state tracking

gistfile1.txt

    state_machine :state, initial: :init do

      before_transition any => any do |transition|
        @status_before_transition = transition.state_name
      end

      after_transition any => any do |transition|
        log = "#{@status_before_transition} -> #{transition.state_name}"
        SystemEvent.create(trackable: transition, description: log, tag: "state_change")
      end

gistfile2.txt

CREATE TABLE system_events (
    id integer NOT NULL,
    tag character varying NOT NULL,
    description text,
    trackable_id integer,
    trackable_type character varying,
    created_at timestamp without time zone NOT NULL,
    updated_at timestamp without time zone NOT NULL
);

gistfile3.txt

add in manage event tracking 

system_event.rb

class SystemEvent < ApplicationRecord
  belongs_to :trackable, optional: true, polymorphic: true
end