Module: ActiveGraph::Shared::Typecaster

Defined in:
lib/active_graph/shared/typecaster.rb

Overview

This module provides a convenient way of registering a custom Typecasting class. Custom Typecasters all follow a simple pattern.

EXAMPLE:

.. code-block

ruby

class RangeConverter class << self def primitive_type String end

  def convert_type
    Range
  end

  def to_db(value)
    value.to_s
  end

  def to_ruby(value)
    ends = value.to_s.split('..').map { |d| Integer(d) }
    ends[0]..ends[1]
  end
  alias_method :call, :to_ruby
end

include ActiveGraph::Shared::Typecaster
end

This would allow you to use property :my_prop, type: Range in a model. Each method and the alias_method call is required. Make sure the module inclusion happens at the end of the file.

primitive_type is used to fool ActiveAttr's type converters, which only recognize a few basic Ruby classes.

convert_type must match the constant given to the type option.

to_db provides logic required to transform your value into the class defined by primitive_type

to_ruby provides logic to transform the DB-provided value back into the class expected by code using the property. In other words, it should match the convert_type.

Note that alias_method is used to make to_ruby respond to call. This is to provide compatibility with ActiveAttr.

Class Method Summary collapse

Class Method Details

.included(other) ⇒ Object 



48
49
50
 
# File 'lib/active_graph/shared/typecaster.rb', line 48

def self.included(other)
  ActiveGraph::Shared::TypeConverters.register_converter(other)
end