class Product < ActiveRecord::Base
validates_presence_of :title, :description, :image_url
validates_numericality_of :price
validate :price_must_be_at_least_a_cent
validates_uniqueness_of :title
validates_format_of :image_url,
:with=>%r{\.(gif|jpg|png)$}i,
:massege=>'must be a URL for GIF, JPG '+
'or PNG image.'
protected
def price_must_be_at_least_a_cent
errors.add(:price, 'should be at least 0.01') if price.nil? || price<0.01
end
end
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gem install mysql -- --with-mysql-config=/usr/bin/mysql_config
