GUI2 times out connecting to Language Server on large projects

[somebody1234]

Repro steps

1. Create a new project from "Colorado COVID" template on the Cloud backend
2. Wait for the project to open

Expected result

No errors

Actual result

Connecting to Language Server times out

Details

Console logs:
localhost-1709807376658.log

WebSocket messages:
Note that the first reply from the backend arrives 17 (!) seconds after the request. This is higher than the 15 second limit, which is demonstrated by the second request being sent after roughly 16 seconds.

Console logs (screenshots):

[farmaazon]

I think the timeout itself is not much a problem; but the retry should properly interpret the 6002 error, and assume that the protocol is initialized.

There is however a problem here, namely that we need to know the response of initProtocol, because this is the only source of content roots. We could make sure we handle every response of initProtocol, even if it's for timed out request, but I'm not sure if libraries we use allows that.

I think the proper solution is to add an endpoint to language server file/roots allowing us to ask for them if needed. @4e6 are you able to add one?

[farmaazon]

Refinement notes:

• For now, let's increase the timeout. We can check if it's possible to retrieve proper response on 6002 error.
• Estimate includes possible unit tests for handling the error code, what may require slight refactoring.

[4e6]

@farmaazon errors can have a payload field with arbitrary JSON. We can even send the context roots with the 6002 Session already initialised error. Adding the file/roots endpoint is also possible

[enso-bot]

Adam Obuchowicz reports a new STANDUP for yesterday (2024-07-18):

Progress: Returned for a while to my modification of LS protocol, allowing us to recover from "already initialized" error. Improved solution a bit, fixed tests and documentation. the PR is ready to review; also started the next task of improving look of multiselect drop-down. It should be finished by 2024-07-22.

Next Day: Next day I will be working on the #9617 task. Finish new task