Is there a way to establish relationships only if included?

[dahal]

For example:-

# Model
class Store < ApplicationRecord
  has_many :products
  has_many :customers
  has_many :orders
end

# Serializer
class StoreSerializer
  include FastJsonapi::ObjectSerializer
  attributes :id, :name

  has_many :products
  has_many :customers
  has_many :orders
end

# I have standard serializer (just like above) for all these models as well.
class Product < ApplicationRecord
  belongs_to :store
end

class Customer < ApplicationRecord
  has_many :orders
  belongs_to :store
end

class Order < ApplicationRecord
  belongs_to :store
  belongs_to :customer
end


customers = Customer.where(active: true).include(:orders)
ShopSerializer.new(customers)

☝️ makes N+1 database calls to Store table. What is the best way to avoid it?

[Mziserman]

I use this :

# Serializer
def include_model?(params, model)
  params[:include].present? && params[:include].include?(model)
end
has_many :orders,
         if: proc { |_record, params| include_model?(params, :orders) }

# Controller
customers = Customer.where(active: true).include(:orders)
ShopSerializer.new(customers, {include: [:orders], params: {include: [:orders]}}) # first one for fja include logic, second for params in proc

[dpikt]

A solution to #357 should fix this use case.