payment-infra 1.0.5

Reusable Django payment infrastructure with idempotency and webhook support

payment_infra

A reusable Django package for payment orchestration with clean architecture, idempotency, provider abstraction, and webhook handling.

Features

• Provider abstraction (paystack, stripe, monnify) through a shared interface.
• Idempotent payment initialization flow to avoid duplicate charges.
• Service-layer orchestration (PaymentService, WebhookService) for testable business logic.
• Django REST API endpoints for charge, verify, and webhook processing.
• Extensible architecture for adding new providers without changing API/service boundaries.

---

Package Architecture

payment_infra/
├── api/                        # DRF serializers, views, and URL routes
├── application/                # Use-cases/services + provider/repository interfaces
├── domain/                     # Core entities and domain models
├── infrastructure/
│   ├── idempotency/            # Idempotency persistence and locking
│   ├── providers/              # Gateway adapters (Paystack/Stripe/Monnify)
│   ├── repositories/           # Data access adapters
│   └── tasks/                  # Async task hooks (Celery)
└── migrations/                 # Django migrations

---

Installation

From package index

pip install payment_infra

For local development

git clone https://github.com/0FFSIDE1/payment_infra.git
cd payment_infra
python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt

---

Quick Start in a Django Project

1) Add apps

INSTALLED_APPS = [
    # ...
    "rest_framework",
    "payment_infra",
]

2) Include URLs

from django.urls import include, path

urlpatterns = [
    # ...
    path("payments/", include("payment_infra.api.urls")),
]

3) Configure provider settings

Set DJANGO_PAYMENTS_PROVIDER to one of:

• paystack
• stripe
• monnify

Provider-specific settings:

Paystack

• PAYSTACK_SECRET_KEY
• PAYSTACK_PUBLIC_KEY
• PAYSTACK_BASE_URL (optional)
• PAYSTACK_CALLBACK_URL

Stripe

• STRIPE_SECRET_KEY
• STRIPE_PUBLIC_KEY
• STRIPE_BASE_URL (optional, defaults to https://api.stripe.com/v1)
• STRIPE_WEBHOOK_SECRET

Monnify

• MONNIFY_API_KEY
• MONNIFY_SECRET_KEY
• MONNIFY_CONTRACT_CODE
• MONNIFY_PUBLIC_KEY (optional)
• MONNIFY_BASE_URL (optional)

Common runtime settings:

• DJANGO_SECRET_KEY
• REDIS_URL
• CACHE_BACKEND

4) Run migrations

python manage.py migrate

---

API Usage

With URLs mounted at /payments/:

• POST /payments/paystack/charge/
• GET /payments/paystack/verify/<reference>/
• POST /payments/webhooks/

Example: initialize charge

curl -X POST http://localhost:8000/payments/paystack/charge/ \
  -H "Content-Type: application/json" \
  -d '{
    "email": "[e-mail]",
    "amount": "1000.00",
    "currency": "NGN",
    "idempotency_key": "trx-20260411103000-abc123",
    "callback_url": "https://example.com/payment/callback"
  }'

Example: verify payment

curl -X GET "http://localhost:8000/payments/paystack/verify/<reference>/"

---

Programmatic Usage

from decimal import Decimal
from payment_infra.infrastructure.providers.registry import get_payment_service

service = get_payment_service()

result = service.process_payment(
    email="[e-mail]",
    amount=Decimal("1000.00"),
    currency="NGN",
    idempotency_key="trx-20260411103000-abc123",
    metadata={"callback_url": "https://example.com/payment/callback"},
)

---

Testing

Run all tests:

pytest

Run only non-integration tests:

pytest -m "not integration"

---

Security Notes

• Always use HTTPS callback/webhook URLs in production.
• Keep provider secret keys in environment variables (never commit them).
• Verify webhook signatures before processing events.
• Use unique idempotency keys per client request to prevent duplicate processing.

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Contributing

1. Create a feature branch.
2. Add/modify tests for changes.
3. Run pytest locally.
4. Open a pull request.

---

License

MIT — see LICENSE.