Newrelic Support

application_helper.rb

module ApplicationHelper
  ...
  
  def present(object, klass = nil)
    klass ||= "#{object.class}Presenter".constantize
    presenter = klass.new(object, self)
    yield presenter if block_given?
    presenter
  end
  
  ...
end

base_presenter.rb

require 'new_relic/agent/method_tracer'

class BasePresenter
  attr_reader :object, :template

  def initialize(object, template)
    @object = object
    @template = template
  end

  def self.presents(name)
    define_method(name) { object }
  end

  private
  def method_missing(method_name, *args, &block)
    template.send(method_name, *args, &block)
  end

  def respond_to_missing?(method_name, include_private = false)
    template.respond_to?(method_name, include_private) || super
  end

  add_method_tracer :initialize, 'BasePresenter/initialize'
  add_method_tracer :method_missing, 'BasePresenter/method_missing'
  add_method_tracer :respond_to_missing?, 'BasePresenter/respond_to_missing?'

  class << self
    include ::NewRelic::Agent::MethodTracer

    add_method_tracer :presents, 'BasePresenter/presents'
  end
end

note_presenter.rb

require 'new_relic/agent/method_tracer'

class NotePresenter < BasePresenter
  presents :note

  def recommend_button
    if user_signed_in? && current_user.is_editor?
      link_to "<i class='icon-plus'></i>", [:editor, note], class: "btn", target: "_blank"
    end
  end

  def pick_daily_button
    if user_signed_in? && [3, 16424, 24784].include?(current_user.id)
      link_to "<i class='icon-cloud-upload'></i>", new_editor_pick_daily_path(note_id: note.id), class: "btn", target: "_blank"
    end
  end

  def edit_button
    if user_signed_in? && note.authored_by?(current_user)
      link_to "<i class='icon-edit'></i>", note_edit_path(note), class: "btn"
    end
  end

  def add_collection_button
    if user_signed_in? && (note.authored_by?(current_user) || current_user.is_a_collection_editor?)
      "<a href='javascript:void(null)' class='btn add-collection' data-toggle='modal' data-target='#contribute-modal'><i class='icon-plus'></i><span>#{t('.add_to_collection')}</span></a>".html_safe
    end
  end

  def bookmark_button
    render "notes/bookmark_button", note: note if user_signed_in?
  end


  add_method_tracer :recommend_button, 'NotePresenter/recommend_button'
  add_method_tracer :pick_daily_button, 'NotePresenter/pick_daily_button'
  add_method_tracer :edit_button, 'NotePresenter/edit_button'
  add_method_tracer :add_collection_button, 'NotePresenter/add_collection_button'
  add_method_tracer :bookmark_button, 'NotePresenter/bookmark_button'
end

view.html.erb

<% present @note do |presenter| %>
  <div class="post-bg" id="flag">
    <div class="wrap-btn">
      <div class="btn-group editor-article">
          <span>
            <%= presenter.recommend_button %>
            <%= presenter.pick_daily_button %>
            <%= presenter.edit_button %>
            <%= presenter.add_collection_button %>
            <%= presenter.bookmark_button %>
          </span>
      </div>
    </div>
  </div>
<% end %>