src/postorius/middleware.py

   1 # -*- coding: utf-8 -*-
   2 # Copyright (C) 2015-2021 by the Free Software Foundation, Inc.
   3 #
   4 # This file is part of Postorius.
   5 #
   6 # Postorius is free software: you can redistribute it and/or modify it under
   7 # the terms of the GNU General Public License as published by the Free
   8 # Software Foundation, either version 3 of the License, or (at your option)
   9 # any later version.
  10 #
  11 # Postorius is distributed in the hope that it will be useful, but WITHOUT
  12 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 # FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14 # more details.
  15 #
  16 # You should have received a copy of the GNU General Public License along with
  17 # Postorius.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 import logging
  20 from urllib.error import HTTPError
  21
  22 from django_mailman3.lib import mailman
  23 from mailmanclient import MailmanConnectionError
  24
  25 from postorius import utils
  26 from postorius.models import MailmanApiError
  27
  28
  29 logger = logging.getLogger('postorius')
  30
  31
  32 __all__ = [
  33     'PostoriusMiddleware',
  34 ]
  35
  36
  37 class PostoriusMiddleware(object):
  38
  39     def __init__(self, get_response=None):
  40         self.get_response = get_response
  41
  42     def __call__(self, request):
  43         return self.get_response(request)
  44
  45     def process_exception(self, request, exception):
  46         if isinstance(exception, (MailmanApiError, MailmanConnectionError)):
  47             logger.exception('Mailman REST API not available')
  48             return utils.render_api_error(request)
  49         elif isinstance(exception, HTTPError):
  50             logger.exception('Un-handled exception: %s', str(exception))
  51             return utils.render_client_error(request, exception)
  52
  53
  54 class APICountingMiddleware:
  55     """Counts the total number of API calls made to Core and prints summary.
  56
  57     It hooks into mailmanclient's hooking mechanism, facilitated by
  58     ``django_mailman3.lib.mailman.mailmanclient_request_hook``. It stores the
  59     parameter of each API call made in `self.api_call_counter()` and prints it
  60     *before* returning the response in `__call__`.
  61
  62     It hooks up ``_trace_api_calls()`` method into the Hooks API. Even if the
  63     hooking happens multiple times, it is only added once since it
  64     deduplicates the hooks.
  65
  66     Output looks something like:
  67
  68     DEBUG: =======================
  69     DEBUG: Handle reqsponse for /postorius/lists/mylist.lists.araj.me/settings/
  70     DEBUG: View function was postorius.views.list.list_settings
  71     DEBUG: 4 calls to API
  72     DEBUG: [GET] http://localhost:8001/3.1/lists/mylist.lists.araj.me with None
  73     DEBUG: [snip]
  74     DEBUG: ======================
  75
  76     Note: If you don't see the output on console, check the 'postorius' logger
  77     settings and make sure that it has `console` handler and level is set to
  78     'DEBUG'.
  79
  80     """
  81
  82     def __init__(self, get_response=None):
  83         self.get_response = get_response
  84         mailman.mailmanclient_request_hook(self._trace_api_calls)
  85         self.api_call_counter = []
  86         self.view_func = ''
  87
  88     def __call__(self, request):
  89         self.request = request
  90         response = self.get_response(request)
  91         logger.debug('=======================')
  92         logger.debug('Handle reqsponse for %s', request.path)
  93         logger.debug('View function was %s', self.view_func)
  94         logger.debug('%s calls to API', len(self.api_call_counter))
  95         for each in self.api_call_counter:
  96             logger.debug('[%s] %s with %s',
  97                          each.get('method'), each.get('url'), each.get('data'))
  98         logger.debug('=======================')
  99         return response
 100
 101     def _trace_api_calls(self, params):
 102         """Hook that adds all the call parameters to self.api_call_counter.
 103
 104         :param params: List of request params from mailmanclient.
 105         """
 106         self.api_call_counter.append(params)
 107         return params
 108
 109     def process_view(self, request, view_func, view_args, view_kwars):
 110         """Get a pointer to view function object."""
 111         self.view_func = '{}.{}'.format(
 112             view_func.__module__, view_func.__name__)