nullpay-python 0.1.0

NullPay SDK for Python backends

NullPay Python SDK

nullpay-python is the Python equivalent of @nullpay/node.

It follows the same backend-first architecture:

• reads nullpay.json locally for named invoice lookup
• calls the NullPay backend to create and retrieve checkout sessions
• uses the NullPay relayer flow for invoice pre-generation when invoice_hash or salt is missing
• verifies webhook signatures locally with HMAC-SHA256

The smart-contract and Provable SDK work stays on the NullPay backend. This package is a thin Python client for FastAPI, Flask, Django, and plain Python services.

Install

pip install ./packages/nullpay-python

Basic usage

from nullpay import NullPay

client = NullPay({
    "secretKey": "sk_test_...",
    "baseURL": "https://nullpay-backend-ib5q4.ondigitalocean.app/api",
})

session = client.checkout.sessions.create({
    "amount": 10,
    "currency": "USDCX",
    "type": "multipay",
    "success_url": "https://example.com/success",
    "cancel_url": "https://example.com/cancel",
})

print(session["checkout_url"])

API surface

NullPay(config)

Supported config keys:

• secretKey or secret_key
• baseURL or base_url
• projectRoot or project_root
• configPath or config_path
• timeout

load_nullpay_config(project_root=None, config_path=None)

Loads nullpay.json from the provided project root or explicit path.

client.invoices

• get_all()
• get_by_index(i)
• get_by_name(name)
• get_by_type(type_name)

client.checkout.sessions

• create(params)
• retrieve(session_id)

create(...) mirrors the Node SDK behavior:

• accepts nullpay_invoice_name and nullpay_invoice_index
• auto-generates a salt if invoice_hash or salt is missing
• calls /dps/relayer/create-invoice
• polls the Provable salt_to_invoice mapping
• performs best-effort dashboard sync via /invoices
• finally creates the hosted checkout session via /checkout/sessions

client.webhooks

• verify_signature(payload, signature)
• construct_event(payload, signature)

Framework examples

See examples/ for:

• FastAPI
• Flask
• Django

Tests

Run from this package directory:

python -m unittest discover -s tests