Active Model Conversion
Handles default conversions: to_model, to_key, to_param, and to_partial_path.
Let’s take for example this non-persisted object.
class ContactMessage
include ActiveModel::Conversion
# ContactMessage are never persisted in the DB
def persisted?
false
end
end
cm = ContactMessage.new
cm.to_model == cm # => true
cm.to_key # => nil
cm.to_param # => nil
cm.to_partial_path # => "contact_messages/contact_message"
Class Public methods
param_delimiter Link
Accepts a string that will be used as a delimiter of object’s key values in the ‘to_param` method.
Source: | on GitHub
# File activemodel/lib/active_model/conversion.rb, line 32 class_attribute :param_delimiter, instance_reader: false, default: "-"
Instance Public methods
to_key() Link
Returns an Array of all key attributes if any of the attributes is set, whether or not the object is persisted. Returns nil if there are no key attributes.
class Person
include ActiveModel::Conversion
attr_accessor :id
def initialize(id)
@id = id
end
end
person = Person.new(1)
person.to_key # => [1]
Source: | on GitHub
# File activemodel/lib/active_model/conversion.rb, line 67 def to_key key = respond_to?(:id) && id key ? Array(key) : nil end
to_model() Link
If your object is already designed to implement all of the Active Model you can use the default :to_model implementation, which simply returns self.
class Person
include ActiveModel::Conversion
end
person = Person.new
person.to_model == person # => true
If your model does not act like an Active Model object, then you should define :to_model yourself returning a proxy object that wraps your object with Active Model compliant methods.
Source: | on GitHub
# File activemodel/lib/active_model/conversion.rb, line 49 def to_model self end
to_param() Link
Returns a string representing the object’s key suitable for use in URLs, or nil if persisted? is false.
class Person
include ActiveModel::Conversion
attr_accessor :id
def initialize(id)
@id = id
end
def persisted?
true
end
end
person = Person.new(1)
person.to_param # => "1"
Source: | on GitHub
# File activemodel/lib/active_model/conversion.rb, line 90 def to_param (persisted? && (key = to_key) && key.all?) ? key.join(self.class.param_delimiter) : nil end
to_partial_path() Link
Returns a string identifying the path associated with the object. ActionPack uses this to find a suitable partial to represent the object.
class Person
include ActiveModel::Conversion
end
person = Person.new
person.to_partial_path # => "people/person"
Source: | on GitHub
# File activemodel/lib/active_model/conversion.rb, line 103 def to_partial_path self.class._to_partial_path end