activerecord - Parent object eager load nested associations Rails -

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in rails 4 have following models

class parent < activerecord::base  has_many :sons  has_many :grand_sons, through: sons   scope :load_tree, (id) -> {parent.includes(sons: [:grand_sons]).find(id)} end  class son < activerecord::base   belongs_to :parent   has_many :grand_sons end  class grandson < activerecord::base   belongs_to :son end

with load_tree obtain object like:

{    id: 1,    sons: [           {              id: 1,              parent_id: 1,              grand_sons:[ { id: 1, son_id: 1, } , ...]           }, ...         ]  }

but after doing tree = parent.load_tree(1) got tree # <parent id=1> tree.sons #[<son id=1>, <son id =2>] seems not able eager load objects, suggestions?

try 

parent.includes(:sons, {:sons => :grand_sons}).find(id)

my understanding is, must specify relationship nested associations explicitly.


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