Shower

Shower allows the creation of an unlimited number of event streams through a single connection! Server side events have never been easier and more efficient. Since there is no needed to persist a database connection, the amount of concurrent users is only limited by your Rails server.

Requirements

Multithreaded Server

As with any application wishing to use ActionController::Live, a multithreaded server is required. I recommend, Puma, it's open source and free. Passenger Enterprise is another option, it's a little simpler to setup then Puma.

Redis

A Redis server must be installed and running. Messages are pushed to a Redis server, where the Shower::StreamController then picks them up and pushes them to the event stream. Because of this, the event stream does not need a database connection!

Installation

Add this line to your application's Gemfile:

gem 'shower'

And then execute:

$ bundle

After bundling you need to run the initial installation generator for javascript client usage:

$ rails g shower:install

Configuration

Create config/initializers/redis.rb and configure Redis connection:

$redis = Redis.new(host: '127.0.0.1', port: 6379)

Usage

Publishing

Pushing messages to an event stream is simple, just pass the event name and the data. The data will be converted to JSON using to_json.

Shower::Stream.publish('message.new', { username: 'anon', message: 'hello!' })

Subscription

Subscribing to an event stream on server side.

Shower::Stream.subscribe(['message.new']) do |event, data| 
  # do something with event
  # do something with data
end

Listening

To listen for messages, use the JavaScript Shower class. The constructor takes the path and an array of events.

stream = new Shower('/stream', ['message.new', 'alert.new'])

Now define a callback for each event.

stream.addEventListener('message.new', (event) ->
  message = JSON.parse(event.data)
  console.log 'new message:'
  console.log message
)

stream.addEventListener('alert.new', (event) ->
  alert(event.data)
)

Contributing

1. Fork it ( https://github.com/[my-github-username]/rails_script/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request