example-rtm-client-datastore.js

var RtmClient = require('@slack/client').RtmClient;
var CLIENT_EVENTS = require('@slack/client').CLIENT_EVENTS;
var RTM_EVENTS = require('@slack/client').RTM_EVENTS;
var MemoryDataStore = require('@slack/client').MemoryDataStore;

var token = process.env.SLACK_API_TOKEN || '';

var rtm = new RtmClient(token, {
  logLevel: 'error', // check this out for more on logger: https://github.com/winstonjs/winston
  dataStore: new MemoryDataStore() // pass a new MemoryDataStore instance to cache information
});

rtm.start();

rtm.on(CLIENT_EVENTS.RTM.AUTHENTICATED, function handleRTMAuthenticated() {
  console.log('RTM client authenticated!');
});

rtm.on(RTM_EVENTS.MESSAGE, function handleRtmMessage(message) {
  console.log(
    'User %s posted a message in %s channel',
    rtm.dataStore.getUserById(message.user).name,
    rtm.dataStore.getChannelGroupOrDMById(message.channel).name
  );
});

rtm.on(RTM_EVENTS.REACTION_ADDED, function handleRtmReactionAdded(reaction) {
  console.log('Reaction added:', reaction);
});

rtm.on(RTM_EVENTS.REACTION_REMOVED, function handleRtmReactionRemoved(reaction) {
  console.log('Reaction removed:', reaction);
});