Python

pip install nopayn-sdk

from nopayn import NoPaynClient

client = NoPaynClient(
    api_key="your-api-key",
    merchant_id="your-project",
)

result = client.generate_payment_url(
    amount=1295,             # €12.95 in cents
    currency="EUR",
    merchant_order_id="ORDER-001",
    description="Premium Widget",
    return_url="https://shop.example.com/success",
    failure_url="https://shop.example.com/failure",
    webhook_url="https://shop.example.com/webhook",
    locale="en-GB",
    expiration_period="PT30M",
)

# Redirect the customer
# result.order_url   → HPP (customer picks payment method)
# result.payment_url → direct link to the first transaction's payment method
# result.signature   → HMAC-SHA256 for verification
# result.order_id    → NoPayn order UUID

@app.route("/webhook", methods=["POST"])
def webhook():
    verified = client.verify_webhook(request.get_data(as_text=True))

    print(verified.order.status)  # 'completed', 'cancelled', etc.
    print(verified.is_final)      # True when the order won't change

    if verified.order.status == "completed":
        # Fulfil the order
        pass

    return "", 200

PaymentUrlResult(
    order_id="...",       # NoPayn order UUID
    order_url="...",      # HPP URL
    payment_url="...",    # Direct payment URL (first transaction)
    signature="...",      # HMAC-SHA256 of amount:currency:order_id
    order=Order(...),     # Full order object
)

from nopayn import generate_signature, verify_signature

sig = generate_signature("your-api-key", 1295, "EUR", "order-uuid")
ok = verify_signature("your-api-key", 1295, "EUR", "order-uuid", sig)

from nopayn import ApiError, NoPaynError, WebhookError

try:
    client.create_order(amount=100, currency="EUR")
except ApiError as exc:
    print(exc.status_code)  # 401, 400, etc.
    print(exc.error_body)   # Raw API error response
except NoPaynError as exc:
    print(exc)              # Network or parsing error