orta / slack-ruby-bot

The easiest way to write a Slack bot in Ruby.

Slack-Ruby-Bot

A generic Slack bot framework written in Ruby on top of slack-ruby-client. This library does all the heavy lifting, such as message parsing, so you can focus on implementing slack bot commands. It also attempts to itroduce the bare minimum number of requirements or any sorts of limitations. It's a Slack bot boilerplate.

Usage

A Minimal Bot

Gemfile

source 'http://rubygems.org'

gem 'slack-ruby-bot'

pongbot.rb

require 'slack-ruby-bot'

module PongBot
  class App < SlackRubyBot::App
  end

  class Ping < SlackRubyBot::Commands::Base
    command 'ping' do |client, data, _match|
      client.message text: 'pong', channel: data.channel
    end
  end
end

PongBot::App.instance.run

After registering the bot, run with SLACK_API_TOKEN=... bundle exec ruby pongbot.rb. Have the bot join a channel and send it a ping.

A Production Bot

A typical production Slack bot is a combination of a vanilla web server and a websocket application that talks to the Slack Real Time Messaging API. See our Writing a Production Bot tutorial for more information.

More Involved Examples

The following examples of production-grade bots based on slack-ruby-bot are listed in growing order of complexity.

• slack-mathbot: Slack integration with math.
• slack-google-bot: A Slack bot that searches Google, including CSE.
• slack-aws: Slack integration with Amazon Web Services.
• slack-gamebot: A generic game bot for ping-pong, chess, etc.

Commands and Operators

Bots are addressed by name and respond to commands and operators. By default a command class responds, case-insensitively, to its name. A class called Phone that inherits from SlackRubyBot::Commands::Base responds to phone and Phone and calls the call method when implemented.

class Phone < SlackRubyBot::Commands::Base
  command 'call'

  def self.call(client, data, _match)
    send_message client, data.channel, 'called'
  end
end

To respond to custom commands and to disable automatic class name matching, use the command keyword. The following command responds to call and 呼び出し (call in Japanese).

class Phone < SlackRubyBot::Commands::Base
  command 'call'
  command '呼び出し'

  def self.call(client, data, _match)
    send_message client, data.channel, 'called'
  end
end

You can combine multiple commands and use a block to implement them.

class Phone < SlackRubyBot::Commands::Base
  command 'call', '呼び出し' do |client, data, _match|
    send_message client, data.channel, 'called'
  end
end

Command match data includes match['bot'], match['command'] and match['expression']. The bot match always checks against the SlackRubyBot::Config.user and SlackRubyBot::Config.user_id values obtained when the bot starts.

Operators are 1-letter long and are similar to commands. They don't require addressing a bot nor separating an operator from its arguments. The following class responds to =2+2.

class Calculator < SlackRubyBot::Commands::Base
  operator '=' do |_data, _match|
    # implementation detail
  end
end

Operator match data includes match['operator'] and match['expression']. The bot match always checks against the SlackRubyBot::Config.user setting.

Bot Aliases

A bot will always respond to its name (eg. rubybot) and Slack ID (eg. @rubybot), but you can specify multiple aliases via the SLACK_RUBY_BOT_ALIASES environment variable or via an explicit configuration.

SLACK_RUBY_BOT_ALIASES=:pp: table-tennis

SlackRubyBot.configure do |config|
  config.aliases = [':pong:', 'pongbot']
end

This is particularly fun with emoji.

Bots also will respond to a direct message, with or without the bot name in the message itself.

Generic Routing

Commands and operators are generic versions of bot routes. You can respond to just about anything by defining a custom route.

class Weather < SlackRubyBot::Commands::Base
  match /^How is the weather in (?<location>\w*)\?$/ do |client, data, match|
    send_message client, data.channel, "The weather in #{match[:location]} is nice."
  end
end

SlackRubyBot::Commands::Base Functions

send_message(client, channel, text)

Send text using a RealTime client to a channel.

send_message_with_gif(client, channel, text, keyword)

Send text along with a random animated GIF based on a keyword.

send_gif(client, channel, keyword)

Send a random animated GIF based on a keyword.

Built-In Commands

Slack-ruby-bot comes with several built-in commands. You can re-define built-in commands, normally, as described above.

[bot name]

This is also known as the default command. Shows bot version and links.

[bot name] hi

Politely says 'hi' back.

[bot name] help

Get help.

Hooks

Hooks are event handlers and respond to Slack RTM API events, such as hello or message. You can implement your own by extending SlackRubyBot::Hooks::Base.

For example, the following hook handles user_change, an event sent when a team member updates their profile or data. This can be useful to update the local user cache when a user is renamed.

module MyBot
  module Hooks
    module UserChange
      extend SlackRubyBot::Hooks::Base

      def user_change(client, data)
        # data['user']['id'] contains the user ID
        # data['user']['name'] contains the new user name
        ...
      end
    end
  end
end

RSpec Shared Behaviors

Slack-ruby-bot ships with a number of shared RSpec behaviors that can be used in your RSpec tests. Require 'slack-ruby-bot/rspec' in your spec_helper.rb.

• behaves like a slack bot: A bot quacks like a Slack Ruby bot.
• respond with slack message: The bot responds with a message.
• respond with error: An exception is raised inside a bot command.

Contributing

See CONTRIBUTING.

Upgrading

See CHANGELOG for a history of changes and UPGRADING for how to upgrade to more recent versions.

Copyright and License

Copyright (c) 2015, Daniel Doubrovkine, Artsy and Contributors.

This project is licensed under the MIT License.