Javascript：异步函数返回未定义

Question

我正在使用Spotify API来获取给定类型的推荐。我已经编写了获取建议的函数（这是一个异步事件，因为它是从Spotify API中获取的）并返回它。当我通过将其合并到日志中来验证它时，我收到的值非常好，但是当我返回该值时，调用函数将收到“未定义”。在给定的代码中，在底部，我将返回“ body”，该主体将作为未定义返回。有人可以给我提示如何解决此问题吗？

  // List of viable genres to search, provided by Spotify API
  const genreObj = {
    genres: [
      "acoustic",
      "afrobeat",
      "alt-rock",
      "alternative",
      "ambient",
      "anime"
    ]
  };

  // Build string from inputs
  let genreString = "";
  for (let i = 0; i < genres.length - 1; i++) {
    if (genreObj.genres.includes(genres[i].toLowerCase())) {
      genreString += genres[i].toLowerCase() + "%2C";
    }
  }
  genreString += genres[genres.length - 1].toLowerCase();

  request.post(authOptions, async function(error, response, body) {
    if (!error && response.statusCode === 200) {
      // use the access token to access the Spotify Web API
      var token = body.access_token;
      var options = {
        url:
          "https://api.spotify.com/v1/recommendations?limit=10&market=US&seed_genres=" +
          genreString,
        headers: {
          Authorization: "Bearer " + token
        },
        json: true
      };
     request.get(options, async function(error, response, body) {
        console.log(body);
        return body;
      });
    }
  });
};