Make presenter for popular links

app/presenters/formats/popular_links_presenter.rb

@@ -0,0 +1,47 @@
+module Formats
+  class PopularLinksPresenter
+    # Unlike presenter for other models which inherit from editions model,
+    # PopularLinksPresenter do not inherit from EditionFormatPresenter
+    # This is because Edition presenter has dependency on Artifact and
+    # Popular links are not coupled with Artefact unlike any other models.
+    # Hence the difference
+    def initialize(popular_links_edition)
+      @popular_links_edition = popular_links_edition
+    end
+
+    def render_for_publishing_api(republish: false)
+      required_fields.merge optional_fields
+    end
+
+  private
+
+    attr_reader :popular_links_edition
+
+    def required_fields
+      {
+        title: popular_links_edition.title,
+        schema_name: "link_collection",
+        document_type: "link_collection",
+        public_updated_at: public_updated_at.rfc3339(3),
+        publishing_app: "publisher",
+        rendering_app: "frontend",
+        details:,
+      }
+    end
+
+    def details
+      {
+        link_items: popular_links_edition.link_items,
+      }
+    end
+
+    def optional_fields
+      access_limited = { auth_bypass_ids: [popular_links_edition.auth_bypass_id] }
+      { access_limited:, public_updated_at: public_updated_at.rfc3339(3) }
+    end
+
+    def public_updated_at
+      popular_links_edition.public_updated_at || popular_links_edition.updated_at
+    end
+  end
+end

test/unit/presenters/formats/popular_links_format_presenter_test.rb

@@ -0,0 +1,33 @@
+require "test_helper"
+
+class PopularLinksFormatPresenterTest < ActiveSupport::TestCase
+  def subject
+    Formats::PopularLinksPresenter.new(FactoryBot.create(:popular_links, major_change: true))
+  end
+
+  context "#render_for_publishing_api" do
+    setup do
+      @result = subject.render_for_publishing_api
+    end
+
+    should "have expected required fields" do
+      assert_equal "Homepage Popular Links", @result[:title]
+      assert_equal "link_collection", @result[:schema_name]
+      assert_equal "link_collection", @result[:document_type]
+      assert_equal "publisher", @result[:publishing_app]
+      assert_equal "frontend", @result[:rendering_app]
+      assert_equal ({ link_items: [{ url: "https://www.url1.com", title: "title1" },
+                                   { url: "https://www.url2.com", title: "title2" },
+                                   { url: "https://www.url3.com", title: "title3" },
+                                   { url: "https://www.url4.com", title: "title4" },
+                                   { url: "https://www.url5.com", title: "title5" },
+                                   { url: "https://www.url6.com", title: "title6" }] }),
+                   @result[:details]
+    end
+
+    should "have expected optional fields" do
+      assert_not_empty @result[:access_limited]
+      assert_not_empty @result[:public_updated_at]
+    end
+  end
+end