• Version: v8.0.0
• Platform: All
• Subsystem: async_hooks, promises

Currently, there is no way (using async_hooks) to associate a PromiseReactionJob with the async id that fulfilled that promise. There is also no way to get the timing of the kResolved promise life cycle hook. These may be 2 separate issues, but are closely related.

Currently here is what is available for promises:

• init (Promise creation):
  • currentId: the async_id of the current execution context when the promise is created
  • triggerId: (once async_hooks: use parent promise as triggerId in init hook #13367 lands) The id of the parent promise
  • asyncId: an async id for the new promise
  • async_hooks.currentId(): same as currentId
  • async_hooks.triggerId(): trigger id for the current execution context (not the same as triggerId argument)
• before (start of PromiseReactionJob)
  • asyncId: an async id for the promise
  • async_hooks.currentId(): same as asyncId (once async_hooks.currentId() sometimes reports the wrong id during PromiseReactionJob #13427 is fixed)
  • `async_hooks.triggerId(): currently also affected by async_hooks.currentId() sometimes reports the wrong id during PromiseReactionJob #13427 (either parentPromise id or same as currentId?)
• after (end of PromiseReactionJob)
  • asyncId: an async id for the promise
  • async_hooks.currentId(): same as asyncId (once async_hooks.currentId() sometimes reports the wrong id during PromiseReactionJob #13427 is fixed)
  • async_hooks.triggerId(): currently also affected by async_hooks.currentId() sometimes reports the wrong id during PromiseReactionJob #13427 (either parentPromise id or same as currentId?)

Ideally there would be a way to access the id of the async context active during kResolved from the before/after hooks. Initially I had expected that during a PromiseReactionJob calling async_hooks.triggeredId() would return the contextId of the context responsible for resolving the promise. I am not sure if this is right approach. but having some way to link these 2 contexts is important for the apm use case.