Handle failure in guest registration

[ashfame]

When a server doesn't have guest account registration enabled, it fails with this error.

It should show unknownRoomView with a login button

[psrpinto]

There's another error message than can be shown that is apparently also related to this:

null is not an object (evaluating 'this._session.isGuest')

[psrpinto]

I found another error message than seems to be related to this:

Something went wrong
Cannot read properties of null (reading 'isGuest')

Steps to reproduce:

1. Logout of all chatrix sessions
2. Go to the block editor and add a chatrix block
3. Change room in block inspector to #meta:community.wordpress.org
4. Error shows

[psrpinto]

I think this issue manifests itself differently according to whether the user has a session open or not, and also depends on if they have "previously-opened" sessions. That explains why there are different error messages.

I think we might need to rework how single-room mode is handled, specifically in what concerns the case where a previous session exists. In this code chosenSession is not defined, so that's surely part of the issue.

Here's all the use cases I could think of (can you think of any others?), and what I think the behaviour should be for each:

• [x] User has a session open -> Navigate to room view for configured roomIdOrAlias
• [x] User does not have a session open
  • [x] User has exactly one previously-opened session -> Open said session -> Navigate to room view for configured roomIdOrAlias
  • [x] User has many previously-opened sessions -> Navigate to session picker -> User selects a session -> Navigate to room view for configured roomIdOrAlias
  • [x] User has no previously-opened sessions
  • [x] Room is not world-readable, or homeserver has guest registration disabled -> Navigate to Login
  • [x] Room is world-readable -> Do guest login -> Navigate to room view for configured roomIdOrAlias

I think we should rework the code to implement this ^, I would be happy to do so.

[akirk]

Great. Please proceed on working on this, it's a blocker as we experienced in today's meeting.

[ashfame]

@psrpinto Can you elaborate on what you mean with "session open" here, as I don't understand this branching:

- User does not have a session open
    - User has exactly one previously-opened session

I would add another condition while doing guest login. When its a 403 (meaning guest registrations on server is disabled), we behave as if the room is not world-readable and navigate to login.

[psrpinto]

Good catch, I edited my comment to add the condition for when homeserver has guest registration disabled.

Can you elaborate on what you mean with "session open"

By "session open" I mean that the user went past the session picker and is "inside" a session, prior to loading chatrix in single-user mode. (The case where they have a single session is a special case of this, where the session picker isn't displayed, but from a code perspective it's the same, they are "inside" the session even if they don't see the session picker).

[psrpinto]

In addition, when I say "previously-opened", I mean they see the session picker with previously used sessions, but they aren't "inside" any session.

[ashfame]

Gotcha, thanks for explaining! The complete branching makes sense now & I think that covers everything 👍

[ashfame]

Related: https://github.com/Automattic/chatrix/issues/209