Wordpress-ios: SIWA: Login silently fails after SIWA succeeds

[astralbodies]

iOS 13.1b1
WP app 13.2.0.3.11
Login failed. Presented with “Do you want to sign into WP with this account?”, hit Continue, authorized with FaceID, then taken straight back to login screen.

p77Llu-czj-p2/#comment-14571

[astralbodies]

Second report with similar experience after enabling two-step auth on the existing wpcom account.

p77Llu-czj-p2/#comment-14576

[astralbodies]

More reports with wpcom two-factor breaking SIWA:

p77Llu-czj-p2/#comment-14593
p77Llu-czj-p2/#comment-14599

[rachelmcr]

Report related to attempting to sign up for a new account:

1. Had an account connected to Apple.
2. Changed wpcom account email and disconnected in Calypso, but didn't disconnect on the Apple side.
3. Attempted to log in again and it silently failed.

Ideally we could detect this case and present a message to the user explaining they need to disconnect on the Apple side to start over/create a new wpcom account.

p77Llu-czj-p2#comment-14578

[rachelmcr]

Report related to changing the account password:

1. Did SIWA on iOS to create account.
2. On the web, set an account password.
3. Logged out on iOS.
4. Attempted SIWA on iOS again and it silently failed.

p77Llu-czj-p2#comment-14615

[rachelmcr]

Another report with an unclear cause — this happened while trying SIWA with an Apple ID with an email address not associated with a WP.com account

p77Llu-czj-p2#comment-14618

[rachelmcr]

Another report, this time after pressing the home button instead of using Touch ID:

p77Llu-czj-p2#comment-14642

[Tug]

With regard to the login endpoint for mobile /users/social/new, it's designed to return an error for 2FA accounts: code='2FA_enabled', message='This account is associated with a WordPress.com account which has Two-Step Authentication enabled'
How do we handle this case for Google? It should probably be the same thing

[rachelmcr]

I can confirm that on an account with 2FA enabled, the error in the app logs is the one mentioned above:

Apple Authenticator: signup failed. error: Error Domain=WordPressKit.WordPressComRestApiError Code=7 "This account is associated with a WordPress.com account which has Two-Step Authentication enabled." UserInfo={WordPressComRestApiErrorMessageKey=This account is associated with a WordPress.com account which has Two-Step Authentication enabled., NSLocalizedDescription=This account is associated with a WordPress.com account which has Two-Step Authentication enabled., WordPressComRestApiErrorCodeKey=2FA_enabled}

However, it looks like we never handled this case for Google logins in the app. Trying to log in to an existing 2FA account with Google returns the same error (displayed in the UI to the user):

This account is associated with a WordPress.com account which has Two-Step Authentication enabled.

[ScoutHarris]

Error alert added with https://github.com/wordpress-mobile/WordPress-iOS/pull/12468.