类:events.EventEmitterAsyncResource extends EventEmitter

\Class: events.EventEmitterAsyncResource extends EventEmitter

为需要手动异步跟踪的 EventEmitter 集成 EventEmitter 和 <AsyncResource>。具体来说,events.EventEmitterAsyncResource 实例触发的所有事件都将在其 异步上下文 中运行。

\Integrates EventEmitter with <AsyncResource> for EventEmitters that require manual async tracking. Specifically, all events emitted by instances of events.EventEmitterAsyncResource will run within its async context.

import { EventEmitterAsyncResource, EventEmitter } from 'node:events';
import { notStrictEqual, strictEqual } from 'node:assert';
import { executionAsyncId, triggerAsyncId } from 'node:async_hooks';
// Async tracking tooling will identify this as 'Q'.
const ee1 = new EventEmitterAsyncResource({ name: 'Q' });
// 'foo' listeners will run in the EventEmitters async context.
ee1.on('foo', () => {
 strictEqual(executionAsyncId(), ee1.asyncId);
 strictEqual(triggerAsyncId(), ee1.triggerAsyncId);
});
const ee2 = new EventEmitter();
// 'foo' listeners on ordinary EventEmitters that do not track async
// context, however, run in the same async context as the emit().
ee2.on('foo', () => {
 notStrictEqual(executionAsyncId(), ee2.asyncId);
 notStrictEqual(triggerAsyncId(), ee2.triggerAsyncId);
});
Promise.resolve().then(() => {
 ee1.emit('foo');
 ee2.emit('foo');
});const { EventEmitterAsyncResource, EventEmitter } = require('node:events');
const { notStrictEqual, strictEqual } = require('node:assert');
const { executionAsyncId, triggerAsyncId } = require('node:async_hooks');
// Async tracking tooling will identify this as 'Q'.
const ee1 = new EventEmitterAsyncResource({ name: 'Q' });
// 'foo' listeners will run in the EventEmitters async context.
ee1.on('foo', () => {
 strictEqual(executionAsyncId(), ee1.asyncId);
 strictEqual(triggerAsyncId(), ee1.triggerAsyncId);
});
const ee2 = new EventEmitter();
// 'foo' listeners on ordinary EventEmitters that do not track async
// context, however, run in the same async context as the emit().
ee2.on('foo', () => {
 notStrictEqual(executionAsyncId(), ee2.asyncId);
 notStrictEqual(triggerAsyncId(), ee2.triggerAsyncId);
});
Promise.resolve().then(() => {
 ee1.emit('foo');
 ee2.emit('foo');
});拷贝

EventEmitterAsyncResource 类具有与 EventEmitter 和 AsyncResource 本身相同的方法和选项。

\The EventEmitterAsyncResource class has the same methods and takes the same options as EventEmitter and AsyncResource themselves.