Does not sync blobs on Object Storage when is not enabled

Add some checks to skip file transfers on a Geo secondary
node when file is stored on Object Storage but syncing
object storage is disabled or the object storage is
not configure for the data type on the secondary node.

ee/lib/gitlab/geo/replication/blob_downloader.rb

@@ -87,11 +87,27 @@ module Gitlab
             unless ensure_destination_path_exists
               return failure_result(reason: 'Skipping transfer as we cannot create the destination directory')
             end
+          else
+            unless sync_object_storage_enabled?
+              return failure_result(reason: 'Skipping transfer as this secondary node is not allowed to replicate content on Object Storage')
+            end
+
+            unless object_store_enabled?
+              return failure_result(reason: "Skipping transfer as this secondary node is not configured to store #{replicator.replicable_name} on Object Storage")
+            end
           end
 
           nil
         end
 
+        def sync_object_storage_enabled?
+          Gitlab::Geo.current_node.sync_object_storage
+        end
+
+        def object_store_enabled?
+          carrierwave_uploader.class.object_store_enabled?
+        end
+
         def absolute_path
           carrierwave_uploader.path
         end

ee/spec/lib/gitlab/geo/replication/blob_downloader_spec.rb

@@ -52,6 +52,40 @@ RSpec.describe Gitlab::Geo::Replication::BlobDownloader do
 
         xit 'ensures the file destination directory exists' # Not worth testing here as-is. Extract the functionality first.
       end
+
+      context 'when the file is on Object Storage' do
+        before do
+          stub_package_file_object_storage(enabled: true, direct_upload: true)
+        end
+
+        let!(:model_record) { create(:package_file, :npm, :object_storage) }
+
+        subject { described_class.new(replicator: model_record.replicator) }
+
+        context 'with object storage sync disabled' do
+          before do
+            secondary.update_column(:sync_object_storage, false)
+          end
+
+          it 'returns failure' do
+            result = subject.execute
+
+            expect(result.success).to be_falsey
+          end
+        end
+
+        context 'with object storage disabled' do
+          before do
+            stub_package_file_object_storage(enabled: false)
+          end
+
+          it 'returns failure' do
+            result = subject.execute
+
+            expect(result.success).to be_falsey
+          end
+        end
+      end
     end
 
     context 'when an error occurs while getting a Tempfile' do