Payment receipt email: template and code

COURIER_API_KEY=pk_... node --experimental-strip-types setup.ts

// Email a receipt and add a copy to your app's Inbox after a successful
// payment, with the template ID setup.ts printed. The receipt number is the
// idempotency key, so a retried payment webhook doesn't send a second receipt.
// Courier keeps a key for 25 hours unless you set an expiration, and Stripe
// retries a failed webhook for up to three days, so the key is held for four.
// The "receipt" tag lets an Inbox tab show receipts on your billing page. The
// templates format paidAt as a date, show every amount (integer cents, as
// Stripe sends them) as dollars, and build the receipt link from the receipt
// number.
import Courier from "@trycourier/courier";

const client = new Courier();
const DAY = 24 * 60 * 60 * 1000;

export interface Receipt {
  receiptNumber: string;
  paidAt: Date;
  paymentMethod: string;
  lineItems: { name: string; amount: number }[];
  subtotal: number;
  tax: number;
  total: number;
}

export async function sendReceipt(
  templateId: string,
  userId: string,
  receipt: Receipt
) {
  const { requestId } = await client.send.message({
    message: {
      to: { user_id: userId },
      template: templateId,
      data: {
        receipt_number: receipt.receiptNumber,
        paid_at: receipt.paidAt.toISOString(),
        payment_method: receipt.paymentMethod,
        line_items: receipt.lineItems,
        subtotal: receipt.subtotal,
        tax: receipt.tax,
        total: receipt.total,
      },
      routing: { method: "all", channels: ["email", "inbox"] },
      metadata: { tags: ["receipt"] },
    },
    "Idempotency-Key": `receipt-${receipt.receiptNumber}`,
    "x-idempotency-expiration": new Date(Date.now() + 4 * DAY).toISOString(),
  });
  return requestId;
}

# Email a receipt and add a copy to your app's Inbox after a successful
# payment, with the template ID setup.ts printed. The receipt number is the
# idempotency key, so a retried payment webhook doesn't send a second receipt.
# Courier keeps a key for 25 hours unless you set an expiration, and Stripe
# retries a failed webhook for up to three days, so the key is held for four.
# The "receipt" tag lets an Inbox tab show receipts on your billing page. The
# templates format paid_at as a date, show every amount (int cents, as Stripe
# sends them) as dollars, and build the receipt link from the receipt number.
from datetime import datetime, timedelta, timezone

from courier import Courier

client = Courier()


def send_receipt(
    template_id: str,
    user_id: str,
    receipt_number: str,
    paid_at: datetime,
    payment_method: str,
    line_items: list[dict],  # [{"name": str, "amount": int}], amounts in cents
    subtotal: int,
    tax: int,
    total: int,
) -> str:
    response = client.send.message(
        message={
            "to": {"user_id": user_id},
            "template": template_id,
            "data": {
                "receipt_number": receipt_number,
                "paid_at": paid_at.isoformat(),
                "payment_method": payment_method,
                "line_items": line_items,
                "subtotal": subtotal,
                "tax": tax,
                "total": total,
            },
            "routing": {"method": "all", "channels": ["email", "inbox"]},
            "metadata": {"tags": ["receipt"]},
        },
        idempotency_key=f"receipt-{receipt_number}",
        x_idempotency_expiration=(
            datetime.now(timezone.utc) + timedelta(days=4)
        ).isoformat(),
    )
    return response.request_id