validations.markdown

Validations via ActiveModel::Validations

Valuable doesn't support validations because other people are already doing that well. Here are examples of using the ActiveModel gem for validations:

  class Entity < Valuable
    include ActiveModel::Validations
  
    has_value :name
    has_value :avatar
  
    validates_presence_of :name
    validates_presence_of :avatar
  end
  
  >> entity = Entity.new(:name => 'Crystaline Entity')
  
  >> entity.valid?
  => false
  
  >> entity.errors.full_messages
  => ["Avatar can't be blank"]

Example using validators

less talk; more code:

  class BorgValidator < ActiveModel::Validator
    def validate( entity )
      if( entity.name.to_s == "" )
        entity.errors[:name] << 'is blank and will be assimilated.'
      elsif( entity.name !~ /(\d+) of (\d+)/ )
        entity.errors[:name] << 'does not conform and will be assimilated.'
      end
    end
  end
  
  class Entity < Valuable
    include ActiveModel::Validations
    validates_with BorgValidator
  
    has_value :name
  
    validates_presence_of :name
  end
  
  >> hugh = Entity.new(:name => 'Hugh')
  
  >> hugh.valid?
  => false
  
  >> hugh.errors.full_messages
  => ["Name does not conform and will be assimilated"]
  
  >> high = Entity.new(:name => '3 of 7')
  
  >> hugh.valid?
  => true