python-novaclient/novaclient/exceptions.py
2011-09-26 12:28:43 -07:00

121 lines
2.9 KiB
Python

# Copyright 2010 Jacob Kaplan-Moss
"""
Exception definitions.
"""
class CommandError(Exception):
pass
class AuthorizationFailure(Exception):
pass
class NoTokenLookupException(Exception):
"""This form of authentication does not support looking up
endpoints from an existing token."""
pass
class EndpointNotFound(Exception):
"""Could not find Service or Region in Service Catalog."""
pass
class ClientException(Exception):
"""
The base exception class for all exceptions this library raises.
"""
def __init__(self, code, message=None, details=None):
self.code = code
self.message = message or self.__class__.message
self.details = details
def __str__(self):
return "%s (HTTP %s)" % (self.message, self.code)
class BadRequest(ClientException):
"""
HTTP 400 - Bad request: you sent some malformed data.
"""
http_status = 400
message = "Bad request"
class Unauthorized(ClientException):
"""
HTTP 401 - Unauthorized: bad credentials.
"""
http_status = 401
message = "Unauthorized"
class Forbidden(ClientException):
"""
HTTP 403 - Forbidden: your credentials don't give you access to this
resource.
"""
http_status = 403
message = "Forbidden"
class NotFound(ClientException):
"""
HTTP 404 - Not found
"""
http_status = 404
message = "Not found"
class OverLimit(ClientException):
"""
HTTP 413 - Over limit: you're over the API limits for this time period.
"""
http_status = 413
message = "Over limit"
# NotImplemented is a python keyword.
class HTTPNotImplemented(ClientException):
"""
HTTP 501 - Not Implemented: the server does not support this operation.
"""
http_status = 501
message = "Not Implemented"
# In Python 2.4 Exception is old-style and thus doesn't have a __subclasses__()
# so we can do this:
# _code_map = dict((c.http_status, c)
# for c in ClientException.__subclasses__())
#
# Instead, we have to hardcode it:
_code_map = dict((c.http_status, c) for c in [BadRequest, Unauthorized,
Forbidden, NotFound, OverLimit, HTTPNotImplemented])
def from_response(response, body):
"""
Return an instance of an ClientException or subclass
based on an httplib2 response.
Usage::
resp, body = http.request(...)
if resp.status != 200:
raise exception_from_response(resp, body)
"""
cls = _code_map.get(response.status, ClientException)
if body:
message = "n/a"
details = "n/a"
if hasattr(body, 'keys'):
error = body[body.keys()[0]]
message = error.get('message', None)
details = error.get('details', None)
return cls(code=response.status, message=message, details=details)
else:
return cls(code=response.status)