Sending Messages

Blessed are those with a voice.

Okay, so you want to send messages, don't worry, we have you covered.

There are two main methods for sending messages, and two other for updating and deleting messages.

sendMessage

The main method to send a message is sendMessage:

// bot.sendMessage(channel, text, params);
bot.sendMessage('music-recommendation', 'Yeaaaaah!');
bot.sendMessage('joe', 'Hey Joe, how are you?');

bot.sendMessage('general', "I'm pretending to be Joe", { username: 'Joe' });

There are three arguments. channel – either name or ID of a channel/group/IM/user, whatever text – self-explanatory params – an object of options to get passed to Slack method chat.postMessage.

Normally, RTM API is used to send the message, unless you specify websocket: false in params. If you want to use the options of chat.postMessage, you must disable websocket.

You can also provide an array of channels to send to multiple channels at once.

An error is thrown if the specified channel is not found.

This method returns a promise which resolves to the message object.

sendAsUser

This method might look a little scary, and fun at the same time. Using this method you can send a message using a user's icon and username, pretending to be the user! Wait, what?! Don't worry, there is always a BOT tag near bot's name which indicates this message is sent using a bot, and not the user.

 bot.sendAsUser(user, channel, text, params);

The arguments are the same as sendMessage, except for user which is a username/id.

Example:

const Bot = require('slackbot-api');

const bot = new Bot({ token: 'YOUR_API_TOKEN' });
bot.listen(/Hello/i, message => {
  bot.sendAsUser(message.user, message.channel, 'Hahaha, I am a mirror!');
});

Updating and Deleting messages

Slack gives us the ability to update and delete our messages. Each message has a ts (short for timestamp), which is the identifier of messages.

Message instances also have update and delete methods for ease of use.

const msg = await bot.sendMessage('general', 'Hi');
bot.updateMessage('general', msg.ts, 'Hello!?');
bot.deleteMessage('general', msg.ts);

msg.update('Hello!?');
msg.delete();

Example:

'use strict';

const Bot = require('slackbot-api');

const bot = new Bot({ token: 'xoxb-40985785061-cHXNgAqKWILTfO4XfEmxuDVe' });
bot.listen(/Hello/i, async message => {
 let i = 5;
 const msg = await message.reply(i + '');

 const intv = setInterval(() => {
   msg.update(--i);

   if (i === 0) clearInterval(intv);
 }, 1000);
});

For more information, see Message Methods and Events.