python-heatclient/heatclient/exc.py

#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

import sys

verbose = 0

try:
    import json
except ImportError:
    import simplejson as json


class BaseException(Exception):
    """An error occurred."""
    def __init__(self, message=None):
        self.message = message

    def __str__(self):
        return self.message or self.__class__.__doc__


class CommandError(BaseException):
    """Invalid usage of CLI."""


class InvalidEndpoint(BaseException):
    """The provided endpoint is invalid."""


class CommunicationError(BaseException):
    """Unable to communicate with server."""


class HTTPException(BaseException):
    """Base exception for all HTTP-derived exceptions."""
    code = 'N/A'

    def __init__(self, message=None):
        super(HTTPException, self).__init__(message)
        try:
            self.error = json.loads(message)
            if 'error' not in self.error:
                raise KeyError('Key "error" not exists')
        except KeyError:
            # NOTE(jianingy): If key 'error' happens not exist,
            # self.message becomes no sense. In this case, we
            # return doc of current exception class instead.
            self.error = {'error':
                          {'message': self.__class__.__doc__}}
        except Exception:
            self.error = {'error':
                          {'message': self.message or self.__class__.__doc__}}

    def __str__(self):
        message = self.error['error'].get('message', 'Internal Error')
        if verbose:
            traceback = self.error['error'].get('traceback', '')
            return 'ERROR: %s\n%s' % (message, traceback)
        else:
            return 'ERROR: %s' % message


class HTTPMultipleChoices(HTTPException):
    code = 300

    def __str__(self):
        self.details = ("Requested version of Heat API is not"
                        "available.")
        return "%s (HTTP %s) %s" % (self.__class__.__name__, self.code,
                                    self.details)


class BadRequest(HTTPException):
    """DEPRECATED."""
    code = 400


class HTTPBadRequest(BadRequest):
    pass


class Unauthorized(HTTPException):
    """DEPRECATED."""
    code = 401


class HTTPUnauthorized(Unauthorized):
    pass


class Forbidden(HTTPException):
    """DEPRECATED."""
    code = 403


class HTTPForbidden(Forbidden):
    pass


class NotFound(HTTPException):
    """DEPRECATED."""
    code = 404


class HTTPNotFound(NotFound):
    pass


class HTTPMethodNotAllowed(HTTPException):
    code = 405


class Conflict(HTTPException):
    """DEPRECATED."""
    code = 409


class HTTPConflict(Conflict):
    pass


class OverLimit(HTTPException):
    """DEPRECATED."""
    code = 413


class HTTPOverLimit(OverLimit):
    pass


class HTTPInternalServerError(HTTPException):
    code = 500


class HTTPNotImplemented(HTTPException):
    code = 501


class HTTPBadGateway(HTTPException):
    code = 502


class ServiceUnavailable(HTTPException):
    """DEPRECATED."""
    code = 503


class HTTPServiceUnavailable(ServiceUnavailable):
    pass


#NOTE(bcwaldon): Build a mapping of HTTP codes to corresponding exception
# classes
_code_map = {}
for obj_name in dir(sys.modules[__name__]):
    if obj_name.startswith('HTTP'):
        obj = getattr(sys.modules[__name__], obj_name)
        _code_map[obj.code] = obj


def from_response(response, body_iter):
    """Return an instance of an HTTPException based on httplib response."""
    cls = _code_map.get(response.status, HTTPException)
    body_str = ''.join([chunk for chunk in body_iter])
    return cls(body_str)


class NoTokenLookupException(Exception):
    """DEPRECATED."""
    pass


class EndpointNotFound(Exception):
    """DEPRECATED."""
    pass