javascript - 如何使用 Node require 调用导入的异步函数？

Question

我正在尝试使用异步函数和 Puppeteer 获取纬度和经度数据。

我希望看到我获取的纬度和经度值。但是，我收到以下错误。

const latLong = await getLatLong(config);
                         ^^^^^

SyntaxError: await is only valid in async function

Node .js

const getLatLong = require('./util/latLong');
const latLong = await getLatLong(config);

经纬度.js

const getLatLong = async ( city, state, ) => {
  ...
  const browser = await puppeteer.launch();
  ...
  const page = await browser.newPage();
  await page.goto( url, waitUntilLoad, );
  await page.type( placeSelector, placeString, );
  await page.click( runButtonSelector, waitUntilLoad, );
  ...
  const results = await page.evaluate( ( lat, long, ) => {
    const latitude = Promise.resolve(document.querySelector(lat).value);
    const longitude = Promise.resolve(document.querySelector(long).value);
    const out = { latitude, longitude, }
    return out;
  }, [ latitudeSelector, longitudeSelector, ] );
  ...
  await browser.close();
  return results;
}

const latLong = async ({ city, state, }) => {
  const out = await getLatLong( city, state, );
  return out;
};

module.exports.latLong = latLong;

我做错了什么？

Answer 1

正如错误消息所示，await 只能在 async 函数中使用。将其包装在 async 中，例如如下所示:

const getLatLong = require('./util/latLong');

(async () => {
    const latLong = await getLatLong(config);
    console.log(latLong);
})();

但请记住，所有依赖于 latLong 结果的代码也必须位于 async 包装器中。