node.js - NodeJS : How to await an asynchronous script called by runInNewContext?

Question

我正在尝试执行自定义 Script对象使用 runInNewContext .

let myScript = (async () => {
  let response = await fetch('/article/promise-chaining/user.json');
  let user = await response.json();
})();

let vm = new Script(myScript, myScriptOptions);

let result = vm.runInNewContext(mySandbox, myContextOptions);
console.log("Done running!");

但是，我遇到的问题是我希望 runInNewContext 实际上等待 myScript 的异步函数完成运行。换句话说，我想要“跑完!”获取响应后打印。 这可能吗？请问我怎样才能实现它？

Answer 1

您必须:

1. 让您的原始函数返回一个 promise
2. 调用 runInNewContext 时等待该 promise 。

因此，假设您要返回用户对象:

let myScript = (async () => {
  let response = await fetch('/article/promise-chaining/user.json');
  let user = await response.json();
  return user;
})();

然后，在这里添加await

let result = await vm.runInNewContext(mySandbox, myContextOptions);

就好像您尝试打印结果的值一样，这将是一个 promise 所以添加等待将实现您想要实现的目标