[async_hooks] stable API - tracking issue

[AndreasMadsen]

I posted requirements list for getting async_hooks into stable a while ago (nodejs/node#14717 (comment)). This is a very similar list.

Internal Technical

• Clarify breaking changes necessary for better performance (issue: Performance impact of async_hooks benchmarking#181)
  • Remove promise object from PromiseWrap (PR: async_hooks: remove promise object from resource node#23443)
  • Use a "MicrotaskWrap" instead of PromiseWrap (issue: Proposal for reworking promise integration into async_hooks #389)
• Setting up the benchmark suite to be run with and without async_hooks and see that there is only a small measurable difference given our tolerance.
• Deprecate runInAsyncIdScope (issue: Remove async_hooks runInAsyncIdScope API node#14328, PR: async_hooks: deprecate undocumented API node#16972)
• Deprecate setTriggerId (issue: Remove async_hooks setTrigger API node#14238, PR: async_hooks: deprecate undocumented API node#16972)
  • Implement internal replacement that we can optionally expose (PR: Refactor async_hooks initTriggerId node#17273)
• Deprecate Sensitive Embedder API (issue: Remove async_hooks Sensitive/low-level Embedder API node#15572, PR: async_hooks: deprecate undocumented API node#16972)
• Separate internal API from the external API (PR: async_hooks: deprecate undocumented API node#16972).
• Remove deprecated API (PR: async_hooks: remove deprecated API node#17147).
• Opt-out async_hooks state validation in v9.x. (PR: async_hooks: enable runtime checks by default node#16318)
• Make sure all nodecore uses of MakeCallback have an async_context.
• Integrate async_hooks into NAN (issue: Integrate C++ AsyncHooks Embedder API with native abstraction node#13254).
• Integrate async_hooks into n-api (issue: Integrate C++ AsyncHooks Embedder API with native abstraction node#13254).

Internal Non-Technical

• Specify whether a triggerAsyncId change will be a semver-major, semver-minor or semver-patch.
• Identify "tolerance level" of perf impact of async-hooks, especailly regarding promises.
• Is Async Hooks exposing the right logical model? (issue: How to deal with ambgious contexts for promise then callbacks #143)

External Non-Technical

• major APM vendor that uses async_hooks (N/Solid, New Relic, Elastic APM)
• npm modules with at least 5000 DL/month based on async_hooks (https://www.npmjs.com/package/trace & https://www.npmjs.com/package/cls-hooked)

After Stable

• Deprecate MakeCallback without async_context (PR: src: deprecate legacy node::MakeCallback node#18632)

[AndreasMadsen]

/cc @nodejs/async_hooks @nodejs/diagnostics

[AndreasMadsen]

/cc @jasnell who sometimes asks me about this

[refack]

@AndreasMadsen how about adding some external criteria, like TC39 uses or N-API (nodejs/node#14532)

1. major APM vendor that uses async_hooks (N/Solid)
2. npm modules with at least 5000 DL/month based on async_hooks (https://www.npmjs.com/package/trace & https://www.npmjs.com/package/cls-hooked)

[AndreasMadsen]

@refack added your 1. and 2. to the list. I'm not sure what you mean by TC39 uses. Regarding N-API I don't see why that should be a requirement. async_hooks has its own native Embedder API outside N-API, we can mark that as stable without N-API. In fact N-API shouldn't be marked stable before the async_hooks native Embedder API is marked stable since they depend on that. But async_hooks doesn't depend on N-API.

[refack]

Thanks. I just referenced TC39 and N-API as processes that use exit criteria that are independent of the development process, but take into account ecosystem adoption. So I agree that stability of N-API and async_hooks are independent (except for the embedder API)

[vdeturckheim]

FWIW, We plan to start using Async Hooks in Sqreen Agent in the upcomming weeks.

[hybrist]

Link by @watson for elastic: elastic/apm-agent-nodejs#77

[kjin]

PR to add async_hooks in Stackdriver Trace: googleapis/cloud-trace-nodejs#538

[AndreasMadsen]

Updated "Deprecate setTriggerId"

[AndreasMadsen]

Added:

• Clarify breaking changes necessary for better performance (issue: Performance impact of async_hooks benchmarking#181)