Module: ActiveEntity::Reflection::ClassMethods

Defined in:
lib/active_entity/reflection.rb

Overview

Reflection enables the ability to examine the associations and aggregations of Active Entity classes and objects. This information, for example, can be used in a form builder that takes an Active Entity object and creates input fields for all of the attributes depending on their type and displays the associations to other objects.

MacroReflection class has info for AggregateReflection and AssociationReflection classes.

Instance Method Summary collapse

Instance Method Details

#_reflect_on_association(association) ⇒ Object

:nodoc:



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# File 'lib/active_entity/reflection.rb', line 123

def _reflect_on_association(association) #:nodoc:
  _reflections[association.to_s]
end

#clear_reflections_cache ⇒ Object

:nodoc:



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# File 'lib/active_entity/reflection.rb', line 127

def clear_reflections_cache # :nodoc:
  @__reflections = nil
end

#reflect_on_aggregation(aggregation) ⇒ Object

Returns the AggregateReflection object for the named aggregation (use the symbol).

Account.reflect_on_aggregation(:balance) # => the balance AggregateReflection



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# File 'lib/active_entity/reflection.rb', line 71

def reflect_on_aggregation(aggregation)
  aggregate_reflections[aggregation.to_s]
end

#reflect_on_all_aggregations ⇒ Object

Returns an array of AggregateReflection objects for all the aggregations in the class.



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# File 'lib/active_entity/reflection.rb', line 63

def reflect_on_all_aggregations
  aggregate_reflections.values
end

#reflect_on_all_associations(macro = nil) ⇒ Object

Returns an array of AssociationReflection objects for all the associations in the class. If you only want to reflect on a certain association type, pass in the symbol (:has_many, :has_one, :belongs_to) as the first parameter.

Example:

Account.reflect_on_all_associations             # returns an array of all associations
Account.reflect_on_all_associations(:has_many)  # returns an array of all has_many associations



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# File 'lib/active_entity/reflection.rb', line 108

def reflect_on_all_associations(macro = nil)
  association_reflections = reflections.values
  association_reflections.select! { |reflection| reflection.macro == macro } if macro
  association_reflections
end

#reflect_on_association(association) ⇒ Object

Returns the AssociationReflection object for the association (use the symbol).

Account.reflect_on_association(:owner)             # returns the owner AssociationReflection
Invoice.reflect_on_association(:line_items).macro  # returns :has_many



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# File 'lib/active_entity/reflection.rb', line 119

def reflect_on_association(association)
  reflections[association.to_s]
end

#reflections ⇒ Object

Returns a Hash of name of the reflection as the key and an AssociationReflection as the value.

Account.reflections # => {"balance" => AggregateReflection}



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# File 'lib/active_entity/reflection.rb', line 79

def reflections
  @__reflections ||= begin
                       ref = {}

                       _reflections.each do |name, reflection|
                         parent_reflection = reflection.parent_reflection

                         if parent_reflection
                           parent_name = parent_reflection.name
                           ref[parent_name.to_s] = parent_reflection
                         else
                           ref[name] = reflection
                         end
                       end

                       ref
                     end
end