I don't know how to initialize information in a model before it is saved.
For example. I have a model called Car, and it has the attributes wheel_size, color, etc... I want to initialize these attributes depending on other factors for each new car.
This is how I'm doing it right now.
Class Car < ActiveRecord::Base
before_save :initial_information
def initial_information
self.color = value1
self.wheel_size = value2
end
end
after_initialize
would be the best lifecycle hook
You want to do this initialization as early as possible; ideally immediately after the information you depend on is set. I'd recommend writing custom setter methods for the attributes these values depend on and initializing them there.
So, something like:
def value1=(new_value1)
self["value1"] = new_value1
self.color = new_value1
end
Alternatively, if these values can be directly calculated from the dependent variables, it's much better to simply use a normal method.
def color
return self.value1
end
by doing an after_initialize :mymethod
your method mymethod will be called after the initialize (which is the constructor in ruby's objects) :]
