Save project_repository only for hashed storage

When a new project is created, or migrated to hashed storage,
create/update the project repository row.

app/models/project.rb

@@ -120,7 +120,7 @@ class Project < ActiveRecord::Base
   after_create :ensure_storage_path_exists
   after_save :ensure_storage_path_exists, if: :namespace_id_changed?
 
-  after_create :create_project_repository
+  after_create :save_project_repository
 
   acts_as_ordered_taggable
 
@@ -1210,8 +1210,17 @@ class Project < ActiveRecord::Base
     false
   end
 
-  def create_project_repository
-    update(project_repository: ProjectRepository.create!(shard_name: repository_storage, disk_path: disk_path))
+  def save_project_repository
+    return unless hashed_storage?(:repository)
+
+    project_repo = project_repository || build_project_repository
+    project_repo.assign_attributes(shard_name: repository_storage, disk_path: disk_path)
+
+    if project_repo.persisted?
+      project_repo.save
+    else
+      update(project_repository: project_repo)
+    end
   end
 
   def create_repository(force: false)

app/services/projects/hashed_storage/migrate_repository_service.rb

@@ -32,6 +32,7 @@ module Projects
 
         if result
           project.write_repository_config
+          project.create_project_repository
         else
           rollback_folder_move
           project.storage_version = nil

spec/models/project_spec.rb

@@ -1730,16 +1730,28 @@ describe Project do
     end
   end
 
-  describe '#create_project_repository' do
+  describe '#save_project_repository' do
     let(:project) { create(:project, :repository) }
 
     it 'creates a project_repository' do
-      project.create_project_repository
+      project.save_project_repository
 
-      expect(project).to have_project_repository
+      expect(project.reload.project_repository).to be_present
       expect(project.project_repository.disk_path).to eq(project.disk_path)
       expect(project.project_repository.shard_name).to eq(project.repository_storage)
     end
+
+    it 'updates the project_repository' do
+      project.save_project_repository
+
+      allow(project).to receive(:disk_path).and_return('@fancy/new/path')
+
+      expect do
+        project.save_project_repository
+      end.not_to change(ProjectRepository, :count)
+
+      expect(project.reload.project_repository.disk_path).to eq(project.disk_path)
+    end
   end
 
   describe '#create_repository' do