process: deprecate _getActive* private APIs in favour of async_hooks

[RaisinTen]

The process._getActiveRequests() and process._getActiveHandles()
functions are not needed anymore because the async_hooks module
already provides functionality that helps us to keep a track of the
active resources.

Signed-off-by: Darshan Sen [email protected]

[aduh95]

We probably need a runtime deprecation first, right?

[RaisinTen]

@aduh95

We probably need a runtime deprecation first, right?

I wasn't sure about the deprecation process for private APIs but looking at #22011, I think so

EDIT: Done!

[mscdex]

Don't you need to set up various async hooks in advance to be able to achieve the same thing? Additionally as far as I'm aware, using async_hooks incurs overhead (even as soon as you require() it I believe) whereas the private APIs do not. Being able to probe what's keeping the event loop alive at any given moment (live) in production using these APIs is incredibly useful. If anything I think we should move towards making them "public" instead.

Also even though these functions are "private", I have a feeling this could cause a lot of breakage in the ecosystem.

[cjihrig]

I agree with @mscdex.

[jasnell]

I think we should leave the actual test in place since we're not removing these APIs yet.

[RaisinTen]

@mscdex

Don't you need to set up various async hooks in advance to be able to achieve the same thing? Additionally as far as I'm aware, using async_hooks incurs overhead (even as soon as you require() it I believe) whereas the private APIs do not. Being able to probe what's keeping the event loop alive at any given moment (live) in production using these APIs is incredibly useful.

Are you talking about the overhead incurred for this hook creation in particular or any require() call in general?

node/lib/async_hooks.js

Lines 258 to 266 in cf56abe

	const storageHook = createHook({
	init(asyncId, type, triggerAsyncId, resource) {
	const currentResource = executionAsyncResource();
	// Value of currentResource is always a non null object
	for (let i = 0; i < storageList.length; ++i) {
	storageList[i]._propagate(resource, currentResource);
	}
	}
	});

If ^, I think we can get rid of that one in #40810.

If anything I think we should move towards making them "public" instead.

Also even though these functions are "private", I have a feeling this could cause a lot of breakage in the ecosystem.

If we make it public, which exact module/object should we expose this from?

[RaisinTen]

Still too early to deprecate. There are some valid uses of the underlying handles that hasn't been addressed yet. (see #40813 (comment) for some uses in public GH repos)