Authenticator is not redirecting user to login page after account verification code is entered

The issue you're experiencing with Amplify Gen 2 and Cognito, where the user is not automatically logged in after account verification, is a common challenge. By default, Cognito doesn't automatically redirect users to the login page or automatically log them in after account confirmation.

To address this, you have a few options:

1. Custom Lambda Trigger: You can implement a post-confirmation Lambda trigger. This trigger can be used to generate an access token for the user immediately after their account is confirmed. You would use the AdminInitiateAuth API within this Lambda function to generate the token, using the USER_PASSWORD_AUTH flow. This approach allows you to authenticate the user without requiring them to log in again manually.

2. Client-side Handling: On the client-side, you can detect when the account confirmation is successful and programmatically trigger the login process. This would involve listening for the confirmation event and then using Amplify's authentication methods to sign the user in.

3. Amplify Configuration: Ensure that your Amplify configuration is correctly set up. In your app.component.ts file, you should have:

   Amplify.configure(outputs);

   And in the constructor:

   constructor(public authenticator: AuthenticatorService) {
       Amplify.configure(outputs);
   }

   This configuration is crucial for the proper functioning of Amplify's authentication flow.

4. Custom Redirect: If you're using a custom confirmation flow, you could implement a redirect to your login page after successful confirmation. This would require setting up an API Gateway endpoint and a Lambda function to handle the confirmation and redirect process.

Remember, the goal is to create a seamless user experience while maintaining security. Whichever approach you choose, ensure that it aligns with your application's security requirements and user flow design.

If you're still facing issues after trying these approaches, you may want to review your Amplify and Cognito configurations to ensure all settings are correctly aligned with your desired authentication flow.

Sources
How can I issue an access token immediately after account confirmation in AWS Cognito without requiring the user to log in again? | AWS re:Post
Amplify gen 2, amplify-authenticator "There is already a signed in user." | AWS re:Post

Hi,

After user verification in Amplify Gen 2 with Cognito, if you want automatic login instead of returning to the create account tab, you have two main approaches:

1. Lambda Trigger Approach: Create a post-confirmation Lambda trigger in Cognito. This trigger will automatically generate authentication tokens after the user verifies their account, eliminating the need for manual login.

2. Client-side Approach: Handle the verification success on the client side and trigger automatic login. Here's a basic implementation:

import { Authenticator } from '@aws-amplify/ui-react';
import { Auth } from 'aws-amplify';

function App() {
  return (
    <Authenticator
      services={{
        async handleVerifyUser(params) {
          try {
            // Handle normal verification
            const result = await params.handleVerifyUser(params);
            
            // After verification, attempt auto-login
            if (result.username && params.password) {
              await Auth.signIn(result.username, params.password);
            }
            return result;
          } catch (error) {
            console.error('Verification error:', error);
            throw error;
          }
        }
      }}
    >
      {/* Your app content */}
    </Authenticator>
  );
}

The Lambda trigger approach is more secure but complex, while the client-side approach is simpler but requires temporary password storage. Choose based on your security requirements.

For implementation details, check:

• Cognito Post Confirmation Triggers