javascript - Console.log 作为 HTTP 请求发生在 Promise 数组中

Question

我正在向 API 发出一个 HTTP 请求，以获取数组上的尽可能多的条目。

我想要做的是 console.log 每次都在做一个请求，但我无法在它发生时记录它，它会等待所有的完成，然后它一次记录它。

const data = ['one','two']
    
// This simulates the API response I have no control here
const mockAPI = (timeout) => {
  return new Promise((resolve, reject) => setTimeout(() => resolve(), timeout))
}

let counter = 0

// For each entry in the array
const promises = data.map(() => {
  return new Promise(async (resolve, reject) => {
    // Keep track of how many request are we up to
    counter++
    // Log it
    console.log(counter)
    // Make the call to the API
    await mockAPI(3000)
    // Do something with the data from API...
    resolve()
  })
})
// I collect the results of all promises to processes it later on
const result = Promise.all(promises) 

我想要的是记录：

1

等待三秒钟 - 显然，只要 API 需要然后：

2

Answer 1

对每个请求和 console.log尝试使用for loop,await当你使用 时Promise.All，所有 fetches/async 任务并行运行（基于浏览器资源）

更新：增加了累积结果的方式

// This simulates the API response I have no control here
const mockAPI = (timeout) => {
  const rand = Math.floor(Math.random() * 100);
  return new Promise((resolve, reject) =>
    setTimeout(() => resolve(rand), timeout)
  );
};

(async function () {
  const results = [];
  let counter = 0;
  for (let i = 0; i < 3; i++) {
    console.log(counter++);
    const res = await mockAPI(3000);
    results.push(res);
  }

  console.log(results);
})();