Stripe Integration

# Stripe Integration

Master Stripe payment processing integration for robust, PCI-compliant payment flows including checkout, subscriptions, webhooks, and refunds.

## Do not use this skill when

- The task is unrelated to stripe integration
- You need a different domain or tool outside this scope

## Instructions

- Clarify goals, constraints, and required inputs.
- Apply relevant best practices and validate outcomes.
- Provide actionable steps and verification.
- If detailed examples are required, open `resources/implementation-playbook.md`.

## Use this skill when

- Implementing payment processing in web/mobile applications
- Setting up subscription billing systems
- Handling one-time payments and recurring charges
- Processing refunds and disputes
- Managing customer payment methods
- Implementing SCA (Strong Customer Authentication) for European payments
- Building marketplace payment flows with Stripe Connect

## Core Concepts

### 1. Payment Flows
**Checkout Session (Hosted)**
- Stripe-hosted payment page
- Minimal PCI compliance burden
- Fastest implementation
- Supports one-time and recurring payments

**Payment Intents (Custom UI)**
- Full control over payment UI
- Requires Stripe.js for PCI compliance
- More complex implementation
- Better customization options

**Setup Intents (Save Payment Methods)**
- Collect payment method without charging
- Used for subscriptions and future payments
- Requires customer confirmation

### 2. Webhooks
**Critical Events:**
- `payment_intent.succeeded`: Payment completed
- `payment_intent.payment_failed`: Payment failed
- `customer.subscription.updated`: Subscription changed
- `customer.subscription.deleted`: Subscription canceled
- `charge.refunded`: Refund processed
- `invoice.payment_succeeded`: Subscription payment successful

### 3. Subscriptions
**Components:**
- **Product**: What you're selling
- **Price**: How much and how often
- **Subscription**: Customer's recurring payment
- **Invoice**: Generated for each billing cycle

### 4. Customer Management
- Create and manage customer records
- Store multiple payment methods
- Track customer metadata
- Manage billing details

## Quick Start

```python
import stripe

stripe.api_key = "sk_test_..."

# Create a checkout session
session = stripe.checkout.Session.create(
    payment_method_types=['card'],
    line_items=[{
        'price_data': {
            'currency': 'usd',
            'product_data': {
                'name': 'Premium Subscription',
            },
            'unit_amount': 2000,  # $20.00
            'recurring': {
                'interval': 'month',
            },
        },
        'quantity': 1,
    }],
    mode='subscription',
    success_url='https://yourdomain.com/success?session_id={CHECKOUT_SESSION_ID}',
    cancel_url='https://yourdomain.com/cancel',
)

# Redirect user to session.url
print(session.url)
```

## Payment Implementation Patterns

### Pattern 1: One-Time Payment (Hosted Checkout)
```python
def create_checkout_session(amount, currency='usd'):
    """Create a one-time payment checkout session."""
    try:
        session = stripe.checkout.Session.create(
            payment_method_types=['card'],
            line_items=[{
                'price_data': {
                    'currency': currency,
                    'product_data': {
                        'name': 'Purchase',
                        'images': ['https://example.com/product.jpg'],
                    },
                    'unit_amount': amount,  # Amount in cents
                },
                'quantity': 1,
            }],
            mode='payment',
            success_url='https://yourdomain.com/success?session_id={CHECKOUT_SESSION_ID}',
            cancel_url='https://yourdo