Added Rollbacker workers and support on the rake task

Rollback is done similar to Migration for the Hashed Storage.
It also shares the same ExclusiveLease key to prevent both happening
at the same time.

All Hashed Storage related workers now share the same queue namespace
which allows for assigning dedicated workers easily.

3 files changed, 42 insertions, 6 deletions

diff --git a/lib/gitlab/hashed_storage/migrator.rb b/lib/gitlab/hashed_storage/migrator.rb
index 73ed57ea584..7046b4e2a43 100644
--- a/lib/gitlab/hashed_storage/migrator.rb
+++ b/lib/gitlab/hashed_storage/migrator.rb
@@ -13,10 +13,18 @@ module Gitlab
       #
       # @param [Integer] start first project id for the range
       # @param [Integer] finish last project id for the range
-      def bulk_schedule(start:, finish:)
+      def bulk_schedule_migration(start:, finish:)
         ::HashedStorage::MigratorWorker.perform_async(start, finish)
       end
 
+      # Schedule a range of projects to be bulk rolledback with #bulk_rollback asynchronously
+      #
+      # @param [Integer] start first project id for the range
+      # @param [Integer] finish last project id for the range
+      def bulk_schedule_rollback(start:, finish:)
+        ::HashedStorage::RollbackerWorker.perform_async(start, finish)
+      end
+
       # Start migration of projects from specified range
       #
       # Flagging a project to be migrated is a synchronous action
@@ -34,6 +42,23 @@ module Gitlab
       end
       # rubocop: enable CodeReuse/ActiveRecord
 
+      # Start rollback of projects from specified range
+      #
+      # Flagging a project to be rolled back is a synchronous action
+      # but the rollback runs through async jobs
+      #
+      # @param [Integer] start first project id for the range
+      # @param [Integer] finish last project id for the range
+      # rubocop: disable CodeReuse/ActiveRecord
+      def bulk_rollback(start:, finish:)
+        projects = build_relation(start, finish)
+
+        projects.with_route.find_each(batch_size: BATCH_SIZE) do |project|
+          rollback(project)
+        end
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
+
       # Flag a project to be migrated to Hashed Storage
       #
       # @param [Project] project that will be migrated
diff --git a/lib/gitlab/hashed_storage/rake_helper.rb b/lib/gitlab/hashed_storage/rake_helper.rb
index 38f552fab03..87a31a37e3f 100644
--- a/lib/gitlab/hashed_storage/rake_helper.rb
+++ b/lib/gitlab/hashed_storage/rake_helper.rb
@@ -24,7 +24,7 @@ module Gitlab
       end
 
       # rubocop: disable CodeReuse/ActiveRecord
-      def self.project_id_batches(&block)
+      def self.project_id_batches_migration(&block)
         Project.with_unmigrated_storage.in_batches(of: batch_size, start: range_from, finish: range_to) do |relation| # rubocop: disable Cop/InBatches
           ids = relation.pluck(:id)
 
@@ -34,6 +34,16 @@ module Gitlab
       # rubocop: enable CodeReuse/ActiveRecord
 
       # rubocop: disable CodeReuse/ActiveRecord
+      def self.project_id_batches_rollback(&block)
+        Project.with_storage_feature(:repository).in_batches(of: batch_size, start: range_from, finish: range_to) do |relation| # rubocop: disable Cop/InBatches
+          ids = relation.pluck(:id)
+
+          yield ids.min, ids.max
+        end
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
+
+      # rubocop: disable CodeReuse/ActiveRecord
       def self.legacy_attachments_relation
         Upload.joins(<<~SQL).where('projects.storage_version < :version OR projects.storage_version IS NULL', version: Project::HASHED_STORAGE_FEATURES[:attachments])
           JOIN projects
diff --git a/lib/tasks/gitlab/storage.rake b/lib/tasks/gitlab/storage.rake
index b759a2dad3a..a2136ce1b92 100644
--- a/lib/tasks/gitlab/storage.rake
+++ b/lib/tasks/gitlab/storage.rake
@@ -36,8 +36,8 @@ namespace :gitlab do
 
       print "Enqueuing migration of #{legacy_projects_count} projects in batches of #{helper.batch_size}"
 
-      helper.project_id_batches do |start, finish|
-        storage_migrator.bulk_schedule(start: start, finish: finish)
+      helper.project_id_batches_migration do |start, finish|
+        storage_migrator.bulk_schedule_migration(start: start, finish: finish)
 
         print '.'
       end
@@ -81,8 +81,9 @@ namespace :gitlab do
 
       print "Enqueuing rollback of #{hashed_projects_count} projects in batches of #{helper.batch_size}"
 
-      helper.project_id_batches do |start, finish|
-        storage_migrator.bulk_schedule(start: start, finish: finish, operation: :rollback)
+      helper.project_id_batches_rollback do |start, finish|
+        puts "Start: #{start} FINISH: #{finish}"
+        storage_migrator.bulk_schedule_rollback(start: start, finish: finish)
 
         print '.'
       end