I'm building a marketplace app in Rails 4. When entering products, sellers can enter a price and a saleprice. SalePrice is optional.
My current validations below check for values greater than 0. How do I add a validation for - saleprice must be at least 5% lower than price.
validates :price, numericality: {greater_than: 0}
validates :saleprice, numericality: {greater_than: 0}, :allow_blank => true
you can use custom validation
validate :saleprice_lower_than_price
def saleprice_lower_than_price
if (saleprice != nil && saleprice > (price - (price * 0.05))
errors.add(:saleprice, "Sale price should be 5% less than price")
end
end
You'll need to write your own custom validation method, there is a good explanation in the rails guides: http://guides.rubyonrails.org/active_record_validations.html#custom-methods
Just create a custom validation method
validate :saleprice_lower_than_price
def saleprice_lower_than_price
(price - saleprice) > price * 0.05
end
Optionally you can add condition in this method to add errors to your object, like
errors.add(:saleprice, 'should be lower')
