# identify

Learn how to identify users on the server side.

This function associates the current session with an identified user. It is the server-side equivalent of the client-side [`identify`](/reference/sdk/javascript/api/plug/identify) method.

Call this function when a user authenticates in your application to link their session with their user ID. The SDK issues a signed user token and sets the corresponding cookie.

## Signature

This function has the following signature:

```ts
function identify(userId: string): Promise<void>
```

## Example

Here is an example of how to use this function in a server API route:

**Identify example**

**JavaScript**

```js
export default defineEventHandler(async event => {
  const body = await readBody(event);

  // Your logic to authenticate the user
  const userId = await auth.login(body.email, body.password);

  if (userId !== null) {
    await identify(userId);
  }

  return {success: userId !== null};
})
```

**TypeScript**

```ts
export default defineEventHandler(async event => {
  const body = await readBody(event);

  // Your logic to authenticate the user
  const userId = await auth.login(body.email, body.password);

  if (userId !== null) {
    await identify(userId);
  }

  return {success: userId !== null};
})
```

## Parameters

- `userId`: `string`

  The user ID to associate with the current session.