Move code to a BackgroundMigration

And run in intervals.

db/post_migrate/20181010133639_backfill_store_project_full_path_in_repo.rb

@@ -3,134 +3,25 @@
 class BackfillStoreProjectFullPathInRepo < ActiveRecord::Migration
   include Gitlab::Database::MigrationHelpers
 
-  DOWNTIME = false
+  DOWNTIME       = false
+  BATCH_SIZE     = 1_000
+  DELAY_INTERVAL = 5.minutes
+  UP_MIGRATION   = 'BackfillProjectFullpathInRepoConfig::Up'
+  DOWN_MIGRATION = 'BackfillProjectFullpathInRepoConfig::Down'
 
-  class Repository
-    attr_reader :storage
-
-    def initialize(storage, relative_path)
-      @storage = storage
-      @relative_path = relative_path
-    end
-
-    def gitaly_repository
-      Gitaly::Repository.new(storage_name: @storage, relative_path: @relative_path)
-    end
-  end
-
-  module Storage
-    class HashedProject
-      attr_accessor :project
-
-      ROOT_PATH_PREFIX = '@hashed'.freeze
-
-      def initialize(project)
-        @project = project
-      end
-
-      def disk_path
-        "#{ROOT_PATH_PREFIX}/#{disk_hash[0..1]}/#{disk_hash[2..3]}/#{disk_hash}"
-      end
-
-      def disk_hash
-        @disk_hash ||= Digest::SHA2.hexdigest(project.id.to_s) if project.id
-      end
-    end
-
-    class LegacyProject
-      attr_accessor :project
-
-      def initialize(project)
-        @project = project
-      end
-
-      def disk_path
-        project.full_path
-      end
-    end
-  end
-
-  module Routable
-    extend ActiveSupport::Concern
-
-    def full_path
-      @full_path ||= build_full_path
-    end
-
-    def build_full_path
-      if parent && path
-        parent.full_path + '/' + path
-      else
-        path
-      end
-    end
-  end
-
-  class Namespace < ActiveRecord::Base
-    self.table_name = 'namespaces'
-
-    include Routable
-
-    belongs_to :parent, class_name: "Namespace"
-  end
+  disable_ddl_transaction!
 
   class Project < ActiveRecord::Base
     self.table_name = 'projects'
 
-    include Routable
     include EachBatch
-
-    FULLPATH_CONFIG_KEY = 'gitlab.fullpath'
-
-    belongs_to :namespace
-    delegate :disk_path, to: :storage
-    alias_method :parent, :namespace
-
-    def add_fullpath_config
-      entries = { FULLPATH_CONFIG_KEY => full_path }
-
-      repository_service.set_config(entries)
-    end
-
-    def remove_fullpath_config
-      repository_service.delete_config([FULLPATH_CONFIG_KEY])
-    end
-
-    def storage
-      @storage ||=
-        if hashed_storage?
-          Storage::HashedProject.new(self)
-        else
-          Storage::LegacyProject.new(self)
-        end
-    end
-
-    def hashed_storage?
-      self.storage_version && self.storage_version >= 1
-    end
-
-    def repository
-      @repository ||= Repository.new(repository_storage, disk_path + '.git')
-    end
-
-    def repository_service
-      @repository_service ||= Gitlab::GitalyClient::RepositoryService.new(repository)
-    end
   end
 
   def up
-    Project.each_batch do |batch|
-      batch.each do |project|
-        project.add_fullpath_config
-      end
-    end
+    queue_background_migration_jobs_by_range_at_intervals(Project, UP_MIGRATION, DELAY_INTERVAL)
   end
 
   def down
-    Project.each_batch do |batch|
-      batch.each do |project|
-        project.remove_fullpath_config
-      end
-    end
+    queue_background_migration_jobs_by_range_at_intervals(Project, DOWN_MIGRATION, DELAY_INTERVAL)
   end
 end

lib/gitlab/background_migration/backfill_project_fullpath_in_repo_config.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    # This module is used to write the full path of all projects to
+    # the git repository config file.
+    # Storing the full project path in the git config allows admins to
+    # easily identify a project when it is using hashed storage.
+    module BackfillProjectFullpathInRepoConfig
+      module Storage
+        # Class that returns the disk path for a project using hashed storage
+        class HashedProject
+          attr_accessor :project
+
+          ROOT_PATH_PREFIX = '@hashed'.freeze
+
+          def initialize(project)
+            @project = project
+          end
+
+          def disk_path
+            "#{ROOT_PATH_PREFIX}/#{disk_hash[0..1]}/#{disk_hash[2..3]}/#{disk_hash}"
+          end
+
+          def disk_hash
+            @disk_hash ||= Digest::SHA2.hexdigest(project.id.to_s) if project.id
+          end
+        end
+
+        # Class that returns the disk path for a project using legacy storage
+        class LegacyProject
+          attr_accessor :project
+
+          def initialize(project)
+            @project = project
+          end
+
+          def disk_path
+            project.full_path
+          end
+        end
+      end
+
+      # Concern used by Project and Namespace to determine the full
+      # route the the project
+      module Routable
+        extend ActiveSupport::Concern
+
+        def full_path
+          @full_path ||= build_full_path
+        end
+
+        def build_full_path
+          if parent && path
+            parent.full_path + '/' + path
+          else
+            path
+          end
+        end
+      end
+
+      # Class used to interact with repository using Gitaly
+      class Repository
+        attr_reader :storage
+
+        def initialize(storage, relative_path)
+          @storage = storage
+          @relative_path = relative_path
+        end
+
+        def gitaly_repository
+          Gitaly::Repository.new(storage_name: @storage, relative_path: @relative_path)
+        end
+      end
+
+      # Namespace can be a user or group. It can be the root or a
+      # child of another namespace.
+      class Namespace < ActiveRecord::Base
+        self.table_name = 'namespaces'
+
+        include Routable
+
+        belongs_to :parent, class_name: "Namespace"
+      end
+
+      # Project is where the repository (etc.) is stored
+      class Project < ActiveRecord::Base
+        self.table_name = 'projects'
+
+        include Routable
+        include EachBatch
+
+        FULLPATH_CONFIG_KEY = 'gitlab.fullpath'
+
+        belongs_to :namespace
+        delegate :disk_path, to: :storage
+        alias_method :parent, :namespace
+
+        def add_fullpath_config
+          entries = { FULLPATH_CONFIG_KEY => full_path }
+
+          repository_service.set_config(entries)
+        end
+
+        def remove_fullpath_config
+          repository_service.delete_config([FULLPATH_CONFIG_KEY])
+        end
+
+        def storage
+          @storage ||=
+            if hashed_storage?
+              Storage::HashedProject.new(self)
+            else
+              Storage::LegacyProject.new(self)
+            end
+        end
+
+        def hashed_storage?
+          self.storage_version && self.storage_version >= 1
+        end
+
+        def repository
+          @repository ||= Repository.new(repository_storage, disk_path + '.git')
+        end
+
+        def repository_service
+          @repository_service ||= Gitlab::GitalyClient::RepositoryService.new(repository)
+        end
+      end
+
+      # Class to add the fullpath to the git repo config
+      class Up
+        def perform(start_id, end_id)
+          Project.where(id: start_id..end_id).each do |project|
+            project.add_fullpath_config
+          end
+        end
+      end
+
+      # Class to rollback adding the fullpath to the git repo config
+      class Down
+        def perform(start_id, end_id)
+          Project.where(id: start_id..end_id).each do |project|
+            project.remove_fullpath_config
+          end
+        end
+      end
+    end
+  end
+end

spec/migrations/backfill_store_project_full_path_in_repo_spec.rb

@@ -12,6 +12,12 @@ describe BackfillStoreProjectFullPathInRepo, :migration do
 
   subject(:migration) { described_class.new }
 
+  around do |example|
+    Sidekiq::Testing.inline! do
+      example.run
+    end
+  end
+
   describe '#up' do
     shared_examples_for 'writes the full path to git config' do
       it 'writes the git config' do