Module: Historiographer::HistoryMigrationMysql

Included in:
ActiveRecord::ConnectionAdapters::TableDefinition
Defined in:
lib/historiographer/history_migration_mysql.rb

Instance Method Summary collapse

Instance Method Details

#histories(except: [], only: [], no_business_columns: false, index_names: {}) ⇒ Object

class CreateAdGroupHistories < ActiveRecord::Migration

def change
  create_table :ad_group_histories do |t|
    t.histories
  end
end

end

t.histories(except: [“name”]) # don’t include name column t.histories(only: [“name”]) # only include name column t.histories(no_business_columns: true) # only add history timestamps and history_user_id; manually add your own columns

Will automatically add user_id, history_started_at, and history_ended_at columns



19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
 
# File 'lib/historiographer/history_migration_mysql.rb', line 19

def histories(except: [], only: [], no_business_columns: false, index_names: {})
  index_names.symbolize_keys!

  original_table_name = self.name.gsub(/_histories$/) { }.pluralize
  foreign_key = original_table_name.singularize.foreign_key

  class_definer = Class.new(ActiveRecord::Base) do
  end

  class_name = original_table_name.classify
  klass = Object.const_set(class_name, class_definer)
  original_columns = klass.columns.reject { |c| c.name == "id" || except.include?(c.name) || (only.any? && only.exclude?(c.name)) || no_business_columns }

  integer foreign_key.to_sym, null: false

  original_columns.each do |column|
    opts = {}
    opts.merge!(column.as_json.clone)

    send(column.type, column.name, opts.symbolize_keys!)
  end

  datetime :history_started_at, null: false
  datetime :history_ended_at
  integer :history_user_id

  index :history_started_at
  index :history_ended_at
  index :history_user_id
  index foreign_key

  ActiveRecord::Base.connection.indexes(original_table_name).each do |index|
    index index.columns
  end
end