ActionTracer

Log Rails application actions and filters when accepts a request.

Add this line to your application's Gemfile:

gem 'action_tracer', group: [:development, :test]

Notice this gem is for Rails with ApplicationController inherited ActiveController::Base.
Support for Rails application with ActiveController::API is comming soon.

Run rails server or run rspec and check log/action_tracer.log.

For example, you have a simple awesome_controller.rb like this:

class AwesomeController < ApplicationController
  before_action :require_login
  before_action :set_awesome, only: :show
  around_action :with_readonly
  after_action :store_location
  
  def index
   # ...
  end

  def show
    # ...
  end

private

  def require_login
    # ...
  end

  def with_readonly
    # ...
    yield
    # ...
  end

  def store_location
    # ...
  end
end

When you run rails server and access /awesome (action is #index),
it will put logs for log/action_tracer.log like this:

I, [2020-09-27T03:25:43.018298 #1]  INFO -- : ["APPLIED", :set_turbolinks_location_header_from_session, "/usr/local/bundle/gems/turbolinks-5.2.1/lib/turbolinks/redirection.rb", 43]
I, [2020-09-27T03:25:43.019410 #1]  INFO -- : ["APPLIED", :verify_authenticity_token, "/usr/local/bundle/gems/actionpack-5.1.7/lib/action_controller/metal/request_forgery_protection.rb", 211]
I, [2020-09-27T03:25:43.021131 #1]  INFO -- : ["APPLIED", :require_login, "app/controllers/awesome_controller.rb", 17]
I, [2020-09-27T03:25:43.022063 #1]  INFO -- : ["NO_APPLIED", :set_awesome, "app/controllers/awesome_controller.rb", 25]
I, [2020-09-27T03:25:43.023716 #1]  INFO -- : ["APPLIED", :with_readonly, "app/controllers/awesome_controller.rb", 21]
I, [2020-09-27T03:25:43.025547 #1]  INFO -- : ["ACTION", :index, "app/controllers/awesome_controller.rb", 7]
I, [2020-09-27T03:25:43.026297 #1]  INFO -- : ["APPLIED", :with_readonly, "app/controllers/awesome_controller.rb", 21]
I, [2020-09-27T03:25:43.027203 #1]  INFO -- : ["APPLIED", :store_location, "app/controllers/awesome_controller.rb", 27]
I, [2020-09-27T03:25:43.030074 #1]  INFO -- : ["APPLIED", :verify_same_origin_request, "/usr/local/bundle/gems/actionpack-5.1.7/lib/action_controller/metal/request_forgery_protection.rb", 240]
I, [2020-09-27T03:25:43.030776 #1]  INFO -- : 

Filters are put in the order in which is executed.
Notice around_action is put 2 times around action though called 1 time.

Normally log is put in this format:

["APPLIED", :require_login, "app/controllers/awesome_controller.rb", 17]

1. State. One of APPLIED, NO_APPLIED and ACTION.
   APPLIED: Filter is executed.
   NO_APPLIED: Filter is registered but not executed.
   ACTION: Called action.
2. Method name. When filter is a Proc, just put :Proc.
3. File path. In your application directory, it's omitted path. See Configuration section for details.
4. Method line no.

When filter is an object, log is put in this format:

["UNRECOGNIZED", #<Awesome::Object:0x00007f95c35768f8>]

We can't recognize the filter is actually executed or not.

To customize how to output log, add config/initializers/action_tracer.rb:

ActionTracer.configure do |config|
  # when you want to omit source_location path
  config.omitted_source_location_paths = ["#{Dir.pwd}/"]
  # e.g.
  # config.omitted_source_location_paths = []
  #   ["APPLIED", :require_login, "/Users/makicamel/works/github.com/makicamel/myapp/app/controllers/awesome_controller.rb", 17]
  # config.omitted_source_location_paths = ["#{Dir.pwd}/"]
  #   ["APPLIED", :require_login, "app/controllers/awesome_controller.rb", 17]

  # when you want to output log to stdout
  config.logger = Rails.logger
end

• omitted_source_location_paths: Omitted source_location path. In default ["#{Dir.pwd}/"].
• logger: Injectable logger. For example, to specify to output log to stdout.
• directory: The directory to put log. In default /log/.
• file_name: The log file name. In default action_tracer.log.

• Support for Rails application with ActiveController::API
• Log rotate

Bug reports and pull requests are welcome on GitHub at https://github.com/makicamel/action_tracer. This project is intended to be a safe, welcoming space for collaboration.

The gem is available as open source under the terms of the MIT License.

Everyone interacting in the ActionTracer project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.