src/mailman/interfaces/pipeline.py

   1 # Copyright (C) 2008-2023 by the Free Software Foundation, Inc.
   2 #
   3 # This file is part of GNU Mailman.
   4 #
   5 # GNU Mailman is free software: you can redistribute it and/or modify it under
   6 # the terms of the GNU General Public License as published by the Free
   7 # Software Foundation, either version 3 of the License, or (at your option)
   8 # any later version.
   9 #
  10 # GNU Mailman is distributed in the hope that it will be useful, but WITHOUT
  11 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12 # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13 # more details.
  14 #
  15 # You should have received a copy of the GNU General Public License along with
  16 # GNU Mailman.  If not, see <https://www.gnu.org/licenses/>.
  17
  18 """Interface for describing pipelines."""
  19
  20 from mailman.core.i18n import _, format_reasons
  21 from public import public
  22 from zope.interface import Attribute, Interface
  23
  24
  25 NL = '\n'
  26
  27
  28 # These are thrown but they aren't exceptions so don't inherit from
  29 # mailman.interfaces.errors.MailmanError.  Python requires that they inherit
  30 # from BaseException.
  31 @public
  32 class DiscardMessage(BaseException):
  33     """The message can be discarded with no further action"""
  34
  35     def __init__(self, message=None):
  36         self.message = message
  37
  38     def __str__(self):
  39         return self.message
  40
  41
  42 @public
  43 class RejectMessage(BaseException):
  44     """The message will be bounced back to the sender"""
  45
  46     def __init__(self, message=None, reasons=None, substitutions=None):
  47         self.message = message
  48         self.reasons = reasons
  49         self.substitutions = ({} if substitutions is None else substitutions)
  50
  51     def __str__(self):
  52         if self.message is None:
  53             return _('[No details are available]')
  54         reasons = (_('[No reasons given]')
  55                    if self.reasons is None
  56                    else NL.join(format_reasons(self.reasons)))
  57         substitutions = self.substitutions.copy()
  58         substitutions['reasons'] = reasons
  59         return _(self.message, substitutions)
  60
  61
  62 @public
  63 class IPipeline(Interface):
  64     """A pipeline of handlers."""
  65
  66     name = Attribute('Pipeline name; must be unique.')
  67     description = Attribute('A brief description of this pipeline.')
  68
  69     def __iter__():
  70         """Iterate over all the handlers in this pipeline."""