Use the serve method to define an endpoint that serves a workflow. It provides a context object that you use to create all of your workflow’s steps.

For example, in a Next.js app:

import { serve } from "@upstash/qstash/nextjs"

export const POST = serve(async (context) => {
  const result = await context.run("step-1", async () => {
    // define a piece of business logic as step 1
  })

  await context.run("step-2", async () => {
    // define another piece of business logic as step 2
  })
})

Platform support

Besides Next.js, the serve method supports multiple frameworks and platforms. See all supported platforms here.

Options

failureUrl

Use the failureUrl option to specify a URL your workflow will call if it exhausted all retries and fails.

export const POST = serve<string>(
  async (context) => { ... },
  {
    failureUrl: "https://<YOUR-FAILURE-ENDPOINT>/..."
  }
);

If specified, this URL will be called with the failure callback payload, and the error message will be included in the body field.

The default value is undefined, meaning no failure URL is called.

failureFunction

Use the failureFunction to define a function that’s executed when your workflow exhausts all its retries and fails.

export const POST = serve<string>(
  async (context) => { ... },
  {
    failureFunction: async (
      context,      // context during failure
      failStatus,   // failure status
      failResponse, // failure message
      failHeaders   // failure headers
    ) => {
      // handle the failure
    }
  }
);

If both failureUrl and failureFunction are provided, the failure function takes precedence and the value of failureUrl is ignored.

Note that if you are using a custom authorization method, you should also add authentication to failureFunction.

By default, failureFunction is undefined, meaning that no function is executed on failure.

retries

To specify the number of times QStash will call the workflow endpoint in case of errors, you can use the verbose parameter.

The default value is 3.

export const POST = serve<string>(
  async (context) => { ... },
  {
    retries: 3
  }
);

verbose

To gain insights into how the workflow operates, you can enable verbose mode:

export const POST = serve<string>(
  async (context) => { ... },
  {
    verbose: true
  }
);

Each log entry has the following structure:

{
  timestamp: number,
  workflowRunId: string,
  logLevel: string,
  eventType: string,
  details: unknown,
}

The eventType can be:

  • ENDPOINT_START each time the workflow endpoint is called
  • RUN_SINGLE or RUN_PARALLEL when step(s) are executed
  • SUBMIT_STEP when a single step is executed
  • SUBMIT_FIRST_INVOCATION when a new workflow run starts
  • SUBMIT_CLEANUP when a workflow run finishes
  • SUBMIT_THIRD_PARTY_RESULT when a third-party call result is received (see context.call)

Verbose mode is disabled by default.

initialPayloadParser

When calling the workflow endpoint to start a workflow run, your initial request’s payload is expected to be either empty, a string, or JSON.

If your payload differs, you can process it as needed using the initialPayloadParser option:

type InitialPayload = {
  foo: string
  bar: number
}

// 👇 1: provide initial payload type
export const POST = serve<InitialPayload>(
  async (context) => {
    // 👇 3: parsing result is available as requestPayload
    const payload: InitialPayload = context.requestPayload
  },
  {
    // 👇 2: custom parsing for initial payload
    initialPayloadParser: (initialPayload) => {
      const payload: InitialPayload =
        parsePayload(initialPayload)
      return payload
    },
  }
)

url

Since a workflow run involves multiple calls to the workflow endpoint, the serve method needs to know where your endpoint is hosted.

Typically, your workflow infers this using the request.url field.

However, if you use a proxy or a local tunnel for development, you may want to override the URL inferred from request.url:

export const POST = serve<string>(
  async (context) => { ... },
  {
    url: "https://<YOUR-DEPLOYED-APP>.com/api/workflow"
  }
);

By default, url is undefined, and the URL is inferred from request.url.

baseUrl

An alternative to the url option is the baseUrl option. While url replaces the entire URL inferred from request.url, baseUrl only changes the base of the URL:

export const POST = serve<string>(
  async (context) => {
    ...
  },
  // options:
  {
    baseUrl: "<LOCAL-TUNNEL-PUBLIC-URL>"
  }
);

The default value of baseUrl is undefined.

If you have multiple endpoints and you don’t want to set baseUrl in every single one, you can set the UPSTASH_WORKFLOW_URL environment variable to apply baseUrl across your entire application.

Setting this environment variable is especially useful during local development. In production, baseUrl or UPSTASH_WORKFLOW_URL are not necessary.


Further options

The following options can be considered convenience methods. They are intended to support edge cases or testing pipelines and are not required for regular use.

qstashClient

The qstashClient option allows you to pass a QStash Client explicitly. This can be helpful when using multiple QStash clients in the same project with different environment variables.

import { Client } from "@upstash/qstash";
import { serve } from "@upstash/qstash/nextjs";

export const POST = serve(
  async (context) => { ... },
  {
    qstashClient: new Client({ token: process.env.QSTASH_TOKEN })
  }
);

By default, a qstashClient is initialized as:

new Client({
  baseUrl: process.env.QSTASH_URL!,
  token: process.env.QSTASH_TOKEN!,
})

receiver

You can pass a QStash Receiver to verify that every request the endpoint receives comes from QStash, preventing anyone from triggering your workflow.

import { Receiver } from "@upstash/qstash";
import { serve } from "@upstash/qstash/nextjs";

export const POST = serve<string>(
  async (context) => { ... },
  {
    receiver: new Receiver({
      // 👇 grab these variables from your QStash dashboard
      currentSigningKey: process.env.QSTASH_CURRENT_SIGNING_KEY!,
      nextSigningKey: process.env.QSTASH_NEXT_SIGNING_KEY!,
    })
  }
);

The default receiver is automatically used if the environment variables QSTASH_CURRENT_SIGNING_KEY and QSTASH_NEXT_SIGNING_KEY are set. If you want to turn off the Receiver, remove these environment variables or pass receiver: undefined in the options. Note that this will skip any verification that requests are coming from QStash and allow anyone to start your workflow.

env

By default, the SDK uses process.env to initialize the QStash client and the receiver (if the two environment variables are set). If process.env doesn’t exist, the SDK won’t be able to access the environment variables. In this case, you can either pass qstashClient and receiver options or use the env option.

If you pass env, this env will be used instead of process.env:

import { Receiver } from "@upstash/qstash";
import { serve } from "@upstash/qstash/nextjs";

export const POST = serve<string>(
  async (context) => {
    // the env option will be available in the env field of the context:
    const env = context.env;
  },
  {
    receiver: new Receiver({
      // 👇 grab these variables from your QStash dashboard
      currentSigningKey: process.env.QSTASH_CURRENT_SIGNING_KEY!,
      nextSigningKey: process.env.QSTASH_NEXT_SIGNING_KEY!,
    })
  }
);