async_hooks.triggerAsyncId()

• 返回值：<number> 当前正在执行的回调函数所对应的资源 ID。

const server = net.createServer((conn) => {
  // The resource that caused (or triggered) this callback to be called
  // was that of the new connection. Thus the return value of triggerAsyncId()
  // is the asyncId of "conn".
  async_hooks.triggerAsyncId();

}).listen(port, () => {
  // Even though all callbacks passed to .listen() are wrapped in a nextTick()
  // the callback itself exists because the call to the server's .listen()
  // was made. So the return value would be the ID of the server.
  async_hooks.triggerAsyncId();
}); 拷贝

Promise 上下文默认可能无法获得有效的 triggerAsyncId。请参阅 承诺执行跟踪 部分。

【Promise contexts may not get valid triggerAsyncIds by default. See the section on promise execution tracking.】