List sites by most recent audit checked_at date

app/controllers/sites_controller.rb

@@ -4,7 +4,7 @@ class SitesController < ApplicationController
 
   # GET /sites
   def index
-    @pagy, @sites = pagy Site.sort_by_audit_url.includes(:audit)
+    @pagy, @sites = pagy Site.sort_by_audit_date.includes(:audit)
   end
 
   # GET /sites/1

app/models/audit.rb

@@ -14,7 +14,7 @@ class Audit < ApplicationRecord
     "failed",     # All checks failed
   ].index_by(&:itself), validate: true, default: :pending
 
-  scope :sort_by_newest, -> { order(created_at: :desc) }
+  scope :sort_by_newest, -> { order(checked_at: :desc) }
   scope :sort_by_url, -> { order(Arel.sql("REGEXP_REPLACE(audits.url, '^https?://(www\.)?', '') ASC")) }
   scope :past, -> { where.not(status: :pending) }
 

app/models/site.rb

@@ -15,6 +15,14 @@ class Site < ApplicationRecord
       .order("sites.id, sortable_url")
     from(subquery, :sites).order(:sortable_url)
   end
+  scope :sort_by_audit_date, -> do
+    joins("LEFT JOIN (
+        SELECT site_id, MAX(checked_at) as latest_check
+        FROM audits
+        GROUP BY site_id
+      ) latest_audits ON sites.id = latest_audits.site_id")
+    .order("latest_audits.latest_check DESC NULLS LAST, sites.created_at DESC")
+  end
 
   class << self
     def find_or_create_by_url(attributes)

spec/models/audit_spec.rb

@@ -43,10 +43,10 @@
   describe "scopes" do
     before { site.audit.destroy }
 
-    it ".sort_by_newest returns audits in descending order by creation date" do
-      oldest = create(:audit, site:, created_at: 3.days.ago)
-      older = create(:audit, site:, created_at: 2.days.ago)
-      newer = create(:audit, site:, created_at: 1.day.ago)
+    it ".sort_by_newest returns audits in descending order by checked_at date" do
+      oldest = create(:audit, site:, checked_at: 3.days.ago)
+      older = create(:audit, site:, checked_at: 2.days.ago)
+      newer = create(:audit, site:, checked_at: 1.day.ago)
 
       expect(described_class.sort_by_newest).to eq([newer, older, oldest])
     end

spec/models/site_spec.rb

@@ -20,37 +20,47 @@
     end
   end
 
-  describe ".find_or_create_by_url" do
-    let(:http_url) { "http://example.com" }
+  describe "scopes" do
+    it ".sort_by_audit_date orders sites by their most recent audit checked_at date" do
+      site1 = build(:site, audits: [build(:audit, checked_at: 1.day.ago)]).tap(&:save)
+      site2 = build(:site, audits: [build(:audit, checked_at: 5.days.ago)]).tap(&:save)
+      site3 = build(:site, audits: [build(:audit, checked_at: 2.days.ago)]).tap(&:save)
 
-    context "when site with URL exists" do
-      let!(:existing_site) { described_class.create(url:) }
+      expect(described_class.sort_by_audit_date).to eq([site1, site3, site2])
+    end
 
-      it "returns existing site for exact URL match" do
-        expect(described_class.find_or_create_by_url(url:)).to eq(existing_site)
-      end
+    describe ".find_or_create_by_url" do
+      let(:http_url) { "http://example.com" }
 
-      it "returns existing site when only scheme differs" do
-        expect(described_class.find_or_create_by_url(url: http_url)).to eq(existing_site)
-      end
+      context "when site with URL exists" do
+        let!(:existing_site) { described_class.create(url:) }
 
-      it "finds site with historical URLs" do
-        new_url = "https://new-example.com"
-        existing_site.audits.create!(url: new_url)
+        it "returns existing site for exact URL match" do
+          expect(described_class.find_or_create_by_url(url:)).to eq(existing_site)
+        end
 
-        expect(described_class.find_or_create_by_url(url:)).to eq(existing_site)
-        expect(described_class.find_or_create_by_url(url: new_url)).to eq(existing_site)
+        it "returns existing site when only scheme differs" do
+          expect(described_class.find_or_create_by_url(url: http_url)).to eq(existing_site)
+        end
+
+        it "finds site with historical URLs" do
+          new_url = "https://new-example.com"
+          existing_site.audits.create!(url: new_url)
+
+          expect(described_class.find_or_create_by_url(url:)).to eq(existing_site)
+          expect(described_class.find_or_create_by_url(url: new_url)).to eq(existing_site)
+        end
       end
-    end
 
-    context "when site does not exist" do
-      it "creates a new site with audit" do
-        expect {
-          site = described_class.find_or_create_by_url(url:)
-          expect(site).to be_persisted
-          expect(site.audit.url).to eq(url)
-        }.to change(described_class, :count).by(1)
-         .and change(Audit, :count).by(1)
+      context "when site does not exist" do
+        it "creates a new site with audit" do
+          expect {
+            site = described_class.find_or_create_by_url(url:)
+            expect(site).to be_persisted
+            expect(site.audit.url).to eq(url)
+          }.to change(described_class, :count).by(1)
+          .and change(Audit, :count).by(1)
+        end
       end
     end
   end