doc: clarify socket and keepAliveTimeout interaction

[inversion]

doc: clarify socket and keepAliveTimeout interaction

Socket timeouts set using the connection event are replaced by
server.keepAliveTimeout when a response is handled.

Socket timeouts set in the connection event are replaced after a response is sent in the resOnFinish handler

server.on('connection', function(socket) {
  socket.setTimeout(60000);
});

In this case, the socket timeout is 60 seconds until a response is sent, at which point it becomes 5 seconds (the server.keepAliveTimeout default). This bit me when working with load balancers that maintain long-lived connections.

I have added a note to the connection event docs to the effect that is preferred to use server.keepAliveTimeout.

Checklist

• documentation is changed or added
• commit message follows commit guidelines

[mscdex]

The subsystem prefix in commit messages for doc-only changes should be doc instead of the specific core module name.

[Trott]

Suggested change

	If `socket.setTimeout()` is called here, note that the timeout will
	If `socket.setTimeout()` is called here, the timeout will

[vsemozhetbyt]

@Trott Are we landing as is or can we add this fix on landing?

[lpinca]

@inversion are you ok with @Trott suggestion? If so please accept it so this can land.
Thank you.

[Trott]

My change is non-blocking. It's not crucial that note that be removed. (It can also be removed by someone else who is landing this--just push to the branch. Or it can be removed in a subsequent PR as I imagine there are lots of opportunities for cleanup in the doc file.)

[Trott]

Hi, @inversion! Welcome and thanks for the pull request! Sorry to hear that this behavior caused you some grief!

/ping @nodejs/http to confirm that the behavior described here is correct and is currently undocumented.

/ping @nodejs/documentation Maybe there's a way to simplify or clarify the wording here a bit? Maybe a small piece of sample code with comments indicating the values and when they change? Or is that too much documentation real estate to describe what is likely an edge case?

[inversion]

The subsystem prefix in commit messages for doc-only changes should be doc instead of the specific core module name.

I'll fix this, probably worth adding it to https://github.com/nodejs/node/blob/master/doc/guides/contributing/pull-requests.md#commit-message-guidelines

[Trott]

I fixed up the commit message subsystem, rebased against master, and force-pushed.

Lite CI: https://ci.nodejs.org/job/node-test-pull-request-lite-pipeline/2423/

[inversion]

Thanks very much @Trott !

[Trott]

@nodejs/collaborators This could use another review.

[mcollina]

LGTM

[lpinca]

CI: https://ci.nodejs.org/job/node-test-pull-request-lite-pipeline/2545/

[lpinca]

Landed in 02601c2.