src/postorius/middleware.py

   1 # -*- coding: utf-8 -*-
   2 # Copyright (C) 2015-2022 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     def __init__(self, get_response=None):
  39         self.get_response = get_response
  40
  41     def __call__(self, request):
  42         return self.get_response(request)
  43
  44     def process_exception(self, request, exception):
  45         if isinstance(exception, (MailmanApiError, MailmanConnectionError)):
  46             logger.exception('Mailman REST API not available')
  47             return utils.render_api_error(request)
  48         elif isinstance(exception, HTTPError):
  49             logger.exception('Un-handled exception: %s', str(exception))
  50             return utils.render_client_error(request, exception)
  51
  52
  53 class APICountingMiddleware:
  54     """Counts the total number of API calls made to Core and prints summary.
  55
  56     It hooks into mailmanclient's hooking mechanism, facilitated by
  57     ``django_mailman3.lib.mailman.mailmanclient_request_hook``. It stores the
  58     parameter of each API call made in `self.api_call_counter()` and prints it
  59     *before* returning the response in `__call__`.
  60
  61     It hooks up ``_trace_api_calls()`` method into the Hooks API. Even if the
  62     hooking happens multiple times, it is only added once since it
  63     deduplicates the hooks.
  64
  65     Output looks something like:
  66
  67     DEBUG: =======================
  68     DEBUG: Handle reqsponse for /postorius/lists/mylist.lists.araj.me/settings/
  69     DEBUG: View function was postorius.views.list.list_settings
  70     DEBUG: 4 calls to API
  71     DEBUG: [GET] http://localhost:8001/3.1/lists/mylist.lists.araj.me with None
  72     DEBUG: [snip]
  73     DEBUG: ======================
  74
  75     Note: If you don't see the output on console, check the 'postorius' logger
  76     settings and make sure that it has `console` handler and level is set to
  77     'DEBUG'.
  78
  79     """
  80
  81     def __init__(self, get_response=None):
  82         self.get_response = get_response
  83         mailman.mailmanclient_request_hook(self._trace_api_calls)
  84         self.api_call_counter = []
  85         self.view_func = ''
  86
  87     def __call__(self, request):
  88         self.request = request
  89         response = self.get_response(request)
  90         logger.debug('=======================')
  91         logger.debug('Handle reqsponse for %s', request.path)
  92         logger.debug('View function was %s', self.view_func)
  93         logger.debug('%s calls to API', len(self.api_call_counter))
  94         for each in self.api_call_counter:
  95             logger.debug(
  96                 '[%s] %s with %s',
  97                 each.get('method'),
  98                 each.get('url'),
  99                 each.get('data'),
 100             )
 101         logger.debug('=======================')
 102         self.api_call_counter = []
 103         return response
 104
 105     def _trace_api_calls(self, params):
 106         """Hook that adds all the call parameters to self.api_call_counter.
 107
 108         :param params: List of request params from mailmanclient.
 109         """
 110         self.api_call_counter.append(params)
 111         return params
 112
 113     def process_view(self, request, view_func, view_args, view_kwars):
 114         """Get a pointer to view function object."""
 115         self.view_func = '{}.{}'.format(
 116             view_func.__module__, view_func.__name__
 117         )