Rename namespace-paths in a migration helper

3 files changed, 232 insertions, 0 deletions

diff --git a/lib/gitlab/database/rename_reserved_paths_migration.rb b/lib/gitlab/database/rename_reserved_paths_migration.rb
new file mode 100644
index 00000000000..ad5570b4c72
--- /dev/null
+++ b/lib/gitlab/database/rename_reserved_paths_migration.rb
@@ -0,0 +1,35 @@
+module Gitlab
+  module Database
+    module RenameReservedPathsMigration
+      include MigrationHelpers
+      include Namespaces
+      include Projects
+
+      def rename_wildcard_paths(one_or_more_paths)
+        paths = Array(one_or_more_paths)
+        rename_namespaces(paths, type: :wildcard)
+      end
+
+      def rename_root_paths(paths)
+        paths = Array(paths)
+        rename_namespaces(paths, type: :top_level)
+      end
+
+      def rename_path(namespace_path, path_was)
+        counter = 0
+        path = "#{path_was}#{counter}"
+
+        while route_exists?(File.join(namespace_path, path))
+          counter += 1
+          path = "#{path_was}#{counter}"
+        end
+
+        path
+      end
+
+      def route_exists?(full_path)
+        MigrationClasses::Route.where(Route.arel_table[:path].matches(full_path)).any?
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/database/rename_reserved_paths_migration/migration_classes.rb b/lib/gitlab/database/rename_reserved_paths_migration/migration_classes.rb
new file mode 100644
index 00000000000..a919d250541
--- /dev/null
+++ b/lib/gitlab/database/rename_reserved_paths_migration/migration_classes.rb
@@ -0,0 +1,84 @@
+module Gitlab
+  module Database
+    module RenameReservedPathsMigration
+      module MigrationClasses
+        class User < ActiveRecord::Base
+          self.table_name = 'users'
+        end
+
+        class Namespace < ActiveRecord::Base
+          self.table_name = 'namespaces'
+          belongs_to :parent,
+                     class_name: "#{MigrationClasses.name}::Namespace"
+          has_one :route, as: :source
+          has_many :children,
+                   class_name: "#{MigrationClasses.name}::Namespace",
+                   foreign_key: :parent_id
+          belongs_to :owner,
+                     class_name: "#{MigrationClasses.name}::User"
+
+          # Overridden to have the correct `source_type` for the `route` relation
+          def self.name
+            'Namespace'
+          end
+
+          def full_path
+            if route && route.path.present?
+              @full_path ||= route.path
+            else
+              update_route if persisted?
+
+              build_full_path
+            end
+          end
+
+          def build_full_path
+            if parent && path
+              parent.full_path + '/' + path
+            else
+              path
+            end
+          end
+
+          def update_route
+            prepare_route
+            route.save
+          end
+
+          def prepare_route
+            route || build_route(source: self)
+            route.path = build_full_path
+            route.name = build_full_name
+            @full_path = nil
+            @full_name = nil
+          end
+
+          def build_full_name
+            if parent && name
+              parent.human_name + ' / ' + name
+            else
+              name
+            end
+          end
+
+          def human_name
+            owner&.name
+          end
+        end
+
+        class Route < ActiveRecord::Base
+          self.table_name = 'routes'
+          belongs_to :source, polymorphic: true
+        end
+
+        class Project < ActiveRecord::Base
+          self.table_name = 'projects'
+
+          def repository_storage_path
+            Gitlab.config.repositories.storages[repository_storage]['path']
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/database/rename_reserved_paths_migration/namespaces.rb b/lib/gitlab/database/rename_reserved_paths_migration/namespaces.rb
new file mode 100644
index 00000000000..f8fbeaa990a
--- /dev/null
+++ b/lib/gitlab/database/rename_reserved_paths_migration/namespaces.rb
@@ -0,0 +1,113 @@
+module Gitlab
+  module Database
+    module RenameReservedPathsMigration
+      module Namespaces
+        include Gitlab::ShellAdapter
+
+        def rename_namespaces(paths, type:)
+          namespaces_for_paths(paths, type: type).each do |namespace|
+            rename_namespace(namespace)
+          end
+        end
+
+        def namespaces_for_paths(paths, type:)
+          namespaces = if type == :wildcard
+                         MigrationClasses::Namespace.where.not(parent_id: nil)
+                       elsif type == :top_level
+                         MigrationClasses::Namespace.where(parent_id: nil)
+                       end
+          namespaces.where(path: paths.map(&:downcase))
+        end
+
+        def rename_namespace(namespace)
+          old_path = namespace.path
+          old_full_path = namespace.full_path
+          # Only remove the last occurrence of the path name to get the parent namespace path
+          namespace_path = remove_last_occurrence(old_full_path, old_path)
+          new_path = rename_path(namespace_path, old_path)
+          new_full_path = if namespace_path.present?
+                            File.join(namespace_path, new_path)
+                          else
+                            new_path
+                          end
+
+          # skips callbacks & validations
+          MigrationClasses::Namespace.where(id: namespace).
+            update_all(path: new_path)
+
+          replace_statement = replace_sql(Route.arel_table[:path],
+                                          old_full_path,
+                                          new_full_path)
+
+          update_column_in_batches(:routes, :path, replace_statement)  do |table, query|
+            query.where(MigrationClasses::Route.arel_table[:path].matches("#{old_full_path}%"))
+          end
+
+          move_repositories(namespace, old_full_path, new_full_path)
+          move_namespace_folders(uploads_dir, old_full_path, new_full_path) if file_storage?
+          move_namespace_folders(pages_dir, old_full_path, new_full_path)
+        end
+
+        def move_namespace_folders(directory, old_relative_path, new_relative_path)
+          old_path = File.join(directory, old_relative_path)
+          return unless File.directory?(old_path)
+
+          new_path = File.join(directory, new_relative_path)
+          FileUtils.mv(old_path, new_path)
+        end
+
+        def move_repositories(namespace, old_full_path, new_full_path)
+          repo_paths_for_namespace(namespace).each do |repository_storage_path|
+            # Ensure old directory exists before moving it
+            gitlab_shell.add_namespace(repository_storage_path, old_full_path)
+
+            unless gitlab_shell.mv_namespace(repository_storage_path, old_full_path, new_full_path)
+              message = "Exception moving path #{repository_storage_path} \
+                           from #{old_full_path} to #{new_full_path}"
+              Rails.logger.error message
+            end
+          end
+        end
+
+        def repo_paths_for_namespace(namespace)
+          projects_for_namespace(namespace).
+            select('distinct(repository_storage)').map(&:repository_storage_path)
+        end
+
+        def projects_for_namespace(namespace)
+          namespace_ids = child_ids_for_parent(namespace, ids: [namespace.id])
+          namespace_or_children = MigrationClasses::Project.
+                                    arel_table[:namespace_id].
+                                    in(namespace_ids)
+          MigrationClasses::Project.unscoped.where(namespace_or_children)
+        end
+
+        # This won't scale to huge trees, but it should do for a handful of
+        # namespaces called `system`.
+        def child_ids_for_parent(namespace, ids: [])
+          namespace.children.each do |child|
+            ids << child.id
+            child_ids_for_parent(child, ids: ids) if child.children.any?
+          end
+          ids
+        end
+
+        def remove_last_occurrence(string, pattern)
+          string.reverse.sub(pattern.reverse, "").reverse
+        end
+
+        def file_storage?
+          CarrierWave::Uploader::Base.storage == CarrierWave::Storage::File
+        end
+
+        def uploads_dir
+          File.join(CarrierWave.root, "uploads")
+        end
+
+        def pages_dir
+          Settings.pages.path
+        end
+      end
+    end
+  end
+end