Typecaster¶
This module provides a convenient way of registering a custom Typecasting class. Custom Typecasters all follow a simple pattern.
EXAMPLE:
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 Neo4j::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.