javascript - NodeJS 获取 promise 回调挂起

Question

我有这个代码:

fetch(url).then(response => {
  const json = response.json();
  console.log('simplest possible fetch', json, json.where);
});

在控制台中我得到:

simplest possible fetch Promise {[[PromiseStatus]]: "pending", [[PromiseValue]]: undefined} undefined

我大多数都得到了这个。有时我会获得“成功”状态。对我来说，这意味着回调正在 fetch promise 解决之前运行。

我希望函数仅在提取完成时运行。我该怎么做？

Answer 1

response.json() 返回一个promise，使用then 回调获取数据:

The json() method of the Body mixin takes a Response stream and reads it to completion. It returns a promise that resolves with the result of parsing the body text as JSON.

fetch(url)
  .then(response => response.json())
  .then(data => console.log('simplest possible fetch', data, data.where));