Digital Goods API と Payment Request API を使用して Google Play 請求サービス経由で支払いを受け取る

  ...,
  "enableNotifications": true,
  "features": {
    "playBilling": {
      "enabled": true
    }
  },
  "alphaDependencies": {
    "enabled": true
  },
  ...

if ('getDigitalGoodsService' in window) {
 // Digital Goods API is supported!
}

if ('getDigitalGoodsService' in window) {
  // Digital Goods API is supported!
  try {
    const service =
        await window.getDigitalGoodsService('https://play.google.com/billing');
    // Google Play Billing is supported!

  } catch (error) {
    // Google Play Billing is not available. Use another payment flow.
    return;
  }
}

const skuDetails = await service.getDetails(['shiny_sword', 'gem']);
for (item of skuDetails) {
  // Format the price according to the user locale.
  const localizedPrice = new Intl.NumberFormat(
      navigator.language,
      {style: 'currency', currency: item.price.currency}
    ).format(item.price.value);

  // Render the price to the UI.
  renderProductDetails(
        item.itemId, item.title, localizedPrice, item.description);
}

async function makePurchase(service, sku) {
   // Define the preferred payment method and item ID
   const paymentMethods = [{
       supportedMethods: "https://play.google.com/billing",
       data: {
           sku: sku,
       }
   }];

   ...
}

const paymentDetails = {
    total: {
        label: `Total`,
        amount: {currency: `USD`, value: `0`}
    }
};

const request = new PaymentRequest(paymentMethods, paymentDetails);

...
const request = new PaymentRequest(paymentMethods, paymentDetails);
try {
    const paymentResponse = await request.show();
    const {purchaseToken} = paymentResponse.details;

    // Call backend to validate and acknowledge the purchase.
    if (await acknowledgePurchaseOnBackend(purchaseToken, sku)) {
        // Optional: tell the PaymentRequest API the validation was
        // successful. The user-agent may show a "payment successful"
        // message to the user.
        const paymentComplete = await paymentResponse.complete('success');
    } else {
        // Optional: tell the PaymentRequest API the validation failed. The
        // user agent may show a message to the user.
        const paymentComplete = await paymentResponse.complete('fail');
    }
} catch(e) {
    // The purchase failed, and we can handle the failure here. AbortError
    // usually means a user cancellation
}
...

async function makePurchase(service, sku) {
    // Define the preferred payment method and item ID
    const paymentMethods = [{
        supportedMethods: "https://play.google.com/billing",
        data: {
            sku: sku,
        }
    }];

    // The "total" member of the paymentDetails is required by the Payment
    // Request API, but is not used when using Google Play Billing. We can
    // set it up with bogus details.
    const paymentDetails = {
        total: {
            label: `Total`,
            amount: {currency: `USD`, value: `0`}
        }
    };

    const request = new PaymentRequest(paymentMethods, paymentDetails);
    try {
        const paymentResponse = await request.show();
        const {purchaseToken} = paymentResponse.details;

        // Call backend to validate and acknowledge the purchase.
        if (await acknowledgePurchaseOnBackend(purchaseToken, sku)) {
            // Optional: consume the purchase, allowing the user to purchase
            // the same item again.
            service.consume(purchaseToken);

            // Optional: tell the PaymentRequest API the validation was
            // successful. The user-agent may show a "payment successful"
            // message to the user.
            const paymentComplete =
                    await paymentResponse.complete('success');
        } else {
            // Optional: tell the PaymentRequest API the validation failed.
            // The user agent may show a message to the user.
            const paymentComplete = await paymentResponse.complete('fail');
        }
    } catch(e) {
        // The purchase failed, and we can handle the failure here.
        // AbortError usually means a user cancellation
    }
}

const service =
     await window.getDigitalGoodsService('https://play.google.com/billing');
...
const existingPurchases = await service.listPurchases();
for (const p of existingPurchases) {
    // Update the UI with items the user is already entitled to.
    console.log(`Users has entitlement for ${p.itemId}`);
}

const service =
     await window.getDigitalGoodsService("https://play.google.com/billing");
...
const existingPurchases = await service.listPurchases();
for (const p of existingPurchases) {
    await verifyOrAcknowledgePurchaseOnBackend(p.purchaseToken, p.itemId);

    // Update the UI with items the user is already entitled to.
    console.log(`Users has entitlement for ${p.itemId}`);
}