等待循环直到在node.js中完成

Question

我制作了一个Twitter机器人，该机器人从reddit上获取帖子并定期发推文。我检查“是重复的帖子”控件，因此我将每个帖子写入.txt文件并逐行阅读。

我希望while循环等待直到完成（while（0））中断，但是我测试了我的代码，并且一直都发送相同的链接。但是while循环再次运行5-6次，然后继续进行并下载了重复的图片。

如何等待直到循环完全结束？

getImage: async function () {
var selectedSubreddit = await subreddit.randomSubreddit();
var imageURL;

//getting the image URL to download later
imageURL = await urlGetter(subreddit);

while (imageURL === '-1' || table.checkImage(imageURL[0]) === 1) {
  imageURL = await urlGetter(selectedSubreddit);
}

const downloadOptions = {
  url: imageURL[0],
  dest: `./images/x.jpg`
};

try {
  const { filename, image } = await downloader.image(downloadOptions);
  console.log('    -> Image downloaded!');
} catch (e) {
  console.log('    -> Image download failed');
  process.exit();
}
}

-urlGetter函数

const getURL = function (subreddit) {
   return new Promise((resolve, reject) => {
fetch(`https://www.reddit.com/r/${subreddit}/random.json?limit=1`)
  .then(res => res.json())
  .then(json => {
    let image;
    let oldImage;
    let crossParent;
    let permalink;

    try {
      image = json[0].data.children[0].data.url;
      crossParent = json[0].data.children[0].data.crosspost_parent;
      permalink = json[0].data.children[0].data.permalink;
      title = json[0].data.children[0].data.title;
    } catch (error) {
      image = json.data.children[0].data.url;
      crossParent = json.data.children[0].data.crosspost_parent;
      permalink = json[0].data.children[0].data.permalink;
      title = json[0].data.children[0].data.title;
    }

    if (!image) return resolve('-1');

    if (crossParent) return resolve('-1');

    let extension = image.substring(
      image.lastIndexOf('.') + 1,
      image.lastIndexOf('.') + 4
    );

    if (extension != 'jpg' && extension != 'png') return resolve('-1');

    return resolve([image, permalink, title]);
  })
  .catch(err => {
    return resolve('-1');
  });
  }); 
  };