feat: use gin index for message search (#11107)

This PR updates the search implementation to better utilize the GIN
indexes. The option is toggled behind a feature flag for us to test it
internally before making it available publicly

spec/services/search_service_spec.rb

@@ -67,16 +67,61 @@ describe SearchService do
     end
 
     context 'when message search' do
+      let!(:message2) { create(:message, account: account, inbox: inbox, content: 'harry is cool') }
+
       it 'searches across message content and return in created_at desc' do
         # random messages in another account
         create(:message, content: 'Harry Potter is a wizard')
         # random messsage in inbox with out access
         create(:message, account: account, inbox: create(:inbox, account: account), content: 'Harry Potter is a wizard')
-        message2 = create(:message, account: account, inbox: inbox, content: 'harry is cool')
         params = { q: 'Harry' }
         search = described_class.new(current_user: user, current_account: account, params: params, search_type: 'Message')
         expect(search.perform[:messages].map(&:id)).to eq([message2.id, message.id])
       end
+
+      context 'with feature flag for search type' do
+        let(:params) { { q: 'Harry' } }
+        let(:search_type) { 'Message' }
+
+        it 'uses LIKE search when search_with_gin feature is disabled' do
+          allow(account).to receive(:feature_enabled?).with('search_with_gin').and_return(false)
+          search_service = described_class.new(current_user: user, current_account: account, params: params, search_type: search_type)
+
+          expect(search_service).to receive(:filter_messages_with_like).and_call_original
+          expect(search_service).not_to receive(:filter_messages_with_gin)
+
+          search_service.perform
+        end
+
+        it 'uses GIN search when search_with_gin feature is enabled' do
+          allow(account).to receive(:feature_enabled?).with('search_with_gin').and_return(true)
+          search_service = described_class.new(current_user: user, current_account: account, params: params, search_type: search_type)
+
+          expect(search_service).to receive(:filter_messages_with_gin).and_call_original
+          expect(search_service).not_to receive(:filter_messages_with_like)
+
+          search_service.perform
+        end
+
+        it 'returns same results regardless of search type' do
+          # Create test messages
+          message3 = create(:message, account: account, inbox: inbox, content: 'Harry is a wizard apprentice')
+
+          # Test with GIN search
+          allow(account).to receive(:feature_enabled?).with('search_with_gin').and_return(true)
+          gin_search = described_class.new(current_user: user, current_account: account, params: params, search_type: search_type)
+          gin_results = gin_search.perform[:messages].map(&:id)
+
+          # Test with LIKE search
+          allow(account).to receive(:feature_enabled?).with('search_with_gin').and_return(false)
+          like_search = described_class.new(current_user: user, current_account: account, params: params, search_type: search_type)
+          like_results = like_search.perform[:messages].map(&:id)
+
+          # Both search types should return the same messages
+          expect(gin_results).to match_array(like_results)
+          expect(gin_results).to include(message.id, message2.id, message3.id)
+        end
+      end
     end
 
     context 'when conversation search' do
@@ -99,4 +144,23 @@ describe SearchService do
       end
     end
   end
+
+  describe '#use_gin_search' do
+    let(:params) { { q: 'test' } }
+
+    it 'checks if the account has the search_with_gin feature enabled' do
+      expect(account).to receive(:feature_enabled?).with('search_with_gin')
+      search.send(:use_gin_search)
+    end
+
+    it 'returns true when search_with_gin feature is enabled' do
+      allow(account).to receive(:feature_enabled?).with('search_with_gin').and_return(true)
+      expect(search.send(:use_gin_search)).to be true
+    end
+
+    it 'returns false when search_with_gin feature is disabled' do
+      allow(account).to receive(:feature_enabled?).with('search_with_gin').and_return(false)
+      expect(search.send(:use_gin_search)).to be false
+    end
+  end
 end