How to persist custom challenge session

[agostbiro]

Hi,

I'm wondering what's the best solution to persisting the authentication challenge session across page loads. Consider the following scenario:

1. User goes to /login and requests login code
2. User retrieves login code from email
3. User reloads /login (or opens it in new tab)

The auth challenge session information is now lost and no info is stored by aws-amplify in local storage since the user is not authenticated yet.

[ottokruse]

That is not a trivial problem. A trick I've used is to store the session in Local Storage.

// Store session:
const session = (cognitoUser as any).Session;
localStorage.setItem('session', session);
localStorage.setItem('username', email);

// Then in another tab:
// Retrieve the stored session, and create the CognitoUser again, assigning the session:
const username = localStorage.getItem('username');
const session = localStorage.getItem('session');
const cognitoUser = new CognitoUser({ Username: username, Pool: userPool });
(cognitoUser as any).Session = session;

// Now you can continue the auth flow as you would before

That works across tabs--but not across browsers.

A cross browser solution would be more elaborate and would need to utilize storage elsewhere, where both browsers can access it.

[agostbiro]

Thanks! Same browser fits my requirements.

[agostbiro]

I've improved the persistence method a bit and posted a full snippet on SO:

https://stackoverflow.com/a/59613024/2650622

[mmeylan]

@ottokruse How do you get userPool when creating a new CognitoUser ?

[ottokruse]

Can be instantiated like this:

import { CognitoUserPool } from 'amazon-cognito-identity-js';
new CognitoUserPool({
    ClientId: environment.cognitoAppClientId,
    UserPoolId: environment.cognitoUserPoolId,
});

[ottokruse]

environment in my case Angular environment file