I. Using the Analytical Gem

If you are installing Kissmetrics in your Rails app, the JavaScript Library may actually be more appropriate for your frontend tracking. Consider using the Analytical RubyGem to help ease integration of multiple analytics products into your Rails app.

RubyGem link: http://rubygems.org/gems/analytical
GitHub link: https://github.com/jkrall/analytical

II. Another Rails Integration

This is an example on how to integrate Kissmetrics into a Ruby on Rails application using the basic Ruby Library.

Begin by placing the Ruby Library script in your lib/ directoy.
In the controller you wish to use, create a before_filter
Identify the user you want to track
Record your events and properties
That’s it! Let’s look at each individual step in more detail.

Step 1 - Install the library

Simply place the km.rb file you downloaded in to your lib/ directory. Copying the script in your lib/ directory allows Rails to source the Kissmetrics code. There is no need to require anything.

Step 2 - Create the before_filter

Initialize Kissmetrics before making any requests by calling KM.init. You can include this in a Rails initializer, or create a before_filter:

before_filter:km_init

def km_init
	KM.init(
  	'YOUR_API_KEY',
    :log_dir = File.join(RAILS_ROOT, 'log', 'km')
  )
end

Step 3 - Identify the user you want to track

There are two types of users to track here. You can track identified users, or unidentified users. The Ruby Library, unlike the JavaScript Library does not automatically provide a way to track anonymous/unidentified users. However, we often would like to track anonymous users, and then later after they have logged in, or better yet, signed up, continue keeping track of them. The following is an example how you can, through cookies, and KM.alias continue keeping track of such users.

before_filter:km_init

def generate_identifier
  now = Time.now.to_i
  Digest::MD5.hexidigest(
    (request.referrer || '') + rand(now).to_s +
     now.to_s + 
    (request.user_agent || '')
  )
end

def km_init
  KM.init(
  	'YOUR_API_KEY',
    :log_dir = File.join(RAILS_ROOT, 'log', 'km')
  )
  
  if not identity = cookies[:km_identity]
    identity = generate_identifier
    cookies[:km_identity] = {
      :value => identity,
      :expires => 5.years.from_now
    }
	end
  
  # This example assumes you have a current_user, with a property "email". Use whatever makes sense for you app.
  
  if current_user
    if not cookies[:km_aliased]
      KM.alias(identity, current_user.email)
      cookies[:km_identity] = {
        :value => true,
      	:expires => 5.years.from_now
    	}
    end
    KM.identify(identity)
  end
end

Step 4 - Record your events and properties

You can refer back to the Ruby Library for example API calls.