Fnordmetric helper

summary.md

Goal

The point is to write a Fnordmetric helper. Fnordmetric is a "statsd-like" metric collector without the Carbon hassle.

Examples

• I would like to be able to do things like :

  push_timer :hell_yeah
    # do some code
  pop_timer

=> pop_timer pops the last timer pushed and sends an event to Fnormetric with the id hell_yeah. Thus, timers can be nested :

  push_timer :hell_yeah
    # do some code
    push_timer :some_nested_timer
    # some more code
    pop_timer
  pop_timer

=> this will send two events (:some_nested_timer first, then :hell_yeah)

• Other uses could be :

  times(:some_id) do
    # some code block
  end

=> this uses {push,pop}_timer behind the scenes

• Also, another style :

  class Users < Controller
    helper ::fnordmetric
    clock :login

=> this measure the login method execution time, by wrapping it automatically between push_timer/pop_timer calls

• Another usage, implemented in before/after blocks, to measuse several methods :

    before_all do |m|
      push_timer :performance, :this => "some args", :method => m
    end

    after_all do |m|
      pop_timer
    end

Problem

I basically tryied implementing all of this, and it always break when redirect* is called.

usage_example.rb

class Users < Controller
  helper ::fnordmetric

  before_all do |m|
    push_timer :performance, :this => "some args", :method => m
  end

  after_all do |m|
    pop_timer
  end

  def login
    redirect_referer if logged_in?
    return unless request.post?

    times :user_login_performance do 
      user_login(request.subset(:email, :password))
    end
    # do whatever now
  end
end