Debugger failed to attach: handshake failed - connection prematurally closed

[olkornii]

[kind/bug]

What versions of software are you using?

• Operating System: Fedora 38
• IntelliJ version: 2023.2.4(Community Edition)
• Intellij-rsp extension version: 0.7.0.109

What did you run exactly?

Run WildFly30 with Debug.

Actual behavior

"Debugger failed to attach: handshake failed - connection prematurally closed" red text in output.

It seems to have no effect. Attempt to pause server in Debug tab -> open localhost:8080 -> loading... -> unpause server in Debug tab -> loaded.

Expected behavior

Any logs, error output, etc?

[robstryker]

In previous versions I would see it occasionally attempt to connect and get rejected via a failed handshake multiple times before finally successfully connecting.

I am not able to reproduce the issue right now, but, I have seen it before. After analyzing our own code, though, I can verify that we do poll on the debug port to see when it's ready before we go ahead and connect that debugger. We don't want to attempt to connect the debugger before the server is ready for it.

Either way, it appears to be our fault (polling and disconnecting the debug port), but the output is harmless and does not interfere with functioning of the project.