Adds instrumentation to several ends in ActionController::Base. It also provides some hooks related with process_action. This allows an ORM like Active Record and/or DataMapper to plug in ActionController and show related information.

Check ActiveRecord::Railties::ControllerRuntime for an example.

Namespace
Methods
A
C
P
R
S
Instance Public methods
process_action(*args)

Source: show | on GitHub 

# File actionpack/lib/action_controller/metal/instrumentation.rb, line 19
def process_action(*args)
  raw_payload = {
    controller: self.class.name,
    action: action_name,
    params: request.filtered_parameters,
    headers: request.headers,
    format: request.format.ref,
    method: request.request_method,
    path: request.fullpath
  }

  ActiveSupport::Notifications.instrument("start_processing.action_controller", raw_payload.dup)

  ActiveSupport::Notifications.instrument("process_action.action_controller", raw_payload) do |payload|
    begin
      result = super
      payload[:status] = response.status
      result
    ensure
      append_info_to_payload(payload)
    end
  end
end
redirect_to(*args)

Source: show | on GitHub 

# File actionpack/lib/action_controller/metal/instrumentation.rb, line 64
def redirect_to(*args)
  ActiveSupport::Notifications.instrument("redirect_to.action_controller") do |payload|
    result = super
    payload[:status]   = response.status
    payload[:location] = response.filtered_location
    result
  end
end
render(*args)

Source: show | on GitHub 

# File actionpack/lib/action_controller/metal/instrumentation.rb, line 43
def render(*args)
  render_output = nil
  self.view_runtime = cleanup_view_runtime do
    Benchmark.ms { render_output = super }
  end
  render_output
end
send_data(data, options = {})

Source: show | on GitHub 

# File actionpack/lib/action_controller/metal/instrumentation.rb, line 58
def send_data(data, options = {})
  ActiveSupport::Notifications.instrument("send_data.action_controller", options) do
    super
  end
end
send_file(path, options = {})

Source: show | on GitHub 

# File actionpack/lib/action_controller/metal/instrumentation.rb, line 51
def send_file(path, options = {})
  ActiveSupport::Notifications.instrument("send_file.action_controller",
    options.merge(path: path)) do
    super
  end
end
Instance Private methods
append_info_to_payload(payload)

Every time after an action is processed, this method is invoked with the payload, so you can add more information.

Source: show | on GitHub 

# File actionpack/lib/action_controller/metal/instrumentation.rb, line 92
def append_info_to_payload(payload) # :doc:
  payload[:view_runtime] = view_runtime
end
cleanup_view_runtime()

A hook which allows you to clean up any time, wrongly taken into account in views, like database querying time.

def cleanup_view_runtime
  super - time_taken_in_something_expensive
end

Source: show | on GitHub 

# File actionpack/lib/action_controller/metal/instrumentation.rb, line 86
def cleanup_view_runtime # :doc:
  yield
end