Clerk Node.js SDK

Setting up Clerk Node.js

Create a Clerk application

You need to create a Clerk application in your Clerk Dashboard before you can set up Clerk Node.js. For more information, check out our Set up your application guide.

Install Clerk Node.js

Once a Clerk application has been created, you can install and then start using Clerk Node.js in your application. An ES module for the Clerk Node SDK is available under the @clerk/clerk-sdk-node npm package.

terminal
npm install @clerk/clerk-sdk-node

terminal
yarn add @clerk/clerk-sdk-node

terminal
pnpm add @clerk/clerk-sdk-node

Set environment keys

Below is an example of an .env.local file. If you are signed into your Clerk Dashboard, your keys should become visible by clicking on the eye icon.

.env.local
CLERK_SECRET_KEY={{secret}}

Resources

All resource operations are mounted as sub-APIs on the Clerk class. For more information, check out the Clerk Backend SDK documentation.

Customizing resources

The following options are available for you to customize the behaviour of the Clerk class.

Most options can also be set as environment variables so that you don't need to pass anything to the constructor or set it via the available setters.

Option	Description	Default	Environment variable
`secretKey`	Server key for `api.clerk.com`	none	`CLERK_SECRET_KEY`
`apiVersion`	for future use, `v1` for now	`v1`	`CLERK_API_VERSION`
`serverApiURL`	for debugging / future use	`https://api.clerk.com`	`CLERK_API_URL`
`httpOptions`	http client options	`{}`	N/A

For every option the resolution is as follows, in order of descending precedence:

option passed
environment variable (if applicable)
default

Another available environment variable is CLERK_LOGGING. You can set its value to true to enable additional logging that may be of use when debugging an issue.

Singleton

If you are comfortable with setting the CLERK_SECRET_KEY environment variable and being finished, the default instance created by the SDK will suffice for your needs.


import clerk from '@clerk/clerk-sdk-node';
 
const userList = await clerk.users.getUserList();

Or if you are interested only in a certain resource:


import { sessions } from '@clerk/clerk-sdk-node';
 
const sessionList = await sessions.getSessionList();


const pkg = require('@clerk/clerk-sdk-node');
const clerk = pkg.default;
 
clerk.emails
  .createEmail({ fromEmailName, subject, body, emailAddressId })
  .then((email) => console.log(email))
  .catch((error) => console.error(error));

Or if you prefer a resource sub-api directly:


const pkg = require('@clerk/clerk-sdk-node');
const { clients } = pkg;
 
clients
  .getClient(clientId)
  .then((client) => console.log(client))
  .catch((error) => console.error(error));

Setters

The following setters are available for you to change the options even after you've obtained a handle on a Clerk or sub-api instance:

If you have a Clerk handle:

clerk.secretKey = value;
clerk.serverApiUrl = value;
clerk.apiVersion = value;
clerk.httpOptions = value;

If are using a sub-api handle and wish to change options on the (implicit) singleton Clerk instance:

setClerkSecretKey(value)
setClerkServerApiUrl(value)
setClerkApiVersion(value)
setClerkHttpOptions(value)

Custom instantiation


import Clerk from '@clerk/clerk-sdk-node/esm/instance';
 
const clerk = new Clerk({ secretKey: 'secret_key' });
 
const clientList = await clerk.clients.getClientList();


const Clerk = require('@clerk/clerk-sdk-node/cjs/instance').default;
 
const clerk = new Clerk({ secretKey: 'secret_key' });
 
clerk.smsMessages
  .createSMSMessage({ message, phoneNumberId })
  .then((smsMessage) => console.log(smsMessage))
  .catch((error) => console.error(error));

Multi-session applications

If Clerk is running in multi-session mode, it's important to ensure your frontend sends the Session ID that is making the request.

Our middleware will look for a query string parameter named _clerk_session_id. If this parameter is not found, the middleware will instead choose the last active session, which may be subject to race conditions and should not be relied on for authenticating actions.

Connect/Express middlewares

The Clerk Node SDK offers two middlewares to authenticate your backend endpoints.

Manual authentication

Authenticate a particular session


import { sessions } from '@clerk/clerk-sdk-node';
import Cookies from 'cookies';
 
// Retrieve the particular session ID from a
// query string parameter
const sessionId = req.query._clerk_session_id;
 
// Note: Clerk stores the clientToken in a cookie 
// named "__session" for Firebase compatibility
const cookies = new Cookies(req, res);
const clientToken = cookies.get('__session');  
 
const session = await sessions.verifySession(sessionId, clientToken);

Authenticate the last active session

Using the last active session is appropriate when determining the user after a navigation.


import { clients, sessions } from '@clerk/clerk-sdk-node';
 
// Note: Clerk stores the clientToken in a cookie 
// named "__session" for Firebase compatibility
const cookies = new Cookies(req, res);
const clientToken = cookies.get('__session');  
 
const client = await clients.verifyClient(sessionToken);
const sessionId = client.lastActiveSessionId;
 
const session = await sessions.verifySession(sessionId, clientToken);