过滤/恢复Promise.all结果

Question

例如:

function myFunc(args ...){
  ...
  return Promise.all(myPromisesArray)
}

如果内部的承诺myPromisesArray失败,我将只在返回值中得到拒绝原因.

有没有办法恢复所有其他已解决的值？

Answer 1

如果你正在使用Q,那么有一个叫做的函数Q.allSettled基本上就是你要求的.

否则,这个简单的函数会给你所有 promises 的结果,并告诉你是成功还是失败.然后,您可以对成功或失败的承诺做任何您需要做的事情.

/**
 * When every promise is resolved or rejected, resolve to an array of
 * objects
 *   { result: [ Promise result ], success: true / false }
**/
function allSettled(promises) {
  return Promise.all(
    promises.map(
      promise => promise.then(
        // resolved
        (result) => ({ result: result, success: true }),
        // rejected
        (result) => ({ result: result, success: false })
      )
    )
  );
}

// example usage:
const one = Promise.resolve(1);
const two = Promise.reject(2);
const three = Promise.resolve(3);

allSettled([ one, two, three ])
  .then((results) => {
    console.log(results[0]); // { result: 1, success: true }
    console.log(results[1]); // { result: 2, success: false }
    console.log(results[2]); // { result: 3, success: true }
  });