Sets the grouping field of an iTunes/Music selection with artist MusicBrainz tags via Node.js with a couple of OSA calls

add-grouping.js

const osa = require('osa2');
const fetch = require('node-fetch');
const cliProgress = require('cli-progress');

// Return a list of unique artists based on the selection
const fetchArtists = osa(() =>
  (Application('iTunes') || Application('Music'))
    .selection()
    .map((x) => x.artist())
    .filter((v, i, a) => a.indexOf(v) === i),
);

// Update the grouping tag for the artist
const setGrouping = osa((artist, tags) => {
  const songs = (Application('iTunes') || Application('Music')).playlists
    .whose({ name: 'Library' })[0]
    .tracks.whose({ artist: { _equals: artist } });

  for (const song of Array(songs)) {
    song.grouping.set(tags);
  }
});

// Return the tags for an artist or throw an error
const fetchTags = (artist) =>
  new Promise((resolve, reject) => {
    (async () => {
      try {
        const response = await fetch(
          `http://musicbrainz.org/ws/2/artist/?fmt=json&query=artist:${encodeURIComponent(artist)}`,
        );
        if (response.status !== 200) {
          throw new Error(`HTTP resonse ${response.status}`);
        }
        const data = await response.json();
        resolve(
          data.artists[0].tags
            .filter((t) => t.count > 0)
            .map((t) => t.name)
            .join(', '),
        );
      } catch (e) {
        if (e.message.match(/'filter'/)) {
          reject('Artist not found');
        } else if (e.message.match(/'tags'/)) {
          reject('Tags not found');
        }
        reject(e.message);
      }
    })();
  });

// Ensure each interation happens no more than once every 1000ms
const rateLimitCheck = async () => {
  if (!this.lastRequestTime) {
    this.lastRequestTime = 0;
  }

  const timeDiff = Date.now() - this.lastRequestTime;
  if (timeDiff < 1000) {
    await new Promise((r) => setTimeout(r, 1000 - timeDiff));
  }

  this.lastRequestTime = Date.now();
};

// Main function
(async () => {
  const artists = await fetchArtists();

  const missingArtists = [];
  const bar1 = new cliProgress.SingleBar({ stopOnComplete: true }, cliProgress.Presets.shades_classic);
  bar1.start(artists.length, 0);

  for (const artist of artists) {
    await rateLimitCheck();

    try {
      const tags = await fetchTags(artist);
      await setGrouping(artist, tags);
    } catch (error) {
      missingArtists.push([artist, error.message ?? error]);
      continue;
    } finally {
      bar1.increment();
    }
  }

  console.table(missingArtists);
})();