## Configure custom authorization logic with AWS Lambda

You can implement your own custom API authorization logic using an AWS Lambda function. To add a Lambda function as an authorization mode for your AppSync API, go to the **Settings** section of the **AppSync console**.

You will need to manage the details of token refreshes in your application code yourself. 

Here's how you can specify a function for handling token refresh when using Lambda as an authorization mode with DataStore:

```js
import { DataStore } from 'aws-amplify';

DataStore.configure({
  authProviders: {
    functionAuthProvider: async () => {
      const authToken = await refreshAuthToken(); // refreshAuthToken 
      
      return {
        token: authToken
      }
    },
  }
});
```