浅析Python 责任链设计模式

"""
责任链模式
"""
from abc import abstractmethod, ABCMeta


class Handler(metaclass=ABCMeta):
  @abstractmethod
  def handler_leave(self, day):
    pass


# 总经理审批
class GenaralHandler(Handler):
  def handler_leave(self, day):
    if day <= 10:
      print('总经理批准你%s天假，好好去玩吧' % day)
    else:
      print('你干脆辞职了吧')


# 部门经理审批
class DepartmentHandler(Handler):
  def __init__(self):
    self.upHandler = GenaralHandler()

  def handler_leave(self, day):
    if day <= 7:
      print('部门经理批准你%s天假，好好去玩吧' % day)
    else:
      print('你请假超过七天，我无权受理，你去找总经理吧')
      self.upHandler.handler_leave(day)


# 项目主管审批
class ProjectHandler(Handler):
  def __init__(self):
    self.upHandler = DepartmentHandler()

  def handler_leave(self, day):
    if day <= 3:
      print('项目主管批准你%s天假，好好去玩吧' % day)
    else:
      print('你请假超过三天，我无权受理，你去找部门经理审批吧')
      self.upHandler.handler_leave(day)


if __name__ == '__main__':
  h = ProjectHandler();
  h.handler_leave(5)