openproject/app/services/concerns/with_reversible_state.rb

#-- encoding: UTF-8

#-- copyright
# OpenProject is an open source project management software.
# Copyright (C) 2012-2020 the OpenProject GmbH
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License version 3.
#
# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
# Copyright (C) 2006-2017 Jean-Philippe Lang
# Copyright (C) 2010-2013 the ChiliProject Team
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
# See docs/COPYRIGHT.rdoc for more details.
#++

module WithReversibleState
  extend ActiveSupport::Concern

  included do
    attr_reader :state
    around_call :assign_state

    ##
    # Reuse or append state to the service
    def with_state(state = {})
      @state = ::Shared::ServiceState.build(state)
      self
    end

    ##
    # Access to the shared service state
    def state
      @state ||= ::Shared::ServiceState.build
    end

    ##
    # Rollback changes made
    def rollback
      # Nothing to do by default
    end

    ##
    # Assign state to the service result
    def assign_state
      yield.tap do |call|
        state.called!(self)
        call.state = state
      end
    end
  end
end