Extend custom CSS cache time with digest paths (#33207)

spec/helpers/theme_helper_spec.rb

@@ -79,6 +79,26 @@ RSpec.describe ThemeHelper do
     end
   end
 
+  describe '#custom_stylesheet' do
+    context 'when custom css setting value digest is present' do
+      before { Rails.cache.write(:setting_digest_custom_css, '1a2s3d4f1a2s3d4f') }
+
+      it 'returns value from settings' do
+        expect(custom_stylesheet)
+          .to match('/css/custom-1a2s3d4f.css')
+      end
+    end
+
+    context 'when custom css setting value digest is not present' do
+      before { Rails.cache.delete(:setting_digest_custom_css) }
+
+      it 'returns default value' do
+        expect(custom_stylesheet)
+          .to be_blank
+      end
+    end
+  end
+
   private
 
   def html_links

spec/models/form/admin_settings_spec.rb

@@ -17,4 +17,40 @@ RSpec.describe Form::AdminSettings do
       end
     end
   end
+
+  describe '#save' do
+    describe 'updating digest values' do
+      context 'when updating custom css to real value' do
+        subject { described_class.new(custom_css: css) }
+
+        let(:css) { 'body { color: red; }' }
+        let(:digested) { Digest::SHA256.hexdigest(css) }
+
+        it 'changes relevant digest value' do
+          expect { subject.save }
+            .to(change { Rails.cache.read(:setting_digest_custom_css) }.to(digested))
+        end
+      end
+
+      context 'when updating custom css to empty value' do
+        subject { described_class.new(custom_css: '') }
+
+        before { Rails.cache.write(:setting_digest_custom_css, 'previous-value') }
+
+        it 'changes relevant digest value' do
+          expect { subject.save }
+            .to(change { Rails.cache.read(:setting_digest_custom_css) }.to(be_blank))
+        end
+      end
+
+      context 'when updating other fields' do
+        subject { described_class.new(site_contact_email: 'test@example.host') }
+
+        it 'does not update digests' do
+          expect { subject.save }
+            .to(not_change { Rails.cache.read(:setting_digest_custom_css) })
+        end
+      end
+    end
+  end
 end

spec/requests/cache_spec.rb

@@ -10,6 +10,7 @@ module TestEndpoints
     /.well-known/nodeinfo
     /nodeinfo/2.0
     /manifest
+    /css/custom-1a2s3d4f.css
     /custom.css
     /actor
     /api/v1/instance/extended_description

spec/requests/custom_css_spec.rb

@@ -5,10 +5,10 @@ require 'rails_helper'
 RSpec.describe 'Custom CSS' do
   include RoutingHelper
 
-  describe 'GET /custom.css' do
+  describe 'GET /css/:id.css' do
     context 'without any CSS or User Roles' do
       it 'returns empty stylesheet' do
-        get '/custom.css'
+        get '/css/custom-123.css'
 
         expect(response)
           .to have_http_status(200)
@@ -27,7 +27,7 @@ RSpec.describe 'Custom CSS' do
       end
 
       it 'returns stylesheet from settings' do
-        get '/custom.css'
+        get '/css/custom-456.css'
 
         expect(response)
           .to have_http_status(200)

spec/routing/custom_css_routing_spec.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe 'Custom CSS routes' do
+  describe 'the legacy route' do
+    it 'routes to correct place' do
+      expect(get('/custom.css'))
+        .to route_to('custom_css#show')
+    end
+  end
+
+  describe 'the custom digest route' do
+    it 'routes to correct place' do
+      expect(get('/css/custom-1a2s3d4f.css'))
+        .to route_to('custom_css#show', id: 'custom-1a2s3d4f', format: 'css')
+    end
+  end
+end