RO/osm_ro/http_tools/errors.py

   1 # -*- coding: utf-8 -*-
   2 ##
   3 # Licensed under the Apache License, Version 2.0 (the "License"); you may
   4 # not use this file except in compliance with the License. You may obtain
   5 # a copy of the License at
   6 #
   7 #         http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  11 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  12 # License for the specific language governing permissions and limitations
  13 # under the License.
  14 ##
  15
  16 import logging
  17 from functools import wraps
  18
  19 import bottle
  20 import yaml
  21
  22 Bad_Request = 400
  23 Unauthorized = 401
  24 Not_Found = 404
  25 Forbidden = 403
  26 Method_Not_Allowed = 405
  27 Not_Acceptable = 406
  28 Request_Timeout = 408
  29 Conflict = 409
  30 Service_Unavailable = 503
  31 Internal_Server_Error = 500
  32
  33
  34 class HttpMappedError(Exception):
  35     """Base class for a new hierarchy that translate HTTP error codes
  36     to python exceptions
  37
  38     This class accepts an extra argument ``http_code`` (integer
  39     representing HTTP error codes).
  40     """
  41
  42     def __init__(self, message, http_code=Internal_Server_Error):
  43         Exception.__init__(self, message)
  44         self.http_code = http_code
  45
  46
  47 class ErrorHandler(object):
  48     """Defines a default strategy for handling HttpMappedError.
  49
  50     This class implements a wrapper (can also be used as decorator), that
  51     watches out for different exceptions and log them accordingly.
  52
  53     Arguments:
  54         logger(logging.Logger): logger object to be used to report errors
  55     """
  56     def __init__(self, logger=None):
  57         self.logger = logger or logging.getLogger('openmano.http')
  58
  59     def __call__(self, function):
  60         @wraps(function)
  61         def _wraped(*args, **kwargs):
  62             try:
  63                 return function(*args, **kwargs)
  64             except bottle.HTTPError:
  65                 raise
  66             except HttpMappedError as ex:
  67                 self.logger.error(
  68                     "%s error %s",
  69                     function.__name__, ex.http_code, exc_info=True)
  70                 bottle.abort(ex.http_code, str(ex))
  71             except yaml.YAMLError as ex:
  72                 self.logger.error(
  73                     "YAML error while trying to serialize/unserialize fields",
  74                     exc_info=True)
  75                 bottle.abort(Bad_Request, type(ex).__name__ + ": " + str(ex))
  76             except Exception as ex:
  77                 self.logger.error("Unexpected exception: ", exc_info=True)
  78                 bottle.abort(Internal_Server_Error,
  79                              type(ex).__name__ + ": " + str(ex))
  80
  81         return _wraped