python-getpaid-paynow 0.1.0

Paynow payment gateway integration for python-getpaid ecosystem.

getpaid-paynow

Paynow payment gateway plugin for the python-getpaid ecosystem. Provides an async HTTP client (PaynowClient) and a payment processor (PaynowProcessor) that integrates with getpaid-core's BaseProcessor interface. Authentication uses API Key + HMAC-SHA256 signature against the Paynow V3 REST API.

Architecture

The plugin is split into two layers:

• PaynowClient -- low-level async HTTP client wrapping the Paynow V3 REST API. Uses httpx.AsyncClient with API Key authentication and HMAC-SHA256 request signing. Can be used standalone or as an async context manager for connection reuse.
• PaynowProcessor -- high-level payment processor implementing BaseProcessor. Orchestrates payment creation, callback/notification handling, status polling, and refunds. Integrates with the getpaid-core FSM for state transitions.

Key Features

• Create payment -- register a payment and get a redirect URL
• Notification handling -- verify HMAC signature and process status changes
• Status polling -- fetch current payment status via API
• Refund -- create, check, and cancel refunds
• Payment methods -- retrieve available payment methods
• HMAC-SHA256 signatures -- automatic request and notification signing
• PUSH and PULL -- notification-based flow with optional status polling

Quick Usage

Standalone Client

import asyncio
from decimal import Decimal
from getpaid_paynow import PaynowClient

async def main():
    async with PaynowClient(
        api_key="your-api-key",
        signature_key="your-signature-key",
        api_url="https://api.sandbox.paynow.pl",
    ) as client:
        # Create a payment
        response = await client.create_payment(
            amount=Decimal("49.99"),
            currency="PLN",
            external_id="order-001",
            description="Order #001",
            buyer_email="[e-mail]",
            continue_url="https://shop.example.com/return/order-001",
        )
        redirect_url = response["redirectUrl"]
        print(f"Redirect buyer to: {redirect_url}")

asyncio.run(main())

With django-getpaid

Register the plugin via entry point in pyproject.toml:

[project.entry-points."getpaid.backends"]
paynow = "getpaid_paynow.processor:PaynowProcessor"

Then configure in your Django settings (or config dict):

GETPAID_BACKEND_SETTINGS = {
    "paynow": {
        "api_key": "your-api-key",
        "signature_key": "your-signature-key",
        "sandbox": True,
        "notification_url": "https://shop.example.com/payments/{payment_id}/callback/",
        "continue_url": "https://shop.example.com/payments/{payment_id}/return/",
    }
}

Configuration Reference

Key	Type	Default	Description
api_key	str	required	API key from Paynow merchant panel
signature_key	str	required	Signature key for HMAC calculation
sandbox	bool	True	Use sandbox or production API
notification_url	str	""	Notification URL template; use {payment_id} placeholder
continue_url	str	""	Return URL template; use {payment_id} placeholder

Supported Currencies

PLN, EUR, USD, GBP (4 total).

Limitations

Paynow does not support pre-authorization. The charge() and release_lock() methods raise NotImplementedError.

Requirements

• Python 3.12+
• python-getpaid-core >= 0.1.0
• httpx >= 0.27.0

Related Projects

• python-getpaid-core -- core abstractions (protocols, FSM, processor base class)
• django-getpaid -- Django adapter (models, views, admin)

License

MIT

Disclaimer

This project has nothing in common with the getpaid plone project. It is part of the django-getpaid / python-getpaid ecosystem.

Credits

Created by Dominik Kozaczko.