openproject/app/models/queries/base_order.rb

#-- encoding: UTF-8

#-- copyright
# OpenProject is a project management system.
# Copyright (C) 2012-2018 the OpenProject Foundation (OPF)
#
# 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.
#++

class Queries::BaseOrder
  include ActiveModel::Validations

  VALID_DIRECTIONS = %i(asc desc).freeze

  def self.i18n_scope
    :activerecord
  end

  validates :direction, inclusion: { in: VALID_DIRECTIONS }

  class_attribute :model
  attr_accessor :direction,
                :attribute

  def initialize(attribute)
    self.attribute = attribute
  end

  def self.key
    raise NotImplementedError
  end

  def scope
    scope = order
    scope = scope.joins(joins) if joins
    scope = scope.left_outer_joins(left_outer_joins) if left_outer_joins
    scope
  end

  def name
    attribute
  end

  private

  def order
    model.order(name => direction)
  end

  def joins
    nil
  end

  def left_outer_joins
    nil
  end

  def with_raise_on_invalid
    if VALID_DIRECTIONS.include?(direction)
      yield
    else
      raise ArgumentError, "Only one of #{VALID_DIRECTIONS} allowed. #{direction} is provided."
    end
  end
end