@clerk/fastify

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Overview

Clerk is the easiest way to add authentication and user management to your Fastify application. To gain a better understanding of the Clerk Backend API and SDK, refer to the Node SDK and Backend API documentation.

Getting Started

To use this plugin you should first create a Clerk application and retrieve a Secret Key and a Publishable Key for you application (see here) to be used as environment variables CLERK_PUBLISHABLE_KEY & CLERK_SECRET_KEY.

Prerequisites

• Node.js >=18.17.0 or later
• Fastify v4+

Installation

npm install @clerk/fastify

Build

npm run build

Usage

Retrieve your Backend API key from the API Keys screen in your Clerk dashboard and set it as an environment variable in a .env file:

CLERK_PUBLISHABLE_KEY=pk_*******
CLERK_SECRET_KEY=sk_******

You will then be able to access all the available methods.

import 'dotenv/config'; // To read CLERK_PUBLISHABLE_KEY
import Fastify from 'fastify';
import { clerkPlugin, getAuth } from '@clerk/fastify';
import type { FastifyInstance } from 'fastify';

const server: FastifyInstance = Fastify({ logger: true });

server.register(clerkPlugin);

server.get('/private', async (req, reply) => {
  const auth = getAuth(req);
  if (!auth.userId) {
    return reply.code(403).send();
  }
  return { hello: 'world' };
});

const start = async () => {
  try {
    await server.listen({ port: 3000 });
  } catch (err) {
    server.log.error(err);
    process.exit(1);
  }
};
start();

Scoped routes

Support authenticated routes that the Clerk middleware will run as plugin in preHandler hook and unauthenticated routes that will not trigger the middleware using the Fastify docs.

import 'dotenv/config'; // To read CLERK_PUBLISHABLE_KEY
import Fastify from 'fastify';
import { clerkPlugin, getAuth } from '@clerk/fastify';
import type { FastifyReply, FastifyRequest, FastifyInstance } from 'fastify';

const server: FastifyInstance = Fastify({ logger: true });

const privateRoutes = async (fastify: FastifyInstance, _opts: any) => {
  fastify.register(clerkPlugin);

  fastify.get('/private', async (req: FastifyRequest, reply: FastifyReply) => {
    const auth = getAuth(req);

    if (!auth.userId) {
      return reply.code(403).send();
    }

    return { hello: 'world', auth };
  });
};

server.register(privateRoutes);

server.get('/public', async (_req, _reply) => {
  return { hello: 'world' };
});

const start = async () => {
  try {
    await server.listen({ port: 3000 });
  } catch (err) {
    server.log.error(err);
    process.exit(1);
  }
};
start();

Support

You can get in touch with us in any of the following ways:

• Join our official community Discord server
• Create a GitHub Discussion
• Contact options listed on our Support page

Contributing

We're open to all community contributions! If you'd like to contribute in any way, please read our contribution guidelines.

Security

@clerk/fastify follows good practices of security, but 100% security cannot be assured.

@clerk/fastify is provided "as is" without any warranty. Use at your own risk.

For more information and to report security issues, please refer to our security documentation.

License

This project is licensed under the MIT license.

See LICENSE for more information.