尝试在异步函数中抛出错误时未处理的承诺拒绝

Question

我正在实现一段代码，该代码通过项目的构建并检查是否有多个带有featured: true 的页面。如果是这种情况，我想抛出一个错误，这样管道中的qa 作业就会失败。一切都会很好，但我得到了：

UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch()

这是我的代码：

/* eslint-disable no-restricted-syntax */
const fs = require('fs');
const findInDir = require('./utils/findInDir');

(async () => {
  const dir = './public/page-data/blog';
  const fileRegex = /.*/;
  const allFiles = findInDir(dir, fileRegex);
  let result = 0;

  for (const file of allFiles) {
    try {
      // eslint-disable-next-line no-await-in-loop
      const data = await fs.promises.readFile(file);
      const obj = JSON.parse(data);

      if (obj.result.pageContext.featured === true) {
        result += 1;
      }
    } catch (err) {
      // noop
    }
  }

  if (result > 1) {
    throw new Error('There are multiple featured blog posts, please fix.');
  }
})();

如何在异步函数中抛出错误？

Answer 1

您可以使用 catch 块来处理错误，如下所示：-

/* eslint-disable no-restricted-syntax */
const fs = require('fs');
const findInDir = require('./utils/findInDir');

(async () => {
  const dir = './public/page-data/blog';
  const fileRegex = /.*/;
  const allFiles = findInDir(dir, fileRegex);
  let result = 0;

  for (const file of allFiles) {
    try {
      // eslint-disable-next-line no-await-in-loop
      const data = await fs.promises.readFile(file);
      const obj = JSON.parse(data);

      if (obj.result.pageContext.featured === true) {
        result += 1;
      }
    } catch (err) {
      // noop
    }
  }

  if (result > 1) {
    throw new Error('There are multiple featured blog posts, please fix.');
  }
})().catch((e) => {
    console.log(e);
});