[async_hooks] tracking issue

[AndreasMadsen]

Missing Handle context

• TCPwrap created from server (issue: AsyncWrap: TCPWrap created before MakeCallback node#2986, PR: async_wrap: correctly pass parent to init callback node#3216)
• HTTP sockets parserOnBody
  • issues: AsyncWrap: HTTP has no handle context node#3241, AsyncWrap: HTTP parserOnBody events happen outside pre/post node#4416
  • PR: http_parser: use MakeCallback node#5419 and src,http: fix uncaughtException miss in http node#5591, depends on: src: fix MakeCallback error handling node#4507
• Promises or Microtask in general
  • node issue: AsyncWrap promises#9
  • v8 issue: https://bugs.chromium.org/p/v8/issues/detail?id=4643
  • PR: async_wrap,src: promise hook integration node#13000
  • additional PRs: async_hooks: fix Promises with later enabled hooks node#13242, async_wrap,src: wrap promises directly node#13224
• nextTick (old issue: async-wrap: nextTick and setImmediate is ignored node#666, PR: Async Hooks - Initial Implementation node#12892)
• setTimeout, setInterval, setImmediate
  • old issue: async-wrap: nextTick and setImmediate is ignored node#666, Async Hooks - Initial Implementation node#12892
  • PR: Async Hooks - Initial Implementation node#12892
• exit and beforeExit has no context
  • ref: async_hooks: implement C++ embedder API node#13142 (review)
  • issue: none
  • PR: none
• emitDestroy doesn't emit destroy upon process termination (issue: Questions: async_hooks destroy callback vs setImmediate node#13262, PR: async_hooks: run destroy callbacks before normal exit node#13286)
• addon modules integration with AsyncWrap (EP: AsyncWrap public API proposal node-eps#18, PR: async_hooks: implement C++ embedder API node#13142)
• N-API addon modules integration with AsyncWrap (issue: Integrate C++ AsyncHooks Embedder API with native abstraction node#13254, PR: none)
• NAN-API addon modules integration with AsyncWrap (issue: Integrate C++ AsyncHooks Embedder API with native abstraction node#13254, PR: none)

More events

• onready (issue: async_wrap: when is callback ready to be called #11) - unlikely to be solved. As of now, not part of async_hooks API.
  • Some debate regarding promises: async_wrap,src: promise hook integration node#13000 (comment)
• onerror (issue: async-wrap: no way to catch errors without changing the throw origin node#669, async_wrap: error handling #7) - awaiting use cases. As of now, not part of async_hooks API.
• ondestructor (PR: AsyncWrap external API improvements node#3461)

API

• process.binding is being deprecated by node: deprecate public access to process.binding node#2768 (issue: missing, PR: Async Hooks - Initial Implementation node#12892)
• support multiple independent setupHooks calls. (issue: Multiple users of asyncWrap in a single application? #40, PR: Async Hooks - Initial Implementation node#12892)
• async wrap hook error handling (PR: Asyncwrap more node#5756)
• add exception throw flag to post hook (PR: Asyncwrap more node#5756)
• add parent handle to init callback (PR: async_wrap: correctly pass parent to init callback node#3216)
• add unique id (PR: AsyncWrap external API improvements node#3461)
• add unique id to all hooks: (PR: async_wrap: add uid argument to all asyncWrap hooks node#4600)
• unique ids should be a double, int32 is not enough. (PR: async_wrap: pass uid to JS as double node#7096)

Documentation

• intial documentation (PR: docs: add up to date documentation for AsyncWrap #27)
• document unique id (PR: Async wrap update - destroy hook and uid #37)
• document ondestructor (PR: Async wrap update - destroy hook and uid #37)
• document unique id on all hooks (PR: docs: update after nodejs/node#4600 #39)
• document public JS async_hooks API. (PR: docs: documenting async hooks features node#13287)
• document public C++ Embedder API – is the header file sufficient? (PR: none)

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If something is missing just edit this. But add a comment so we can keep the history.

[Qard]

Nice, thanks for putting this together! 😸

[AndreasMadsen]

Added:

• no good way for native modules to integrate with AsyncWrap (PR: async_wrap: make native API public node#3504)
• add unique id (PR: AsyncWrap external API improvements node#3461)

[AndreasMadsen]

@trevnorris could you add a link to the Promises issue in v8.

[trevnorris]

@AndreasMadsen Sorry. Forgot about this. Here's the link: https://bugs.chromium.org/p/v8/issues/detail?id=4643

[chrisdickinson]

Adding Noting nodejs/node#4416 here.

[AndreasMadsen]

updates:

work is being done on:

• HTTP sockets parserOnBody (PR: Fix async wrap http node#4509, depends on: src: fix MakeCallback error handling node#4507)

new:

• add unique id to all hooks: (PR: async_wrap: add uid argument to all asyncWrap hooks node#4600)

[trevnorris]

Note: Getting MakeCallback reentrant, which is necessary to fix some issue with AsyncWrap, has been a bit of a pain. Hopefully will be able to finish it this week.

[trevnorris]

MakeCallback is now reentrant, and working on a few other improvements for an EnterpriseJS talk today. I'll throw them up in a PR later this week.

[AndreasMadsen]

Updated with PR: nodejs/node#8531 and EP: nodejs/node-eps#18

The current status is that Promises and addon integration is still a todo. The Addon integration solution is documented in nodejs/node-eps#18, but not yet implemented.

[Jeff-Lewis]

"V8 promise hooks should ship with V8 5.7 and should be available in Node 8." - ofrobots

[joshgav]

@trevnorris can you share an update?

[bajtos]

IMHO, it would be great if async_hooks were calling V8Inspector::asyncTask* to notify the built-in inspector (debugger) about async boundaries, allowing the inspector to show long (async) stack traces in the UI. See nodejs/node#11370

[AndreasMadsen]

async_hooks have landed as an undocumented API. Documentation will be added soon, see: nodejs/node#12953

I have updated the tracking issue to reflect this.

[overlookmotel]

Great news! But does the fact that Promises/Microtask is not ticked off on OP indicate this isn't working yet?

[AndreasMadsen]

@overlookmotel Yes, Promises will come in another PR soon. It was excluded from nodejs/node#12953 because it was already quite big and we wanted to land it before we got more merge conflicts.

[mhdawson]

Added this

n-API addon modules integration with AsyncWrap (EP: nodejs/node-eps#18, PR: someone needs to be assigned).

as we need to cover both NaN and N-API

[matthewloring]

@overlookmotel Check out nodejs/node#13000

[AndreasMadsen]

The C++ Embedder API is in progress, added a PR reference: nodejs/node#13142

[AndreasMadsen]

updated promise support status and added: "exit and beforeExit has no context" which we will likely address post node v.8.x

[AndreasMadsen]

C++ Embedder API has been implemented and merged. I've created an issue for integrating it with NAN and N-API.

[AndreasMadsen]

Closing this issue. I will create a new one for how we are going to bring async_hooks into stable.