Add deprecation guard to prevent further usage of NamespaceService

Namespace service is in process of being deprecated since it is not
compatible with Gitaly HA. Hence, we want to prevent future usage of it
by forcing callers to wrap Namespace Service calls in an allow block

app/models/concerns/storage/legacy_namespace.rb

@@ -57,18 +57,20 @@ module Storage
       # Move the namespace directory in all storages used by member projects
       repository_storages(legacy_only: true).each do |repository_storage|
         # Ensure old directory exists before moving it
-        gitlab_shell.add_namespace(repository_storage, full_path_before_last_save)
+        Gitlab::GitalyClient::NamespaceService.allow do
+          gitlab_shell.add_namespace(repository_storage, full_path_before_last_save)
 
-        # Ensure new directory exists before moving it (if there's a parent)
-        gitlab_shell.add_namespace(repository_storage, parent.full_path) if parent
+          # Ensure new directory exists before moving it (if there's a parent)
+          gitlab_shell.add_namespace(repository_storage, parent.full_path) if parent
 
-        unless gitlab_shell.mv_namespace(repository_storage, full_path_before_last_save, full_path)
+          unless gitlab_shell.mv_namespace(repository_storage, full_path_before_last_save, full_path)
 
-          Rails.logger.error "Exception moving path #{repository_storage} from #{full_path_before_last_save} to #{full_path}" # rubocop:disable Gitlab/RailsLogger
+            Rails.logger.error "Exception moving path #{repository_storage} from #{full_path_before_last_save} to #{full_path}" # rubocop:disable Gitlab/RailsLogger
 
-          # if we cannot move namespace directory we should rollback
-          # db changes in order to prevent out of sync between db and fs
-          raise Gitlab::UpdatePathError.new('namespace directory cannot be moved')
+            # if we cannot move namespace directory we should rollback
+            # db changes in order to prevent out of sync between db and fs
+            raise Gitlab::UpdatePathError.new('namespace directory cannot be moved')
+          end
         end
       end
     end
@@ -95,13 +97,15 @@ module Storage
         # We will remove it later async
         new_path = "#{full_path}+#{id}+deleted"
 
-        if gitlab_shell.mv_namespace(repository_storage, full_path, new_path)
-          Gitlab::AppLogger.info %Q(Namespace directory "#{full_path}" moved to "#{new_path}")
+        Gitlab::GitalyClient::NamespaceService.allow do
+          if gitlab_shell.mv_namespace(repository_storage, full_path, new_path)
+            Gitlab::AppLogger.info %Q(Namespace directory "#{full_path}" moved to "#{new_path}")
 
-          # Remove namespace directory async with delay so
-          # GitLab has time to remove all projects first
-          run_after_commit do
-            GitlabShellWorker.perform_in(5.minutes, :rm_namespace, repository_storage, new_path)
+            # Remove namespace directory async with delay so
+            # GitLab has time to remove all projects first
+            run_after_commit do
+              GitlabShellWorker.perform_in(5.minutes, :rm_namespace, repository_storage, new_path)
+            end
           end
         end
       end

app/workers/gitlab_shell_worker.rb

@@ -8,6 +8,8 @@ class GitlabShellWorker
   latency_sensitive_worker!
 
   def perform(action, *arg)
-    gitlab_shell.__send__(action, *arg) # rubocop:disable GitlabSecurity/PublicSend
+    Gitlab::GitalyClient::NamespaceService.allow do
+      gitlab_shell.__send__(action, *arg) # rubocop:disable GitlabSecurity/PublicSend
+    end
   end
 end

lib/gitlab/database/rename_reserved_paths_migration/v1/rename_namespaces.rb

@@ -66,11 +66,13 @@ module Gitlab
           def move_repositories(namespace, old_full_path, new_full_path)
             repo_shards_for_namespace(namespace).each do |repository_storage|
               # Ensure old directory exists before moving it
-              gitlab_shell.add_namespace(repository_storage, old_full_path)
+              Gitlab::GitalyClient::NamespaceService.allow do
+                gitlab_shell.add_namespace(repository_storage, old_full_path)
 
-              unless gitlab_shell.mv_namespace(repository_storage, old_full_path, new_full_path)
-                message = "Exception moving on shard #{repository_storage} from #{old_full_path} to #{new_full_path}"
-                Rails.logger.error message # rubocop:disable Gitlab/RailsLogger
+                unless gitlab_shell.mv_namespace(repository_storage, old_full_path, new_full_path)
+                  message = "Exception moving on shard #{repository_storage} from #{old_full_path} to #{new_full_path}"
+                  Rails.logger.error message # rubocop:disable Gitlab/RailsLogger
+                end
               end
             end
           end

lib/gitlab/gitaly_client/namespace_service.rb

@@ -3,7 +3,22 @@
 module Gitlab
   module GitalyClient
     class NamespaceService
+      extend Gitlab::TemporarilyAllow
+
+      NamespaceServiceAccessError = Class.new(StandardError)
+      ALLOW_KEY = :allow_namespace
+
+      def self.allow
+        temporarily_allow(ALLOW_KEY) { yield }
+      end
+
+      def self.denied?
+        !temporarily_allowed?(ALLOW_KEY)
+      end
+
       def initialize(storage)
+        raise NamespaceServiceAccessError if self.class.denied?
+
         @storage = storage
       end
 

spec/lib/gitlab/shell_spec.rb

@@ -401,7 +401,7 @@ describe Gitlab::Shell do
 
     describe '#add_namespace' do
       it 'creates a namespace' do
-        subject.add_namespace(storage, "mepmep")
+        Gitlab::GitalyClient::NamespaceService.allow { subject.add_namespace(storage, "mepmep") }
 
         expect(TestEnv.storage_dir_exists?(storage, "mepmep")).to be(true)
       end
@@ -425,8 +425,10 @@ describe Gitlab::Shell do
 
     describe '#remove' do
       it 'removes the namespace' do
-        subject.add_namespace(storage, "mepmep")
-        subject.rm_namespace(storage, "mepmep")
+        Gitlab::GitalyClient::NamespaceService.allow do
+          subject.add_namespace(storage, "mepmep")
+          subject.rm_namespace(storage, "mepmep")
+        end
 
         expect(TestEnv.storage_dir_exists?(storage, "mepmep")).to be(false)
       end
@@ -434,8 +436,10 @@ describe Gitlab::Shell do
 
     describe '#mv_namespace' do
       it 'renames the namespace' do
-        subject.add_namespace(storage, "mepmep")
-        subject.mv_namespace(storage, "mepmep", "2mep")
+        Gitlab::GitalyClient::NamespaceService.allow do
+          subject.add_namespace(storage, "mepmep")
+          subject.mv_namespace(storage, "mepmep", "2mep")
+        end
 
         expect(TestEnv.storage_dir_exists?(storage, "mepmep")).to be(false)
         expect(TestEnv.storage_dir_exists?(storage, "2mep")).to be(true)