---
title: "Add JWT Authentication to Your undefined API"
description: undefined
canonicalUrl: "https://zuplo.com/use-cases/api-key-auth/javascript/restify/jwt-backend"
framework: undefined
language: undefined
authStrategy: "JWT with JWKS"
pageType: use-case
---

# Add JWT Authentication to Your undefined API



## How Zuplo Handles It

Let Zuplo issue short-lived JWTs signed with a JWKS your undefined backend can verify — no long-lived API keys touch your origin.

## undefined Backend Code

```javascript
const restify = require("restify");
const jwt = require("jsonwebtoken");
const jwksClient = require("jwks-rsa");

// ISSUER URL
const ISSUER = "https://my-api-a32f34.zuplo.api/__zuplo/issuer";

// Set up JWKS client
const client = jwksClient({
  jwksUri: `${ISSUER}/.well-known/jwks.json`,
  cache: true,
  cacheMaxAge: 600000, // 10 minutes
});

// Function to retrieve the signing key
function getKey(header, callback) {
  client.getSigningKey(header.kid, function (err, key) {
    if (err) {
      return callback(err);
    }
    const signingKey = key.getPublicKey();
    callback(null, signingKey);
  });
}

// JWT validation middleware
function validateJwt(req, res, next) {
  const token = req.headers.authorization?.replace("Bearer ", "");

  if (!token) {
    return res.send(401, { error: "No token provided" });
  }

  jwt.verify(
    token,
    getKey,
    {
      issuer: ISSUER,
      algorithms: ["RS256"],
    },
    (err, decoded) => {
      if (err) {
        return res.send(401, { error: "Invalid token", details: err.message });
      }
      req.user = decoded;
      next();
    },
  );
}

// Create Restify server
const server = restify.createServer();

// Use middleware
server.use(restify.plugins.queryParser());
server.use(validateJwt);

// Protected route example
server.get("/protected", (req, res, next) => {
  res.send({
    message: "Access granted",
    user: req.user,
  });
  return next();
});

// Start the server
server.listen(8080, () => {
  console.log("%s listening at %s", server.name, server.url);
});
```

## Example Request

```bash
curl -X GET \
  'https://your-api.zuplo.dev/your-route' \
  -H 'Authorization: Bearer YOUR_API_KEY'
```

## Learn More

- [API Key Authentication on Zuplo](https://zuplo.com/docs/policies/api-key-auth-inbound)
- [JWT Authentication on Zuplo](https://zuplo.com/docs/policies/open-id-jwt-auth-inbound)
- [All use cases](https://zuplo.com/use-cases)