Contents

module Rein
  module Constraint
    # This module contains methods for defining numericality constraints.
    module Numericality
      OPERATORS = {
        greater_than: :>,
        greater_than_or_equal_to: :>=,
        equal_to: :"=",
        not_equal_to: :"!=",
        less_than: :<,
        less_than_or_equal_to: :<=
      }.freeze

      def add_numericality_constraint(table, attribute, options = {})
        name = "#{table}_#{attribute}"

        conditions = OPERATORS.slice(*options.keys).map do |key, operator|
          value = options[key]
          [attribute, operator, value].join(" ")
        end.join(" AND ")

        if options[:if].present?
          conditions = "NOT (#{options[:if]}) OR (#{conditions})"
        end

        execute("ALTER TABLE #{table} ADD CONSTRAINT #{name} CHECK (#{conditions})")
      end

      def remove_numericality_constraint(table, attribute)
        name = "#{table}_#{attribute}"
        execute("ALTER TABLE #{table} DROP CONSTRAINT #{name}")
      end
    end
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
rein-2.0.0	lib/rein/constraint/numericality.rb