Community invite appears briefly, then shows error "failed to load"

[jryans]

Description

I received a community invite to +polynomial-supporters:matrix.org. When I click on it in the Riot's room list, the invite appears for ~2 secs, but it is then replaced with the error "Failed to load +polynomial-supporters:matrix.org".

In the console, I see:

Failed to get resource GroupMembers for +polynomial-supporters:matrix.org 
Object { errcode: "M_UNKNOWN", name: "M_UNKNOWN", message: "More than one row matched", data: {…}, httpStatus: 500, stack: "" }
GroupStore encountered error whilst fetching data for +polynomial-supporters:matrix.org 
Object { errcode: "M_UNKNOWN", name: "M_UNKNOWN", message: "More than one row matched", data: {…}, httpStatus: 500, stack: "" }

The failing requests seem to be:

GET https://matrix.org/_matrix/client/r0/groups/%2Bpolynomial-supporters%3Amatrix.org/users
[HTTP/2.0 500 Internal Server Error 942ms]
GET https://matrix.org/_matrix/client/r0/groups/%2Bpolynomial-supporters%3Amatrix.org/invited_users
[HTTP/2.0 403 Forbidden 131ms]

Most likely, this is related to matrix-org/synapse#2633. @benparsons suggested it could be possible for Riot ignore these errors and continue displaying the invite. I will investigate this approach.

I have sent debug logs for this issue as well.

Steps to reproduce

• Send a community invite... possibly twice according to Inviting a user to a group twice breaks the group matrix-org/synapse#2633 (I only received the invite once that I know of, so I am unsure)
• Attempt to view the invite in Riot

I expect to be able to view and accept the invite.

Version information

• Platform: web
• Browser: Firefox 65
• OS: macOS 10.13.6
• URL: riot.im/app

[turt2live]

This is because Riot is treating the 500 from /users request as a fatal error for the component (as it should - it can't reliably display the group otherwise). There was recently a patch to have the error returned from /invited_users work correctly, so that should not interfere with the page's ability to load.

[jryans]

There was recently a patch to have the error returned from /invited_users work correctly, so that should not interfere with the page's ability to load.

Assuming you mean the error handler in GroupStore, it did catch the 403 from /invited_users, but the 500 from /users is uncaught and triggers the "failed to load" message for the group. I'll experiment with also ignoring the extra error.

[jryans]

Fixed by matrix-org/matrix-react-sdk#2326.