how to call includes method before expose

[lazybios]

I use grape entity in below way. And got a n+1 warning in expose :roles methods. I need know how can I call includes(:roles) methods before exposed. Thks！

Model

class User
  has_many :roles
end

class Role
   belongs_to :user
end

Entity

class User < Grape::Entity
  expose :roles do |obj, _opts|
    obj.roles.map(&:name)
  end
end

[jonathanpa]

@lazybios did you find how to avoid n+1 queries ?

[c0ze]

I think you need to call includes in the controller, when fetching the objects from db.

something like

respond_with User.where(your_params).includes(:roles), with: UserEntity

not sure this can be done at the entity layer.

[Jayzen]

call includes in the model will solve the N+1 warning

class User
  has_many :roles

  def roles
      self.where(your_params).includes(:roles)
  end
end