module BackupRestore class RestoreDisabledError < RuntimeError; end class FilenameMissingError < RuntimeError; end class Restorer attr_reader :success def initialize(user_id, filename, publish_to_message_bus = false) @user_id, @filename, @publish_to_message_bus = user_id, filename, publish_to_message_bus ensure_restore_is_enabled ensure_no_operation_is_running ensure_we_have_a_user ensure_we_have_a_filename initialize_state end def run log "[STARTED]" log "'#{@user_info[:username]}' has started the restore!" mark_restore_as_running listen_for_shutdown_signal ensure_directory_exists(@tmp_directory) copy_archive_to_tmp_directory unzip_archive extract_metadata validate_metadata extract_dump restore_dump ### READ-ONLY / START ### enable_readonly_mode pause_sidekiq wait_for_sidekiq switch_schema! # TOFIX: MessageBus is busted... migrate_database reconnect_database reload_site_settings disable_readonly_mode ### READ-ONLY / END ### extract_uploads rescue SystemExit log "Restore process was cancelled!" rollback rescue => ex log "EXCEPTION: " + ex.message log ex.backtrace.join("\n") rollback else @success = true ensure notify_user rescue nil clean_up @success ? log("[SUCCESS]") : log("[FAILED]") end protected def ensure_restore_is_enabled raise Restore::RestoreDisabledError unless Rails.env.development? || SiteSetting.allow_restore? end def ensure_no_operation_is_running raise BackupRestore::OperationRunningError if BackupRestore.is_operation_running? end def ensure_we_have_a_user user = User.find_by(id: @user_id) raise Discourse::InvalidParameters.new(:user_id) unless user # keep some user data around to check them against the newly restored database @user_info = { id: user.id, username: user.username, email: user.email } end def ensure_we_have_a_filename raise Restore::FilenameMissingError if @filename.nil? end def initialize_state @success = false @db_was_changed = false @current_db = RailsMultisite::ConnectionManagement.current_db @current_version = BackupRestore.current_version @timestamp = Time.now.strftime("%Y-%m-%d-%H%M%S") @tmp_directory = File.join(Rails.root, "tmp", "restores", @current_db, @timestamp) @archive_filename = File.join(@tmp_directory, @filename) @tar_filename = @archive_filename[0...-3] @meta_filename = File.join(@tmp_directory, BackupRestore::METADATA_FILE) @dump_filename = File.join(@tmp_directory, BackupRestore::DUMP_FILE) @logs = [] @readonly_mode_was_enabled = Discourse.readonly_mode? end def listen_for_shutdown_signal Thread.new do while BackupRestore.is_operation_running? exit if BackupRestore.should_shutdown? sleep 0.1 end end end def mark_restore_as_running log "Marking restore as running..." BackupRestore.mark_as_running! end def enable_readonly_mode return if @readonly_mode_was_enabled log "Enabling readonly mode..." Discourse.enable_readonly_mode end def pause_sidekiq log "Pausing sidekiq..." Sidekiq.pause! end def wait_for_sidekiq log "Waiting for sidekiq to finish running jobs..." iterations = 1 while sidekiq_has_running_jobs? log "Waiting for sidekiq to finish running jobs... ##{iterations}" sleep 5 iterations += 1 raise "Sidekiq did not finish running all the jobs in the allowed time!" if iterations > 6 end end def sidekiq_has_running_jobs? Sidekiq::Workers.new.each do |_, _, worker| payload = worker.try(:payload) return true if payload.try(:all_sites) return true if payload.try(:current_site_id) == @current_db end false end def copy_archive_to_tmp_directory log "Copying archive to tmp directory..." source = File.join(Backup.base_directory, @filename) `cp #{source} #{@archive_filename}` end def unzip_archive log "Unzipping archive..." FileUtils.cd(@tmp_directory) { `gzip --decompress #{@archive_filename}` } end def extract_metadata log "Extracting metadata file..." FileUtils.cd(@tmp_directory) { `tar --extract --file #{@tar_filename} #{BackupRestore::METADATA_FILE}` } @metadata = Oj.load_file(@meta_filename) end def validate_metadata log "Validating metadata..." log " Current version: #{@current_version}" log " Restored version: #{@metadata["version"]}" error = "You're trying to restore a more recent version of the schema. You should migrate first!" raise error if @metadata["version"] > @current_version end def extract_dump log "Extracting dump file..." FileUtils.cd(@tmp_directory) { `tar --extract --file #{@tar_filename} #{BackupRestore::DUMP_FILE}` } end def restore_dump log "Restoring dump file... (can be quite long)" logs = Queue.new psql_running = true has_error = false Thread.new do RailsMultisite::ConnectionManagement::establish_connection(db: @current_db) while psql_running message = logs.pop.strip has_error ||= (message =~ /ERROR:/) log(message) unless message.blank? end end IO.popen("#{psql_command} 2>&1") do |pipe| begin while line = pipe.readline logs << line end rescue EOFError # finished reading... ensure psql_running = false logs << "" end end # psql does not return a valid exit code when an error happens raise "psql failed" if has_error end def psql_command db_conf = BackupRestore.database_configuration password_argument = "PGPASSWORD=#{db_conf.password}" if db_conf.password.present? host_argument = "--host=#{db_conf.host}" if db_conf.host.present? port_argument = "--port=#{db_conf.port}" if db_conf.port.present? username_argument = "--username=#{db_conf.username}" if db_conf.username.present? [ password_argument, # pass the password to psql (if any) "psql", # the psql command "--dbname='#{db_conf.database}'", # connect to database *dbname* "--file='#{@dump_filename}'", # read the dump "--single-transaction", # all or nothing (also runs COPY commands faster) host_argument, # the hostname to connect to (if any) port_argument, # the port to connect to (if any) username_argument # the username to connect as (if any) ].join(" ") end def switch_schema! log "Switching schemas..." sql = [ "BEGIN;", BackupRestore.move_tables_between_schemas_sql("public", "backup"), BackupRestore.move_tables_between_schemas_sql("restore", "public"), "COMMIT;" ].join("\n") @db_was_changed = true User.exec_sql(sql) end def migrate_database log "Migrating the database..." Discourse::Application.load_tasks ENV["VERSION"] = @current_version.to_s Rake::Task["db:migrate"].invoke end def reconnect_database log "Reconnecting to the database..." RailsMultisite::ConnectionManagement::establish_connection(db: @current_db) end def reload_site_settings log "Reloading site settings..." SiteSetting.refresh! end def extract_uploads if `tar --list --file #{@tar_filename} | grep 'uploads/'`.present? log "Extracting uploads..." FileUtils.cd(File.join(Rails.root, "public")) do `tar --extract --keep-newer-files --file #{@tar_filename} uploads/` end end end def rollback log "Trying to rollback..." if @db_was_changed && BackupRestore.can_rollback? log "Rolling back..." BackupRestore.move_tables_between_schemas("backup", "public") else log "There was no need to rollback" end end def notify_user if user = User.find_by(email: @user_info[:email]) log "Notifying '#{user.username}' of the end of the restore..." if @success SystemMessage.create_from_system_user(user, :restore_succeeded) else SystemMessage.create_from_system_user(user, :restore_failed, logs: @logs.join("\n")) end else log "Could not send notification to '#{@user_info[:username]}' (#{@user_info[:email]}), because the user does not exists..." end end def clean_up log "Cleaning stuff up..." remove_tmp_directory unpause_sidekiq disable_readonly_mode if Discourse.readonly_mode? mark_restore_as_not_running log "Finished!" end def remove_tmp_directory log "Removing tmp '#{@tmp_directory}' directory..." FileUtils.rm_rf(@tmp_directory) if Dir[@tmp_directory].present? rescue log "Something went wrong while removing the following tmp directory: #{@tmp_directory}" end def unpause_sidekiq log "Unpausing sidekiq..." Sidekiq.unpause! rescue log "Something went wrong while unpausing Sidekiq." end def disable_readonly_mode return if @readonly_mode_was_enabled log "Disabling readonly mode..." Discourse.disable_readonly_mode end def mark_restore_as_not_running log "Marking restore as finished..." BackupRestore.mark_as_not_running! end def ensure_directory_exists(directory) log "Making sure #{directory} exists..." FileUtils.mkdir_p(directory) end def log(message) puts(message) rescue nil publish_log(message) rescue nil save_log(message) end def publish_log(message) return unless @publish_to_message_bus data = { timestamp: Time.now, operation: "restore", message: message } MessageBus.publish(BackupRestore::LOGS_CHANNEL, data, user_ids: [@user_id]) end def save_log(message) @logs << "[#{Time.now}] #{message}" end end end