Class: Perpetuity::Dereferencer

Inherits:
Object
  • Object
show all
Defined in:
lib/perpetuity/dereferencer.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(mapper_registry, identity_map = IdentityMap.new) ⇒ Dereferencer

Returns a new instance of Dereferencer.



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# File 'lib/perpetuity/dereferencer.rb', line 8

def initialize mapper_registry, identity_map=IdentityMap.new
  @map = identity_map
  @mapper_registry = mapper_registry
end

Instance Attribute Details

#map ⇒ Object (readonly)

Returns the value of attribute map.



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# File 'lib/perpetuity/dereferencer.rb', line 6

def map
  @map
end

#mapper_registry ⇒ Object (readonly)

Returns the value of attribute mapper_registry.



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# File 'lib/perpetuity/dereferencer.rb', line 6

def mapper_registry
  @mapper_registry
end

Instance Method Details

#[](reference) ⇒ Object 



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# File 'lib/perpetuity/dereferencer.rb', line 25

def [] reference
  if referenceable?(reference)
    map[reference.klass, reference.id]
  else
    reference
  end
end

#cache(objects) ⇒ Object 



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# File 'lib/perpetuity/dereferencer.rb', line 21

def cache objects
  objects.each { |object| map << object }
end

#grouped(references) ⇒ Object 



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# File 'lib/perpetuity/dereferencer.rb', line 33

def grouped references
  references.group_by(&:klass)
end

#load(references) ⇒ Object 



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# File 'lib/perpetuity/dereferencer.rb', line 13

def load references
  references = Array(references).flatten.select {|ref| referenceable?(ref) }

  cache grouped(references).map { |klass, refs|
    objects klass, refs.map(&:id)
  }.flatten
end

#objects(klass, ids) ⇒ Object 



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# File 'lib/perpetuity/dereferencer.rb', line 37

def objects klass, ids
  ids = ids.uniq
  if ids.one?
    mapper_registry.mapper_for(klass, identity_map: map).find(ids.first)
  elsif ids.none?
    []
  else
    mapper_registry[klass].find(ids.uniq).to_a
  end
end

#referenceable?(ref) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/perpetuity/dereferencer.rb', line 48

def referenceable? ref
  [:klass, :id].all? { |msg| ref.respond_to?(msg) }
end