How to store metadata on Stripe charges

1require('dotenv').config();
2const express = require('express');
3const stripe = require('stripe')(process.env.STRIPE_SECRET_KEY);
4
5const app = express();
6
7// Create payment with metadata
8app.post('/api/create-payment',
9  express.json(),
10  async (req, res) => {
11    const { amount, currency, orderId, userId, productName } = req.body;
12
13    try {
14      const paymentIntent = await stripe.paymentIntents.create({
15        amount,
16        currency: currency || 'usd',
17        metadata: {
18          order_id: orderId,
19          user_id: userId,
20          product: productName,
21          created_at: new Date().toISOString(),
22        },
23        automatic_payment_methods: { enabled: true },
24      });
25
26      res.json({ clientSecret: paymentIntent.client_secret });
27    } catch (err) {
28      res.status(500).json({ error: err.message });
29    }
30  }
31);
32
33// Webhook reads metadata
34app.post('/webhook',
35  express.raw({ type: 'application/json' }),
36  (req, res) => {
37    const sig = req.headers['stripe-signature'];
38    let event;
39
40    try {
41      event = stripe.webhooks.constructEvent(
42        req.body, sig, process.env.STRIPE_WEBHOOK_SECRET
43      );
44    } catch (err) {
45      return res.status(400).send(`Webhook Error: ${err.message}`);
46    }
47
48    if (event.type === 'payment_intent.succeeded') {
49      const pi = event.data.object;
50      console.log('Payment succeeded:', {
51        stripe_id: pi.id,
52        order_id: pi.metadata.order_id,
53        user_id: pi.metadata.user_id,
54        product: pi.metadata.product,
55        amount: pi.amount / 100,
56        currency: pi.currency,
57      });
58      // TODO: fulfill order, update database
59    }
60
61    res.json({ received: true });
62  }
63);
64
65const PORT = process.env.PORT || 3000;
66app.listen(PORT, () => console.log(`Server on port ${PORT}`));