gistfile1.rbx

require 'net/http'

class GoogleAnalytics
  BASE_URL = "http://www.google-analytics.com/__utm.gif?"
  
  def self.create_url(request, options)
    params = {}
    raise(ArgumentError, "Can't create GA URL without an urchin code") unless params[:utmac] = options.delete(:ga_code)
    raise(ArgumentError, "Can't create GA URL without a page URI") unless params[:utmp] = options.delete(:page_uri)
    utmdt = options.delete(:description) || "-"    # page description
    params[:utmdt] = CGI.escape(utmdt)
    params[:utmhn] = request.host                           # domain request is served from
    params[:utmr] = request.env['HTTP_REFERER'] || "-"      # referring URL
    params[:utmv] = "4.3"                                   # tracking code version
    params[:utml] = "en-us"                                 # browser language (or could be pulled from user-agent)
    params[:utmsc] = "UTF-8"                                # language encoding (or could be pulled from user-agent)
    params[:utmsc] = options.delete(:color_depth) || "-"    # browser screen color depth
    params[:utmsr] = options.delete(:resolution) || "-"     # browser screen resolution
    java_enabled = options.delete(:java_enabled)
    params[:utmje] = java_enabled ? "1" : "0"               # browser supports java
    params[:utmfl] = options.delete(:flash_version) || "-"  # Flash version
    params[:utmn] = rand(8999999999) + 1000000000           # random request number
    params[:utmhid] = rand(8999999999) + 1000000000         # random request number
    params[:utmcn] = 1                                      # start new campaign session
    user_id = options[:user_id] ? 1000000000 + options.delete(:user_id).to_i : rand(8999999999) + 1000000000
    random_utma = rand(1147483647) + 1000000000             # random number for utma
    time = Time.now.to_i
    utmcc = "__utma=#{user_id}.#{random_utma}.#{time}.#{time}.#{time}.1;+__utmz=#{user_id}.#{time}.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none);"
    (utmcc += "+__utmv=#{user_id}." + options.map{|k,v| "#{k}=#{v}"}.join("+") + ";") unless options.empty?
    params[:utmcc] = CGI.escape(utmcc)
    url = BASE_URL + params.map{|k,v| "#{k}=#{v}"}.join("&")
    headers = {
      'Accept-language' => request.env['HTTP_ACCEPT_LANGUAGE'],
      'User-agent' => request.env['HTTP_USER_AGENT']
    }
    {:url => url, :headers => headers}
  end
  
  def self.call(request, options = {})
    ga_url = GoogleAnalytics.create_url(request, options)
    if RAILS_ENV == 'production'
      begin
        url = URI.parse(ga_url[:url])
        Net::HTTP.start(url.host, url.port) do |http|
          http.get("#{url.path}?#{url.query}", ga_url[:headers])
        end
      rescue
      end
    end
    ga_url
  end
end