Use Aspector for stackoverflow question http://stackoverflow.com/questions/14396035/ruby-rails-prepend-append-code-to-all-methods

.rvmrc

rvm use 1.9.3@perf_aspect --create

perf_aspect.rb

class ApplicationController
end

class Products < ApplicationController
  # Action
  def action
    foo
    bar
  end

  # Other methods
  def foo
    caculation = 5 * 4
  end

  def bar
    caculation = 1 / 5
  end
end

##############################

class Perf
  def initialize
    @results = []
  end

  def log(note)
    @start = Time.now
    @note  = note
  end

  def write!
    if @results.find {|h| h[:note] == @note } # Update :sec method exists in results
      @results.select { |h| h["note"] == @note; h[":sec"] = (Time.now - @start).round(3) }
    else # Add new Hash to results
      @results << { :note => @note, :sec => (Time.now - @start).round(3) }
    end
  end

  def results
    content = "
    PERFORMANCE STATISTICS!
    "
    @results.each do |r|
      content += r[:note] + "   " + r[:sec].to_s + "
      "
    end
    content += "
    "
    #Rails.logger.info content
    puts content
  end
end

##############################

require 'aspector'

class PerfAspect < Aspector::Base

  # Change log level to DEBUG or TRACE to see how the aspect works
  #logger.level = Aspector::Logging::DEBUG

  around options[:action_methods] do |proxy|
    @perf ||= Perf.new
    proxy.call
    @perf.results
  end

  around options[:other_methods], :method_arg => true do |method, proxy, *args, &block|
    @perf.log(method)
    result = proxy.call *args, &block
    @perf.write!
    result
  end

  def self.apply_to target, action_methods, other_methods = nil
    other_methods ||= target.instance_methods(false) - action_methods
    apply(target, :action_methods => action_methods, :other_methods => other_methods)
  end
end

PerfAspect.apply_to(Products, [:action])

##############################

Products.new.action