How do I know which user has made the payment in stripe - node.js

Question

I am integrating stripe with my application. I want to receive a one time payment from a logged in user and once the payment is done maybe save the payment status in the database.
I have set up the stripe-checkout and stripe-webhook. But how would i know which logged in user from the client side has made the payment so that i can set the payment status for that user in the database.
Here is how my checkout and webhook look like.
app.post("/checkout-session", async (req, res) => {
try {
const session = await stripe.checkout.sessions.create({
payment_method_types: ["card"],
mode: "payment",
line_items: req.body.items.map((item) => {
const storeItem = storeItems.get(item.id);
return {
price_data: {
currency: "usd",
product_data: {
name: storeItem.name,
},
unit_amount: storeItem.priceInCents,
},
quantity: item.quantity,
};
}),
success_url: `${process.env.CLIENT_URL}/success`,
cancel_url: `${process.env.CLIENT_URL}/failure`,
});
res.json({ url: session.url });
} catch (e) {
res.status(500).json({ error: e.message });
}
});
app.post("/webhook", express.raw({ type: "application/json" }), (req, res) => {
let event;
// Only verify the event if you have an endpoint secret defined.
// Otherwise use the basic event deserialized with JSON.parse
if (process.env.STRIPE_WEBHOOK_SECRET) {
// Get the signature sent by Stripe
const signature = req.headers["stripe-signature"];
try {
event = stripe.webhooks.constructEvent(
req.body,
signature,
process.env.STRIPE_WEBHOOK_SECRET
);
} catch (err) {
console.log(`⚠️ Webhook signature verification failed.`, err.message);
return res.sendStatus(400);
}
}
// Handle the event
switch (event.type) {
case "payment_intent.succeeded":
const paymentIntent = event.data.object;
console.log(`PaymentIntent for ${paymentIntent.amount} was successful!`);
console.log(paymentIntent);
// Then define and call a methstripe loginod to handle the successful payment intent.
// handlePaymentIntentSucceeded(paymentIntent);
break;
case "payment_method.attached":
const paymentMethod = event.data.object;
// Then define and call a method to handle the successful attachment of a PaymentMethod.
// handlePaymentMethodAttached(paymentMethod);
break;
case "payment_intent.payment_failed":
const failedpaymentIntent = event.data.object;
console.log(`PaymentIntent for ${paymentIntent.amount} failed!`);
// Then define and call a methstripe loginod to handle the successful payment intent.
// handlePaymentIntentSucceeded(paymentIntent);
break;
case "checkout.session.completed":
console.log(event.data.object);
// console.log(`PaymentIntent for ${paymentIntent.amount} failed!`);
// Then define and call a methstripe loginod to handle the successful payment intent.
// handlePaymentIntentSucceeded(paymentIntent);
break;
default:
// Unexpected event type
console.log(`Unhandled event type ${event.type}.`);
}
// Return a 200 response to acknowledge receipt of the event
res.send();
});```

Answer 1

In checkout.session.completed event, you will be able to find customer_details.email in the Checkout Session object to identify the customer.
Alternatively, your internal customer ID might be set under metadata parameter in Checkout Session Creation API. Metadata will be present in checkout.session.completed after successful payment which you can use to update the payment status in your database.

Answer 2

At the login time, you can use json web token (jwt) to send logged in user object in encrypted format and use local storage to store that token. and with request, send this token to backend and decode it. You will get user object from that and then you can able to find which user is sending request.
https://www.npmjs.com/package/jsonwebtoken