uap_mp.rb

#######
# Monkeypatch the user_agent_parser
#######

# Memoizes the pattern load because otherwise
# parsing user agents will read the file
# and build regex every time at the cost
# of 35ms

require "user_agent_parser"

module UserAgentParser
  class Parser
    def load_patterns(path)
      if defined?(@@_patterns)
        return @@_patterns
      end

      yml = YAML.load_file(path)

      # Parse all the regexs
      yml.each_pair do |type, patterns|
        patterns.each do |pattern|
          pattern["regex"] = Regexp.new(pattern["regex"])
        end
      end

      @@_patterns = [ yml["user_agent_parsers"], yml["os_parsers"], yml["device_parsers"] ]
    end
  end
end