factory_bot sounds like it will do what you are trying to achieve. You can define all the common attributes in the default definition and then override them at creation time. You can also pass an id to the factory:
Factory.define :theme do |t|
t.background_color '0x000000'
t.title_text_color '0x000000',
t.component_theme_color '0x000000'
t.carrier_select_color '0x000000'
t.label_text_color '0x000000',
t.join_upper_gradient '0x000000'
t.join_lower_gradient '0x000000'
t.join_text_color '0x000000',
t.cancel_link_color '0x000000'
t.border_color '0x000000'
t.carrier_text_color '0x000000'
t.public true
end
Factory(:theme, :id => 1, :name => "Lite", :background_color => '0xC7FFD5')
Factory(:theme, :id => 2, :name => "Metallic", :background_color => '0xC7FFD5')
Factory(:theme, :id => 3, :name => "Blues", :background_color => '0x0060EC')
When used with faker it can populate a database really quickly with associations without having to mess about with Fixtures (yuck).
I have code like this in a rake task.
100.times do
Factory(:company, :address => Factory(:address), :employees => [Factory(:employee)])
end