKey: process.env.STRIPE_PUBLISHABLE_KEY,
    }),
  };
};

Please let me know if you need more information, or something doesnt make sense!

tldr; I've processed a Stripe payment in a serverless app using Netlify function, and would like on the success-page to be able to access the bought item and user information.

Answer 1

When you create your Checkout Session and define your success_url, you can append session_id={CHECKOUT_SESSION_ID} as a template where Stripe will auto-fill in the session ID. See https://stripe.com/docs/payments/checkout/accept-a-payment#create-checkout-session

In your case you'd do:

success_url: `${process.env.URL}/success?session_id={CHECKOUT_SESION_ID}`,

Then when your user is redirected to your success URL you can retrieve the session with the session ID and do any purchase fulfilment.