Environment

Node: v20.11.1
H3: v1.11.1

Reproduction

https://github.com/joshmossas/h3-sse-on-closed-bug

Describe the bug

Calling eventStream.onClosed() in the current implementation registers a callback on both event.node.res.on('close') and writer.closed. This means that the callback will always fire twice, which could lead to some unexpected side effects, esp if users are interacting with things like database connections.

Additional context

We are already listening for event.node.res.on('close') by default (when autoclose is set to true). So, I propose we remove event.node.res.on('close') from the onClosed method because that case is already being handled in the default configuration.

I think if someone has chosen to set autoclose to false, they have already decided to take on additional work when it comes to cleanup. They can still manually register a callback on event.node.res.on('close') if they want.

Logs

No response