Slack archived channels delete

package.json

{
  "dependencies": {
    "request-promise": "4.2.2",
    "request": "2.83.0",
    "promise-seq": "2.0.1"
  }
}

slack-cleanup.js

// Notice: SLACK_TOKEN must be a 'xoxs' special token you can get while deleting a channel from the Web app with Chrome Network tools open. A regular token won't do.
var token = process.env.SLACK_TOKEN;

var request_promise = require("request-promise");
var promise_sequential = require("promise-seq").default;

// Tune this to avoid being rate-limited
var wait_delete = 10000;

// The Slack max. per request is 1000 so no need to change that
var list_limit = 1000;

console.log("NOTICE: THIS SCRIPT HAS A HARD-CAP OF 1000 CHANNELS PER RUN, RE-LAUNCH AS MANY TIMES AS NEEDED FOR FULL CLEANUP IF YOU HAVE MORE THAN 1000 ARCHIVED CHANNELS TO CLEAN.");

function process_chunk(fn_done, fn_error) {
  var chunk_size = 0;

  request_promise({
    method : "GET",
    url    : "https://slack.com/api/conversations.list",

    qs     : {
      token : token,
      limit : list_limit
    },

    json   : true
  })
    .then(function(conversations) {
      if (!conversations || conversations.ok !== true) {
        return Promise.reject(conversations.error);
      }

      chunk_size = conversations.channels.length;

      console.log("Listed conversations", chunk_size);

      // Filter on archived channels
      var channels = conversations.channels.filter(function(channel) {
        return channel.is_archived === true;
      });

      console.log("Filtered conversations", channels.length);

      // Sequential removal of match
      return promise_sequential(
        channels.map(function(channel, index) {
          return function() {
            return Promise.resolve()
              .then(function() {
                console.log("Will delete channel", channel.name);

                return new Promise(function(resolve) {
                  setTimeout(resolve, wait_delete);
                });
              })
              .then(function() {
                return request_promise({
                  method : "POST",
                  url    : "https://slack.com/api/conversations.delete",

                  qs     : {
                    token   : token,
                    channel : channel.id
                  },

                  json   : true
                });
              })
              .then(function(result) {
                if (!result || result.ok !== true) {
                  return Promise.reject(result.error);
                }

                console.log("Deleted channel", channel.name);
                console.log("Remaining:", channels.length - (index + 1));

                return Promise.resolve();
              })
              .catch(function(error) {
                console.error("Failed deleting channel", channel.name);

                return Promise.reject(error);
              });
          };
        })
      );
    })
    .then(function() {
      console.info("Chunk done");

      fn_done(chunk_size);
    })
    .catch(function(error) {
      console.error("error", error);

      fn_error();
    });
}

function schedule_next_chunk() {
  process_chunk(
    function(chunk_size) {
      if (chunk_size >= list_limit) {
        console.info("Chunk done, processing next");

        schedule_next_chunk();
      } else {
        console.info("Chunk done, no next chunk");

        process.exit(0);
      }
    },

    function() {
      console.error("Chunk processing aborted because of an error");

      process.exit(1);
    }
  );
}

// Schedule chunks processing
schedule_next_chunk();