Upstash Qstash JS

Receiver - Message Verification

Overview

The Receiver class verifies that incoming requests are genuinely from QStash by validating JWT signatures. This prevents unauthorized requests from reaching your endpoints.

Getting Your Signing Keys

Sign in to the Upstash Console and navigate to your QStash instance to find:

• Current Signing Key: Active key for signature verification

• Next Signing Key: Key to use after rotation

Store these as environment variables:

QSTASH_CURRENT_SIGNING_KEY="your_current_key"
QSTASH_NEXT_SIGNING_KEY="your_next_key"

Creating a Receiver Instance

Basic Setup

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

const receiver = new Receiver({
  currentSigningKey: process.env.QSTASH_CURRENT_SIGNING_KEY!,
  nextSigningKey: process.env.QSTASH_NEXT_SIGNING_KEY!,
});

Multi-Region Mode

If you're using multi-region QStash (with QSTASH_REGION environment variable set), signature verification requires additional configuration. The SDK automatically detects the region from the upstash-region header and uses region-specific signing keys.

Important: Multi-region signature verification requires careful setup. See Multi-Region Setup for complete details on environment variables, region detection, and verification strategies.

Verifying Incoming Requests

Basic Verification

try {
  await receiver.verify({
    signature: request.headers.get("upstash-signature")!,
    body: await request.text(),
  });

  // Request is valid - process it
  return new Response("OK", { status: 200 });
} catch (error) {
  // Invalid signature
  return new Response("Unauthorized", { status: 401 });
}

With URL Verification

For extra security, verify the request was sent to the correct URL:

await receiver.verify({
  signature: request.headers.get("upstash-signature")!,
  body: await request.text(),
  url: "https://my-api.example.com/webhook",
});

With Clock Tolerance

Handle minor clock differences between servers:

await receiver.verify({
  signature: request.headers.get("upstash-signature")!,
  body: await request.text(),
  clockTolerance: 5, // Allow 5 seconds difference
});

Required Headers

QStash sends these headers with every request:

• Upstash-Signature: JWT signature to verify

Note: In multi-region mode, QStash also sends an Upstash-Region header. See Multi-Region Setup for details.

Handling Verification Failures

SignatureError

The verify() method throws SignatureError for invalid signatures:

import { Receiver, SignatureError } from "@upstash/qstash";

try {
  await receiver.verify({
    signature: request.headers.get("upstash-signature")!,
    body: await request.text(),
  });
} catch (error) {
  if (error instanceof SignatureError) {
    console.error("Invalid signature:", error.message);
    return new Response("Invalid signature", { status: 401 });
  }
  throw error;
}

Common Failure Reasons

1. Missing or wrong signing keys

   • Verify keys in Upstash Console match environment variables

2. Body mismatch

   • Ensure you pass the raw request body (not parsed JSON)

   • Don't modify the body before verification

3. Expired signature

   • QStash signatures expire after 5 minutes

   • Check server clock is synchronized

   • Use clockTolerance if needed

4. URL mismatch

   • Ensure the url parameter matches the destination URL

   • Include protocol, domain, and path

Key Rotation

The Receiver supports seamless key rotation:

1. Verification tries currentSigningKey first

2. If that fails, tries nextSigningKey

3. Only throws error if both fail

To rotate keys:

1. Set new key as QSTASH_NEXT_SIGNING_KEY

2. Wait for all in-flight requests to complete

3. Update QSTASH_CURRENT_SIGNING_KEY to the new key

4. Generate a new QSTASH_NEXT_SIGNING_KEY

Best Practices

Always Verify

Never trust incoming requests without verification:

// ❌ Don't do this
app.post("/webhook", async (req) => {
  const data = await req.json();
  processWebhook(data); // Unverified!
});

// ✅ Do this
app.post("/webhook", async (req) => {
  const body = await req.text();

  await receiver.verify({
    signature: req.headers.get("upstash-signature")!,
    body,
  });

  const data = JSON.parse(body);
  processWebhook(data);
});

Use Environment Variables

Never hardcode signing keys:

// ❌ Don't do this
const receiver = new Receiver({
  currentSigningKey: "sig_abc123...",
});

// ✅ Do this
const receiver = new Receiver({
  currentSigningKey: process.env.QSTASH_CURRENT_SIGNING_KEY!,
  nextSigningKey: process.env.QSTASH_NEXT_SIGNING_KEY!,
});

Read Body Once

Request bodies can only be read once. Save it for reuse:

const body = await request.text();

// Verify with raw body
await receiver.verify({
  signature: request.headers.get("upstash-signature")!,
  body,
});

// Parse after verification
const data = JSON.parse(body);

Platform-Specific Verification

For framework-specific implementations, see:

• Next.js Verification