Introduction

This example demonstrates an automated e-commerce order fulfillment process using Upstash Workflow. The workflow takes an order, verifies the stock, processes the payment, and handles order dispatch and customer notifications.

Use Case

Our workflow will:

  1. Receive an order request
  2. Verify the availability of the items in stock
  3. Process the payment
  4. Initiate the dispatch of the order
  5. Send confirmation and delivery notifications to the customer

Code Example

api/workflow/route.ts
import { serve } from "@upstash/workflow/nextjs"
import {
  createOrderId,
  checkStockAvailability,
  processPayment,
  dispatchOrder,
  sendOrderConfirmation,
  sendDispatchNotification,
} from "./utils"

type OrderPayload = {
  userId: string
  items: { productId: string, quantity: number }[]
}

export const { POST } = serve<OrderPayload>(async (context) => {
  const { userId, items } = context.requestPayload;

  // Step 1: Create Order Id
  const orderId = await context.run("create-order-id", async () => {
    return await createOrderId(userId);
  });

  // Step 2: Verify stock availability
  const stockAvailable = await context.run("check-stock", async () => {
    return await checkStockAvailability(items);
  });

  if (!stockAvailable) {
    console.warn("Some items are out of stock");
    return;
  };

  // Step 3: Process payment
  await context.run("process-payment", async () => {
    return await processPayment(orderId)
  })

  // Step 4: Dispatch the order
  await context.run("dispatch-order", async () => {
    return await dispatchOrder(orderId, items)
  })

  // Step 5: Send order confirmation email
  await context.run("send-confirmation", async () => {
    return await sendOrderConfirmation(userId, orderId)
  })

  // Step 6: Send dispatch notification
  await context.run("send-dispatch-notification", async () => {
    return await sendDispatchNotification(userId, orderId)
  })
})

Code Breakdown

1. Verifying Stock Availability

We start by creating an order id and verifying if the items in the order are available in stock. If not, we throw an error to halt the process:

api/workflow/route.ts
const orderId = await context.run("create-order-id", async () => {
  return await createOrderId(userId);
});

const stockAvailable = await context.run("check-stock", async () => {
  return await checkStockAvailability(items)
})

if (!stockAvailable) {
  console.warn("Some items are out of stock")
  return;
}

2. Processing Payment

Once the stock is verified, the workflow processes the payment for the order:

api/workflow/route.ts
await context.run("process-payment", async () => {
  return await processPayment(orderId)
})

3. Dispatching the Order

After payment confirmation, we dispatch the order for delivery:

api/workflow/route.ts
await context.run("dispatch-order", async () => {
  return await dispatchOrder(orderId, items)
})

4. Sending Confirmation and Notification Emails

Lastly, we send an order confirmation email to the customer and notify them when the order is dispatched:

api/workflow/route.ts
await context.run("send-confirmation", async () => {
  return await sendOrderConfirmation(userId, orderId)
})

await context.run("send-dispatch-notification", async () => {
  return await sendDispatchNotification(userId, orderId)
})

Key Features

  1. Stock Verification: Ensures items are available in stock before processing the payment, avoiding issues with unavailable products.

  2. Payment Processing: Handles payment securely and only proceeds to dispatch if successful.

  3. Customer Notifications: Keeps the customer informed at each step of the order process, improving user experience.