Ebook download

This flow keeps payment, download ownership, and optional email delivery as separate durable facts.

import {
  Billing,
  DownloadEmails,
  Downloads,
  Offer,
  Purchase,
  authorizeDownload,
  createCheckout,
  processPaymentNotification,
  registerOffers,
} from "@byfungsi/sapa";
import { Effect } from "effect";

const ebookDownload =
  yield *
  Downloads.download({
    asset: { key: "ebook.effect.pdf", revision: 1 },
    duration: "perpetual",
  });
const ebookEmail =
  yield *
  DownloadEmails.customer({
    asset: { key: "ebook.effect.pdf", revision: 1 },
  });
const ebookPurchase =
  yield *
  Purchase.parse({
    key: "ebook.effect.benefits",
    revision: 1,
    provides: [ebookDownload, ebookEmail],
  });
const ebookBilling =
  yield *
  Billing.oneTime({
    price: { currency: "IDR", amount: 99_000n },
  });
const ebook =
  yield *
  Offer.parse({
    key: "ebook.effect",
    revision: 1,
    purchase: ebookPurchase,
    billing: ebookBilling,
  });

yield * registerOffers([ebook]);

const checkout =
  yield *
  createCheckout({
    type: "offer",
    offerKey: ebook.key,
    offerRevision: ebook.revision,
    quantity: null,
    provider: "midtrans",
    customer: {
      externalId: "customer-42",
      email: "buyer@example.com",
      name: "Example Buyer",
    },
    successUrl: "https://merchant.example/orders/success",
    cancelUrl: "https://merchant.example/orders/canceled",
    clientIp: null,
    idempotencyKey: "ebook-order-42",
  });

// Redirect the browser to checkout.url. Later, in the webhook handler:
const settlement =
  yield *
  processPaymentNotification({
    provider: "midtrans",
    payload: rawProviderPayload,
  });

if (settlement.status === "settled") {
  // Run the deployment's fulfillment/email worker independently.
}

// In a later authenticated customer request:
const download =
  yield *
  authorizeDownload({
    externalCustomerId: "customer-42",
    asset: { key: "ebook.effect.pdf", revision: 1 },
  });

Install asset revision ebook.effect.pdf@1 before registration. Return download.url only after your host authenticates that the caller owns customer-42. The URL is bounded by both the configured link lifetime and the historical eligibility end. A refund makes subsequent authorization fail even if email delivery is still retrying.

See Downloads for asset adapter and signed-link requirements.