💳 Stripe API

Typ: REST API
Auth: API Key (Secret + Publishable)
Status: ✅ Marktführer Payments

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Übersicht

Stripe für: - Miet-Zahlungen (wiederkehrend) - Einmalzahlungen (Kaution, NK-Nachzahlung) - Zahlungsaufforderungen per Link - Automatisches Mahnwesen

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API Endpoints

Methode	Endpunkt	Beschreibung	Cache TTL
GET	/api/payments/customers	Alle Kunden	5min
GET	/api/payments/customers/:id	Kundendetails	1min
POST	/api/payments/customers	Kunde anlegen	-
GET	/api/payments/subscriptions	Abos (Mieten)	1min
POST	/api/payments/subscriptions	Abo erstellen	-
POST	/api/payments/invoices	Rechnung erstellen	-
POST	/api/payments/payment-links	Zahlungslink	-
GET	/api/payments/balance	Kontostand	5min
GET	/api/payments/transactions	Transaktionen	1min

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Stripe Integration

import Stripe from 'stripe';

const stripe = new Stripe(process.env.STRIPE_SECRET_KEY);

// Mieter als Kunde anlegen
async function createTenantCustomer(tenant: {
  name: string;
  email: string;
  phone?: string;
  address: string;
}) {
  return stripe.customers.create({
    name: tenant.name,
    email: tenant.email,
    phone: tenant.phone,
    address: {
      line1: tenant.address,
      country: 'DE'
    },
    metadata: {
      tenantId: tenant.id,
      propertyId: tenant.propertyId
    }
  });
}

// Wiederkehrende Mietzahlung (Subscription)
async function createRentSubscription(
  customerId: string,
  rentAmount: number,  // in Cents
  startDate: Date
) {
  // Produkt für die Wohnung
  const product = await stripe.products.create({
    name: `Miete Wohnung ${unitId}`,
    metadata: { unitId }
  });

  // Preis (monatlich)
  const price = await stripe.prices.create({
    product: product.id,
    unit_amount: rentAmount,
    currency: 'eur',
    recurring: {
      interval: 'month',
      interval_count: 1
    }
  });

  // Subscription
  return stripe.subscriptions.create({
    customer: customerId,
    items: [{ price: price.id }],
    billing_cycle_anchor: Math.floor(startDate.getTime() / 1000),
    payment_settings: {
      payment_method_types: ['sepa_debit', 'card']
    },
    metadata: { unitId, type: 'rent' }
  });
}

// Einmalzahlung (Kaution, NK)
async function createOneTimePayment(
  customerId: string,
  amount: number,
  description: string
) {
  const invoice = await stripe.invoices.create({
    customer: customerId,
    auto_advance: true,
    collection_method: 'send_invoice',
    days_until_due: 14
  });

  await stripe.invoiceItems.create({
    customer: customerId,
    invoice: invoice.id,
    amount,
    currency: 'eur',
    description
  });

  return stripe.invoices.sendInvoice(invoice.id);
}

// Zahlungslink für schnelle Zahlung
async function createPaymentLink(
  amount: number,
  description: string,
  tenantEmail: string
) {
  const price = await stripe.prices.create({
    unit_amount: amount,
    currency: 'eur',
    product_data: {
      name: description
    }
  });

  return stripe.paymentLinks.create({
    line_items: [{ price: price.id, quantity: 1 }],
    after_completion: {
      type: 'redirect',
      redirect: { url: 'https://app.example.com/payment-success' }
    },
    metadata: { tenantEmail }
  });
}

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Webhook Handler

app.post('/webhooks/stripe', async (req, res) => {
  const sig = req.headers['stripe-signature'];
  const event = stripe.webhooks.constructEvent(
    req.body,
    sig,
    process.env.STRIPE_WEBHOOK_SECRET
  );

  switch (event.type) {
    case 'invoice.paid':
      await recordPayment(event.data.object);
      break;

    case 'invoice.payment_failed':
      await handlePaymentFailure(event.data.object);
      break;

    case 'customer.subscription.deleted':
      await handleSubscriptionCancelled(event.data.object);
      break;
  }

  res.json({ received: true });
});

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Umgebungsvariablen

# Stripe
STRIPE_SECRET_KEY="sk_live_..."
STRIPE_PUBLISHABLE_KEY="pk_live_..."
STRIPE_WEBHOOK_SECRET="whsec_..."

# Test-Modus
STRIPE_TEST_SECRET_KEY="sk_test_..."
STRIPE_TEST_PUBLISHABLE_KEY="pk_test_..."

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Marktführer • SEPA + Karte • Subscriptions • Webhooks