Payment Retries

This example demonstrates a payment retry process using Upstash Workflow. The following example handles retrying a payment, sending emails, and suspending accounts.

Use Case

Our workflow will:

1. Attempt to process a payment
2. Retry the payment if it fails with a 24-hour delay
3. If the payment succeeds:
   • Unsuspend the user’s account if it was suspended
   • Send an invoice email
4. If the payment fails after 3 retries:
   • Suspend the user’s account

Code Example

api/workflow/route.ts

import { serve } from "@upstash/workflow/nextjs";

type ChargeUserPayload = {
  email: string;
};

export const { POST } = serve<ChargeUserPayload>(async (context) => {
  const { email } = context.requestPayload;

  for (let i = 0; i < 3; i++) {
    // attempt to charge the user
    const result = await context.run("charge customer", async () => {
      try {
        return await chargeCustomer(i + 1),
      } catch (e) {
        console.error(e);
        return
      }
    });

    if (!result) {
      // Wait for a day
      await context.sleep("wait for retry", 24 * 60 * 60);
    } else {
      // Unsuspend User
      const isSuspended = await context.run("check suspension", async () => {
        return await checkSuspension(email);
      });
      if (isSuspended) {
        await context.run("unsuspend user", async () => {
          await unsuspendUser(email);
        });
      }

      // send invoice email
      await context.run("send invoice email", async () => {
        await sendEmail(
          email,
          `Payment successfull. Incoice: ${result.invoiceId}, Total cost: $${result.totalCost}`
        );
      });

      // by retuning, we end the workflow run
      return;
    }
  }

  // suspend user if the user isn't suspended
  const isSuspended = await context.run("check suspension", async () => {
    return await checkSuspension(email);
  });

  if (!isSuspended) {
    await context.run("suspend user", async () => {
      await suspendUser(email);
    });

    await context.run("send suspended email", async () => {
      await sendEmail(
        email,
        "Your account has been suspended due to payment failure. Please update your payment method."
      );
    });
  }
});

async function sendEmail(email: string, content: string) {
  // Implement the logic to send an email
  console.log("Sending email to", email, "with content:", content);
}

async function checkSuspension(email: string) {
  // Implement the logic to check if the user is suspended
  console.log("Checking suspension status for", email);
  return true;
}

async function suspendUser(email: string) {
  // Implement the logic to suspend the user
  console.log("Suspending the user", email);
}

async function unsuspendUser(email: string) {
  // Implement the logic to unsuspend the user
  console.log("Unsuspending the user", email);
}

async function chargeCustomer(attempt: number) {
  // Implement the logic to charge the customer
  console.log("Charging the customer");

  if (attempt <= 2) {
    throw new Error("Payment failed");
  }

  return {
    invoiceId: "INV123",
    totalCost: 100,
  } as const;
}

Code Breakdown

1. Charge Customer

We attempt to charge the customer:

const result = await context.run("charge customer", async () => {
  try {
    return await chargeCustomer(i + 1),
  } catch (e) {
    console.error(e);
    return
  }
});

If we haven’t put a try-catch block here, the workflow would still have retried the step. Hovewer, because we want to run custom logic when the payment fails, we catch the error here.

2. Retry Payment

We try to charge the customer 3 times with a 24-hour delay between each attempt:

for (let i = 0; i < 3; i++) {
  // attempt to charge the customer

  if (!result) {
    // Wait for a day
    await context.sleep("wait for retry", 24 * 60 * 60);  
  } else {
    // Payment succeeded
    // Unsuspend user, send invoice email
    // end the workflow:
    return;
  }
}

3. If Payment Succeeds

3.1. Unsuspend User

We check if the user is suspended and unsuspend them if they are:

const isSuspended = await context.run("check suspension", async () => {
  return await checkSuspension(email);
});
if (isSuspended) {
  await context.run("unsuspend user", async () => {
    await unsuspendUser(email);
  });
}

3.2. Send Invoice Email

We send an invoice we got from the payment step to the user:

await context.run("send invoice email", async () => {
  await sendEmail(
    email,
    `Payment successfull. Incoice: ${result.invoiceId}, Total cost: $${result.totalCost}`
  );
});

One of the biggest advantages of using Upstash Workflow is that you have access to the result of the previous steps. This allows you to pass data between steps without having to store it in a database.

4. If Payment Fails After 3 Retries

4.1. Suspend User

If the payment fails after 3 retries, we suspend the user and send them an email to notify them:

const isSuspended = await context.run("check suspension", async () => {
  return await checkSuspension(email);
});

if (!isSuspended) {
  await context.run("suspend user", async () => {
    await suspendUser(email);
  });

  await context.run("send suspended email", async () => {
    await sendEmail(
      context.requestPayload.email,
      "Your account has been suspended due to payment failure. Please update your payment method."
    );
  });
}