deduplicate-spotify-liked-songs-by-album.js

const fs = require("fs");
const path = require("path");

// open.spotify.com -> open devtools -> network requests -> find a request to grab your Bearer token
const TOKEN = "YOUR_TOKEN";

const fetchSpotify = async ({ endpoint, params, body, method = "GET" }) => {
  const baseurl = "https://api.spotify.com/v1/";
  const headers = {
    Authorization: `Bearer ${TOKEN}`,
    "Content-Type": "application/json",
    accept: "application/json",
  };

  const url = new URL(baseurl + endpoint);
  url.search = new URLSearchParams(params).toString();

  const request = new Request(url, {
    headers,
    body: body ? JSON.stringify(body) : undefined,
    method,
  });

  // log the request details
  console.log(method, request.url, body);

  const resp = await fetch(request);

  if (!resp.ok) {
    console.error(resp.status, resp.statusText);
    const text = await resp.text();
    throw new Error(text);
  }

  try {
    if (method === "DELETE") {
      console.log("skipping response for DELETE");
      return;
    }

    return await resp.json();
  } catch (e) {
    console.log("Failed to parse response");
    console.error(e);
    console.error(await resp.text());
  }
};

async function main() {
  const likedTracks = new Map();
  const duplicateTrackIds = [];

  let offset = 0;
  const limit = 20;

  let max = Infinity;
  let count = 0;

  while (true) {
    if (count >= max) {
      break;
    }

    count++;

    const tracks = await fetchSpotify({
      endpoint: "me/tracks",
      params: {
        offset,
        limit,
      },
    });

    if (tracks.items.length === 0) {
      break;
    }

    for (const item of tracks.items) {
      const track = item.track;
      const albumId = track.album.id;

      if (!likedTracks.has(albumId)) {
        likedTracks.set(albumId, track);
      } else {
        duplicateTrackIds.push(track.id);
      }
    }

    console.log("found duplicates", duplicateTrackIds.length, "tracks");

    offset += limit;
  }

  const deletePromises = [];
  // Now that we have all the duplicate track IDs, we can delete them in bulk
  for (let i = 0; i < duplicateTrackIds.length; i += 50) {
    const idsToDelete = duplicateTrackIds.slice(i, i + 50).join(",");

    deletePromises.push(
      fetchSpotify({
        endpoint: "me/tracks",
        params: {
          ids: idsToDelete,
        },
        method: "DELETE",
      })
    );
  }

  console.log("deleting", duplicateTrackIds.length, "tracks");

  await Promise.all(deletePromises);
}

main()
  .then(() => console.log("done"))
  .catch(console.error);