Integrating 4Geeks Payments API into a Node.js Application¶

mkdir my-payment-app && cd my-payment-app
npm init -y
npm install express axios dotenv cors

my-payment-app/
├── .env
├── server.js
├── routes/
│   └── payments.js
└── package.json

FOURGEEKS_PAYMENTS_SECRET_KEY=sk_test_your_secret_key_here
FOURGEEKS_PAYMENTS_PUBLIC_KEY=pk_test_your_public_key_here
FOURGEEKS_PAYMENTS_API_URL=https://api.4geeks.io/v1
PORT=3000

require('dotenv').config();
const express = require('express');
const cors = require('cors');
const paymentRoutes = require('./routes/payments');

const app = express();

app.use(cors());
app.use(express.json());
app.use('/api/payments', paymentRoutes);

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});

const express = require('express');
const axios = require('axios');
const router = express.Router();

const API_URL = process.env.FOURGEEKS_PAYMENTS_API_URL;
const SECRET_KEY = process.env.FOURGEEKS_PAYMENTS_SECRET_KEY;

const api = axios.create({
  baseURL: API_URL,
  headers: {
    'Authorization': `Bearer ${SECRET_KEY}`,
    'Content-Type': 'application/json',
  },
});

// Create a one-time charge
router.post('/charges', async (req, res) => {
  try {
    const { amount, currency, customer_id, description } = req.body;

    const response = await api.post('/charges', {
      amount,           // Amount in cents (e.g., 1000 = $10.00)
      currency,         // e.g., 'USD', 'EUR', 'CRC'
      customer_id,      // Existing customer ID or create new
      description,
      capture: true,    // Auto-capture the charge
    });

    res.json({ success: true, charge: response.data });
  } catch (error) {
    console.error('Charge error:', error.response?.data || error.message);
    res.status(error.response?.status || 500).json({
      success: false,
      error: error.response?.data || 'Failed to create charge',
    });
  }
});

// Create a customer
router.post('/customers', async (req, res) => {
  try {
    const { email, name, phone, metadata } = req.body;

    const response = await api.post('/customers', {
      email,
      name,
      phone,
      metadata, // Optional: custom key-value pairs
    });

    res.json({ success: true, customer: response.data });
  } catch (error) {
    res.status(error.response?.status || 500).json({
      success: false,
      error: error.response?.data || 'Failed to create customer',
    });
  }
});

// Generate a payment link
router.post('/payment-links', async (req, res) => {
  try {
    const { amount, currency, description, customer_email, success_url, cancel_url } = req.body;

    const response = await api.post('/payment-links', {
      amount,
      currency,
      description,
      customer_email,
      success_url,    // Redirect after successful payment
      cancel_url,     // Redirect if customer cancels
    });

    res.json({ success: true, payment_link: response.data });
  } catch (error) {
    res.status(error.response?.status || 500).json({
      success: false,
      error: error.response?.data || 'Failed to create payment link',
    });
  }
});

// Process a refund
router.post('/charges/:charge_id/refund', async (req, res) => {
  try {
    const { charge_id } = req.params;
    const { amount, reason } = req.body;

    const response = await api.post(`/charges/${charge_id}/refunds`, {
      amount,  // Optional: partial refund (in cents). Omit for full refund
      reason,  // e.g., 'duplicate', 'fraudulent', 'requested_by_customer'
    });

    res.json({ success: true, refund: response.data });
  } catch (error) {
    res.status(error.response?.status || 500).json({
      success: false,
      error: error.response?.data || 'Failed to process refund',
    });
  }
});

// Get charge details
router.get('/charges/:charge_id', async (req, res) => {
  try {
    const { charge_id } = req.params;
    const response = await api.get(`/charges/${charge_id}`);
    res.json({ success: true, charge: response.data });
  } catch (error) {
    res.status(error.response?.status || 500).json({
      success: false,
      error: error.response?.data || 'Failed to get charge',
    });
  }
});

module.exports = router;

// Webhook endpoint
app.post('/webhooks/payments', express.raw({ type: 'application/json' }), (req, res) => {
  const signature = req.headers['x-4geeks-signature'];
  const payload = req.body;

  // Verify webhook signature (implement verification logic)
  // const isValid = verifyWebhookSignature(payload, signature);
  // if (!isValid) return res.status(401).send('Invalid signature');

  const event = JSON.parse(payload);

  switch (event.type) {
    case 'charge.succeeded':
      console.log('Payment successful:', event.data.charge_id);
      // Update order status, send confirmation email, etc.
      break;
    case 'charge.failed':
      console.log('Payment failed:', event.data.charge_id);
      // Notify customer, retry logic, etc.
      break;
    case 'refund.completed':
      console.log('Refund processed:', event.data.refund_id);
      // Update order status, notify customer, etc.
      break;
    case 'subscription.created':
      console.log('New subscription:', event.data.subscription_id);
      // Activate subscription, send welcome email, etc.
      break;
    default:
      console.log('Unhandled event type:', event.type);
  }

  res.json({ received: true });
});

node server.js

# Create a customer
curl -X POST http://localhost:3000/api/payments/customers \
  -H "Content-Type: application/json" \
  -d '{"email": "test@example.com", "name": "John Doe"}'

# Create a charge
curl -X POST http://localhost:3000/api/payments/charges \
  -H "Content-Type: application/json" \
  -d '{"amount": 1000, "currency": "USD", "customer_id": "cus_xxx", "description": "Test charge"}'

# Generate a payment link
curl -X POST http://localhost:3000/api/payments/payment-links \
  -H "Content-Type: application/json" \
  -d '{"amount": 2500, "currency": "USD", "description": "Premium Plan", "success_url": "https://yoursite.com/success", "cancel_url": "https://yoursite.com/cancel"}'