Proposal: Making `AsyncLocalStorage` a global

[jasnell]

Adding new globals, especially non-standard ones, should always be carefully considered and weighed.

That said, I want to propose that we make AsyncLocalStorage a global in Node.js in order to better separate it conceptually from the async_hook API and generally just encourage it's use more.

@nodejs/tsc @nodejs/async_hooks @Qard @mcollina

[Qard]

Not sure about a global, but I did intentionally separate it from the async_hooks js files specifically with the intent that we could at least give it its own top-level file and leave async_hooks to re-export it, possibly with an eventual depreciation warning. Perhaps that would be a better route to take?

At the moment, I don't think I would block making it global, but I'm not sure I would support it either. I too feel a bit weird about making non-standard things global. 🤔

[mcollina]

I'm -1 of adding a global, but we should really move it out of async_hooks long term.

[legendecas]

I'd prefer to alias AsyncLocalStorage to a new built-in module out of async_hooks, instead of exposing it as a new global.

[Jamesernator]

That said, I want to propose that we make AsyncLocalStorage a global in Node.js in order to better separate it conceptually from the async_hook API and generally just encourage it's use more.

Making it global and then having AsyncContext ship later it would likely just be confusing as to which one should be used. Really I think AsyncLocalStorage should just be considered to be a stop-gap solution until AsyncContext (and the .enterWith-like proposal) are available.

[jasnell]

Ok. Thanks for the feedback. Will leave it as is for now.