Add InvalidateElementsCacheJob

In larger applications it might be the case that one product, variant
or taxon is assigned to thousands of elements via one of our
three ingredients. The current implementation does not perform
very well. Using a active job that can be backgrounded and has an
optimized algorithm to touch all elements, their parent elements and
pages should improve performance.

Author: tvdeyen

app/decorators/models/alchemy/solidus/spree_product_decorator.rb

@@ -4,7 +4,8 @@ module Alchemy
   module Solidus
     module SpreeProductDecorator
       def self.prepended(base)
-        base.include Alchemy::Solidus::TouchAlchemyIngredients
+        # Solidus runs touch callbacks on product after_save
+        base.after_touch :touch_alchemy_ingredients
         base.has_many :alchemy_ingredients, class_name: "Alchemy::Ingredients::SpreeProduct", as: :related_object, dependent: :nullify
       end
 
@@ -23,6 +24,12 @@ def touch_taxons
         taxons.each(&:touch)
       end
 
+      # Touch all elements that have this product assigned to one of its ingredients.
+      # This cascades to all parent elements and pages as well.
+      def touch_alchemy_ingredients
+        InvalidateElementsCacheJob.perform_later("SpreeProduct", id)
+      end
+
       ::Spree::Product.prepend self
     end
   end

app/decorators/models/alchemy/solidus/spree_taxon_decorator.rb

@@ -4,11 +4,20 @@ module Alchemy
   module Solidus
     module SpreeTaxonDecorator
       def self.prepended(base)
-        base.include Alchemy::Solidus::TouchAlchemyIngredients
+        base.after_update :touch_alchemy_ingredients
+        base.after_touch :touch_alchemy_ingredients
         base.has_many :alchemy_ingredients, class_name: "Alchemy::Ingredients::SpreeTaxon", as: :related_object, dependent: :nullify
       end
 
       ::Spree::Taxon.prepend self
+
+      private
+
+      # Touch all elements that have this taxon assigned to one of its ingredients.
+      # This cascades to all parent elements and pages as well.
+      def touch_alchemy_ingredients
+        InvalidateElementsCacheJob.perform_later("SpreeTaxon", id)
+      end
     end
   end
 end

app/decorators/models/alchemy/solidus/spree_variant_decorator.rb

@@ -4,11 +4,20 @@ module Alchemy
   module Solidus
     module SpreeVariantDecorator
       def self.prepended(base)
-        base.include Alchemy::Solidus::TouchAlchemyIngredients
+        base.after_update :touch_alchemy_ingredients
+        base.after_touch :touch_alchemy_ingredients
         base.has_many :alchemy_ingredients, class_name: "Alchemy::Ingredients::SpreeVariant", as: :related_object, dependent: :nullify
       end
 
       ::Spree::Variant.prepend self
+
+      private
+
+      # Touch all elements that have this variant assigned to one of its ingredients.
+      # This cascades to all parent elements and pages as well.
+      def touch_alchemy_ingredients
+        InvalidateElementsCacheJob.perform_later("SpreeVariant", id)
+      end
     end
   end
 end

app/jobs/alchemy/solidus/base_job.rb

@@ -0,0 +1,7 @@
+module Alchemy
+  module Solidus
+    class BaseJob < ActiveJob::Base
+      retry_on ActiveRecord::Deadlocked
+    end
+  end
+end

app/jobs/alchemy/solidus/invalidate_elements_cache_job.rb

@@ -0,0 +1,39 @@
+module Alchemy
+  module Solidus
+    class InvalidateElementsCacheJob < BaseJob
+      queue_as :default
+
+      def perform(model_name, id)
+        now = Time.current
+
+        element_ids = model(model_name)
+          .where("related_object_id" => id)
+          .joins(:element)
+          .pluck("alchemy_elements.id")
+        elements = ::Alchemy::Element.where(id: element_ids)
+
+        all_element_ids = get_all_element_ids(elements, element_ids)
+        ::Alchemy::Element.where(id: all_element_ids.uniq).update_all(updated_at: now)
+
+        page_ids = elements.joins(page_version: :page).pluck("alchemy_pages.id")
+        ::Alchemy::Page.where(id: page_ids.uniq).update_all(updated_at: now)
+      end
+
+      private
+
+      def get_all_element_ids(elements, element_ids)
+        parent_element_ids = elements.pluck(:parent_element_id).compact
+        parent_elements = ::Alchemy::Element.distinct.where(id: parent_element_ids)
+
+        if parent_elements.any?
+          element_ids += parent_element_ids
+          get_all_element_ids(parent_elements, element_ids)
+        end
+
+        element_ids
+      end
+
+      def model(model_name) = "Alchemy::Ingredients::#{model_name}".constantize
+    end
+  end
+end

app/models/alchemy/solidus/touch_alchemy_ingredients.rb

@@ -18,7 +18,7 @@
   # Configure public file server for tests with Cache-Control for performance.
   config.public_file_server.enabled = true
   config.public_file_server.headers = {
-    "Cache-Control" => "public, max-age=#{1.hour.to_i}",
+    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
   }
 
   # Show full error reports and disable caching.
@@ -35,7 +35,7 @@
   # Store uploaded files on the local file system in a temporary directory.
   config.active_storage.service = :test
 
-  config.active_job.queue_adapter = :inline
+  config.active_job.queue_adapter = :test
 
   config.action_mailer.perform_caching = false
 

spec/dummy/config/environments/test.rb

@@ -0,0 +1,38 @@
+require "rails_helper"
+
+RSpec.describe Alchemy::Solidus::InvalidateElementsCacheJob, type: :job do
+  let(:job) { described_class.new }
+
+  subject { job.perform("SpreeProduct", product.id) }
+
+  let(:page) { create(:alchemy_page, :public, updated_at: 1.week.ago) }
+
+  let!(:element) do
+    create(:alchemy_element, page_version: page.draft_version, ingredients: [ingredient], updated_at: 1.day.ago)
+  end
+
+  describe "perform" do
+    let(:product) { create(:product) }
+    let(:ingredient) { Alchemy::Ingredients::SpreeProduct.create(related_object: product, role: "product") }
+
+    it "touches the element" do
+      expect { subject }.to change { element.reload.updated_at }
+    end
+
+    context "when the element has a parent" do
+      let!(:parent_element) do
+        create(:alchemy_element, page_version: page.draft_version, updated_at: 1.day.ago).tap do |parent|
+          element.update_column(:parent_element_id, parent.id)
+        end
+      end
+
+      it "touches the parent element" do
+        expect { subject }.to change { parent_element.reload.updated_at }
+      end
+    end
+
+    it "touches the page" do
+      expect { subject }.to change { page.reload.updated_at }
+    end
+  end
+end

spec/jobs/alchemy/solidus/invalidate_elements_cache_job_spec.rb

@@ -11,38 +11,34 @@
     let(:element) { create(:alchemy_element, page_version: page_version) }
     let(:product) { create(:product) }
 
-    context "if assigned to ingredient spree taxon" do
+    context "if assigned to ingredient spree product" do
       let!(:ingredient) { Alchemy::Ingredients::SpreeProduct.create!(element: element, role: "product", related_object: product) }
 
       it "invalidates the cache on update" do
-        travel_to 5.minutes.from_now do
-          current_time = Time.current
-          expect { product.reload.update!(name: "New name") }.to change { ingredient.reload.updated_at }.to(current_time)
-          expect(element.reload.updated_at).to eq(current_time)
-          expect(page_version.reload.updated_at).to eq(current_time)
-          expect(page.reload.updated_at).to eq(current_time)
-        end
+        expect {
+          product.update!(name: "New name")
+        }.to enqueue_job(Alchemy::Solidus::InvalidateElementsCacheJob).with("SpreeProduct", product.id)
       end
 
       it "invalidates the cache on touch" do
-        travel_to 5.minutes.from_now do
-          current_time = Time.current
-          expect { product.reload.touch }.to change { ingredient.reload.updated_at }.to(current_time)
-          expect(element.reload.updated_at).to eq(current_time)
-          expect(page_version.reload.updated_at).to eq(current_time)
-          expect(page.reload.updated_at).to eq(current_time)
-        end
+        expect {
+          product.touch
+        }.to enqueue_job(Alchemy::Solidus::InvalidateElementsCacheJob).with("SpreeProduct", product.id)
       end
     end
 
     context "if assigned to taxon that is assigned to ingredient spree taxon" do
       let(:taxon) { create(:taxon) }
-      let(:product) { create(:product, taxons: [taxon]) }
+      let!(:product) { create(:product, taxons: [taxon]) }
 
       let!(:ingredient) { Alchemy::Ingredients::SpreeTaxon.create!(element: element, role: "taxon", related_object: taxon) }
 
       it "touches ingredient spree taxons elements" do
-        expect { product.reload.touch }.to change { element.reload.updated_at }
+        expect {
+          product.touch
+        }.to enqueue_job(Alchemy::Solidus::InvalidateElementsCacheJob).with("SpreeTaxon", taxon.id).and(
+          enqueue_job(Alchemy::Solidus::InvalidateElementsCacheJob).with("SpreeProduct", product.id)
+        )
       end
     end
   end

spec/models/spree/product_spec.rb

@@ -13,23 +13,15 @@
     let(:taxon) { create(:taxon) }
 
     it "invalidates the cache on update" do
-      travel_to 5.minutes.from_now do
-        current_time = Time.current
-        expect { taxon.reload.update!(name: "New name") }.to change { ingredient.reload.updated_at }.to(current_time)
-        expect(element.reload.updated_at).to eq(current_time)
-        expect(page_version.reload.updated_at).to eq(current_time)
-        expect(page.reload.updated_at).to eq(current_time)
-      end
+      expect {
+        taxon.update!(name: "New name")
+      }.to enqueue_job(Alchemy::Solidus::InvalidateElementsCacheJob).with("SpreeTaxon", taxon.id)
     end
 
     it "invalidates the cache on touch" do
-      travel_to 5.minutes.from_now do
-        current_time = Time.current
-        expect { taxon.reload.touch }.to change { ingredient.reload.updated_at }.to(current_time)
-        expect(element.reload.updated_at).to eq(current_time)
-        expect(page_version.reload.updated_at).to eq(current_time)
-        expect(page.reload.updated_at).to eq(current_time)
-      end
+      expect {
+        taxon.touch
+      }.to enqueue_job(Alchemy::Solidus::InvalidateElementsCacheJob).with("SpreeTaxon", taxon.id)
     end
   end
 end