Relax

Relax is a Ruby client/consumer library for relax – which is a multitenant message broker for Slack.

Installation

Add this line to your application's Gemfile:

gem 'relax-rb', require: 'relax'

And then execute:

$ bundle

Usage (with Rails)

Relax is meant to be used in conjunction with a web app such as Rails. There are two primary functions that this library lets you perform:

• Start Slack bots on Relax

• Listen for events generated by Relax.

Setup (Environment Variables)

The Relax Ruby client requires a few environment variables to be set up (these same environment variables are also used to set up the relax message broker).

RELAX_BOTS_KEY: This can be any string value and is used to store state about all Slack clients currently controlled by Relax in Redis. (Used by Relax::Bot)

RELAX_BOTS_PUBSUB: This can be any string value and is used to notify Relax brokers that a new Slack bot has been started. (Used by Relax::Bot)

RELAX_EVENTS_QUEUE: This can be any string value and is used by Relax brokers to send events to the client. (Used by Relax::EventListener)

For a full list of events that are sent from Relax brokers, visit the Relax Github page.

Starting Bots

To start a bot, or update a bot with a new token, call Relax::Bot.start!(team_uid, token) where team_uid is the UID of the team (generated by the Slack API) and token is the API token for the bot (again generated by the Slack API).

If a token is invalid or a bot connection is unsuccesful, you will receive a disable_bot event.

Listening for Events

Events are queued in Redis by Relax brokers in the REDIS_EVENTS_QUEUE key and Relax::EventListener.listen! listens for events and invokes the callback that is set by Relax::EventListener.callback=.

Setting the callback

The recommended way to set the callback method for events in Rails is an initializer, for e.g. in a file config/initializers/relax.rb:

callback = Proc.new do |event|
  Rails.logger.info "received event: #{event}"
  # handle event
end

Relax::EventListener.callback = callback

The callback can also be a class (or instance) method, in which case you should do something like this:

class RelaxEventHandler
  def self.handle_event(event)
    Rails.logger.info "received event: #{event}"
    # handle event
  end
end

Relax::EventListener.callback = RelaxEventHandler.method(:handle_event)

Starting the Listener

The recommended way to start the listener in a Rails app is to use Foreman. In your Procfile, create an entry like this:

relax: bundle exec rake relax:listen_for_events

And this will invoke Relax::EventListener.listen! as part your of your Rails application.

This process can be scaled indepedently from the rest of your web application, and so the more events you get, the more "relax" listener processes you can have.

Events

An Event is an instance of the [Relax::Event](https://github.com/zerobotlabs/relax-rb/blob/master/lib/relax/event.rb) class.

Read more about the different types of events generated by Relax here

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/zerobotlabs/relax-rb. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.