Source code for pywbem._exceptions

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"""
The following exceptions are pywbem specific exceptions that can be raised at
the WBEM client library API.
"""

import six
from ._cim_constants import _statuscode2name, _statuscode2string

# This module is meant to be safe for 'import *'.

__all__ = ['Error', 'ConnectionError', 'AuthError', 'HTTPError', 'TimeoutError',
           'VersionError', 'ParseError', 'CIMXMLParseError', 'XMLParseError',
           'HeaderParseError', 'CIMError', 'ModelError',
           '_RequestExceptionMixin', '_ResponseExceptionMixin']


[docs]class _RequestExceptionMixin(object): # pylint: disable=too-few-public-methods """ An internal mixin class for pywbem specific exceptions that provides the ability to store the CIM-XML request string in the exception. *New in pywbem 1.0.* Derived classes using this mixin class need to specify it before the base error class. """ def __init__(self, *args, **kwargs): """ Parameters: *args : Any other positional arguments are passed on to the next superclass. **kwargs : Any other keyword arguments are passed on to the next superclass. request_data (:term:`string`): CIM-XML request string. Omitted or `None` means the exception does not store a CIM-XML request. Must be specified as a keyword argument; if specified it will be removed from the keyword arguments that are passed on. """ if 'request_data' in kwargs: request_data = kwargs['request_data'] del kwargs['request_data'] else: request_data = None self.request_data = request_data super(_RequestExceptionMixin, self).__init__(*args, **kwargs) @property def request_data(self): """ :term:`string`: CIM-XML request string (settable). `None` if the exception does not store a CIM-XML request. """ return self._request_data @request_data.setter def request_data(self, request_data): """Setter method; for a description see the getter method.""" self._request_data = request_data
[docs]class _ResponseExceptionMixin(object): # pylint: disable=too-few-public-methods """ Mixin class into pywbem specific exceptions that provides the ability to store the CIM-XML response string in the exception. *New in pywbem 1.0.* Derived classes using this mixin class need to specify it before the base error class. """ def __init__(self, *args, **kwargs): """ Parameters: *args : Any other positional arguments are passed on to the next superclass. **kwargs : Any other keyword arguments are passed on to the next superclass. response_data (:term:`string`): CIM-XML response string. Omitted or `None` means the exception does not store a CIM-XML response. Must be specified as a keyword argument; if specified it will be removed from the keyword arguments that are passed on. """ if 'response_data' in kwargs: response_data = kwargs['response_data'] del kwargs['response_data'] else: response_data = None self.response_data = response_data super(_ResponseExceptionMixin, self).__init__(*args, **kwargs) @property def response_data(self): """ :term:`string`: CIM-XML response string (settable). `None` if the exception does not store a CIM-XML response. """ return self._response_data @response_data.setter def response_data(self, response_data): """Setter method; for a description see the getter method.""" self._response_data = response_data
[docs]class Error(Exception): """ Abstract base class for pywbem specific exceptions. """ def __init__(self, *args, **kwargs): """ Parameters: *args : Any other positional arguments are passed to :exc:`py:Exception`. conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. Omitted or `None` if the error did not happen in context of any connection, or if the connection context was not known. Must be specified as a keyword argument. """ if 'conn_id' in kwargs: conn_id = kwargs['conn_id'] del kwargs['conn_id'] else: conn_id = None self._conn_id = conn_id # The Python Exception class cannot be initialized with keyword args assert not kwargs, str(kwargs) super(Error, self).__init__(*args) @property def conn_id(self): """ :term:`connection id`: Connection ID of the connection in whose context the error happened. `None` if the error did not happen in context of any connection, or if the connection context was not known. """ return self._conn_id @property def conn_str(self): """ :term:`unicode string`: String that identifies the connection in exception messages. """ ret_str = "Connection id: {0}".format(self.conn_id) return ret_str
[docs]class ConnectionError(Error): # pylint: disable=redefined-builtin """ This exception indicates a problem with the connection to the WBEM server. A retry may or may not succeed. Derived from :exc:`~pywbem.Error`. """ def __init__(self, message, conn_id=None): """ Parameters: message (:term:`string`): Error message (will be put into `args[0]`). conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. Omitted or `None` if the error did not happen in context of any connection, or if the connection context was not known. :ivar args: A tuple (message, ) set from the corresponding init arguments. """ assert message is None or isinstance(message, six.string_types), \ str(type(message)) super(ConnectionError, self).__init__(message, conn_id=conn_id)
[docs]class AuthError(Error): """ This exception indicates an authentication error with the WBEM server, either during TLS/SSL handshake, or during HTTP-level authentication. Derived from :exc:`~pywbem.Error`. """ def __init__(self, message, conn_id=None): """ Parameters: message (:term:`string`): Error message (will be put into `args[0]`). conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. Omitted or `None` if the error did not happen in context of any connection, or if the connection context was not known. :ivar args: A tuple (message, ) set from the corresponding init arguments. """ assert message is None or isinstance(message, six.string_types), \ str(type(message)) super(AuthError, self).__init__(message, conn_id=conn_id)
[docs]class HTTPError(_RequestExceptionMixin, _ResponseExceptionMixin, Error): """ This exception indicates that the WBEM server returned an HTTP response with a bad HTTP status code. Derived from :exc:`~pywbem.Error`. The `args` instance variable is a `tuple (status, reason, cimerror, cimdetails)`. The `message` instance variable is not set. Occurrence of this exception nearly always indicates an issue with the WBEM server. """ def __init__(self, status, reason, cimerror=None, cimdetails=None, conn_id=None, request_data=None, response_data=None): """ Parameters: status (:term:`integer`): HTTP status code (e.g. 500). reason (:term:`string`): HTTP reason phrase (e.g. "Internal Server Error"). cimerror (:term:`string`): Value of the `CIMError` HTTP header field, if present. `None`, otherwise. cimdetails (dict): Dictionary with CIMOM-specific header fields with details about the situation reported in the `CIMError` header field. * Key: header field name (e.g. `PGErrorDetail`) * Value: header field value (i.e. text message) Passing `None` will result in an empty dictionary. conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. `None` if the error did not happen in context of any connection, or if the connection context was not known. request_data (:term:`string`): CIM-XML request string. `None` means the exception does not store a CIM-XML request. response_data (:term:`string`): CIM-XML response string. `None` means the exception does not store a CIM-XML response. :ivar args: A tuple (status, reason, cimerror, cimdetails) set from the corresponding init arguments. """ if cimdetails is None: cimdetails = {} super(HTTPError, self).__init__( status, reason, cimerror, cimdetails, conn_id=conn_id, request_data=request_data, response_data=response_data) @property def status(self): """ :term:`integer`: HTTP status code. Example: 500 See :term:`RFC2616` for a list of HTTP status codes and reason phrases. """ # Note: The reporting of unsubscriptable-object seems to be a false # positive in Pylint, see https://github.com/PyCQA/pylint/issues/1498 return self.args[0] # pylint: disable=unsubscriptable-object @property def reason(self): """ :term:`string`: HTTP reason phrase. Example: "Internal Server Error" See :term:`RFC2616` for a list of HTTP status codes and reason phrases. """ return self.args[1] # pylint: disable=unsubscriptable-object @property def cimerror(self): """ :term:`string`: Value of `CIMError` HTTP header field in response, if present. `None`, otherwise. See :term:`DSP0200` for a list of values. """ return self.args[2] # pylint: disable=unsubscriptable-object @property def cimdetails(self): """ dict: CIMOM-specific details on the situation reported in the `CIMError` header field. The value is a dictionary with: * Key: header field name (e.g. `PGErrorDetail`). * Value: header field value. """ return self.args[3] # pylint: disable=unsubscriptable-object def __str__(self): ret_str = "{0} ({1})".format(self.status, self.reason) if self.cimerror is not None: ret_str += ", CIMError: {0}".format(self.cimerror) for key in self.cimdetails: ret_str += ", {0}: {1}".format(key, self.cimdetails[key]) return ret_str
[docs]class TimeoutError(Error): # pylint: disable=redefined-builtin """ This exception indicates that the client timed out waiting for the WBEM server. Derived from :exc:`~pywbem.Error`. """ def __init__(self, message, conn_id=None): """ Parameters: message (:term:`string`): Error message (will be put into `args[0]`). conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. Omitted or `None` if the error did not happen in context of any connection, or if the connection context was not known. :ivar args: A tuple (message, ) set from the corresponding init arguments. """ assert message is None or isinstance(message, six.string_types), \ str(type(message)) super(TimeoutError, self).__init__(message, conn_id=conn_id)
[docs]class ParseError(_RequestExceptionMixin, _ResponseExceptionMixin, Error): """ This exception indicates a parsing error with the CIM-XML operation response the pywbem client received, or with the CIM-XML indication request the pywbem listener received. Derived from :exc:`~pywbem.Error`. The CIM-XML response data is part of the `str()` representation of the exception. This exception is a base class for more specific exceptions: * :exc:`~pywbem.CIMXMLParseError` - Issue at the CIM-XML level (e.g. NAME attribute missing on CLASS element) * :exc:`~pywbem.XMLParseError` - Issue at the XML level (e.g. ill-formed XML) * :exc:`~pywbem.HeaderParseError` - Issue with HTTP headers (e.g. invalid content-type header) Occurrence of this exception nearly always indicates an issue with the WBEM server. """ def __init__(self, message, conn_id=None, request_data=None, response_data=None): """ Parameters: message (:term:`string`): Error message (will be put into `args[0]`). conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. `None` if the error did not happen in context of any connection, or if the connection context was not known. request_data (:term:`string`): CIM-XML request string. `None` means the exception does not store a CIM-XML request. response_data (:term:`string`): CIM-XML response string. `None` means the exception does not store a CIM-XML response. :ivar args: A tuple (message, ) set from the corresponding init argument. """ assert message is None or isinstance(message, six.string_types), \ str(type(message)) super(ParseError, self).__init__( message, conn_id=conn_id, request_data=request_data, response_data=response_data) def __str__(self): error_str = super(ParseError, self).__str__() ret_str = "{0}\nCIM-XML response: {1}". \ format(error_str, self.response_data) return ret_str
[docs]class CIMXMLParseError(ParseError): """ This exception indicates a specific kind of :exc:`~pywbem.ParseError` that is an issue at the CIM-XML level. Example: 'NAME' attribute missing on 'CLASS' element. Occurrence of this exception nearly always indicates an issue with the WBEM server. """ pass
[docs]class XMLParseError(ParseError): """ This exception indicates a specific kind of :exc:`~pywbem.ParseError` that is an issue at the XML level. Example: Ill-formed XML. Occurrence of this exception nearly always indicates an issue with the WBEM server. """ pass
[docs]class HeaderParseError(ParseError): """ This exception indicates a specific kind of :exc:`~pywbem.ParseError` that is an issue with an HTTP header. Example: Invalid content-type. Occurrence of this exception nearly always indicates an issue with the WBEM server. """ pass
class VersionError(Error): """ This exception indicates an unsupported CIM, DTD or protocol version with the CIM-XML response returned by the WBEM server, or in the CIM-XML request sent by the WBEM listener. Derived from :exc:`~pywbem.Error`. """ def __init__(self, message, conn_id=None): """ Parameters: message (:term:`string`): Error message (will be put into `args[0]`). conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. Omitted or `None` if the error did not happen in context of any connection, or if the connection context was not known. :ivar args: A tuple (message, ) set from the corresponding init argument. """ assert message is None or isinstance(message, six.string_types), \ str(type(message)) super(VersionError, self).__init__(message, conn_id=conn_id)
[docs]class CIMError(_RequestExceptionMixin, Error): """ This exception indicates that the WBEM server returned an error response with a CIM status code. Derived from :exc:`~pywbem.Error`. Accessing the CIM status code of a :class:`CIMError` object: In Python 2, any :exc:`~py:exceptions.Exception` object can be accessed by index and slice and will delegate such access to its :attr:`~py:exceptions.BaseException.args` instance variable. In Python 3, that ability has been removed. In pywbem 0.9, the :attr:`~pywbem.CIMError.status_code` and :attr:`~pywbem.CIMError.status_description` properties were added. Therefore, the following approach is not recommended, because it does not work on Python 3:: except CIMError as exc: status_code = exc[0] The following approach works for pywbem 0.7 or newer:: except CIMError as exc: status_code = exc.args[0] The following approach is recommended when using pywbem 0.9 or newer:: except CIMError as exc: status_code = exc.status_code """ # pylint: disable=super-init-not-called def __init__(self, status_code, status_description=None, instances=None, conn_id=None, request_data=None): """ Parameters: status_code (:term:`integer`): Numeric CIM status code. status_description (:term:`string`): CIM status description text returned by the server, representing a human readable message describing the error. `None`, if the server did not return a description text. instances (list of :class:`~pywbem.CIMInstance`): List of CIM instances returned by the WBEM server in the error response, that provide more details on the error. `None` if there are no such instances. conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. `None` if the error did not happen in context of any connection, or if the connection context was not known. request_data (:term:`string`): CIM-XML request string. `None` means the exception does not store a CIM-XML request. :ivar args: A tuple (status_code, status_description, instances) set from the corresponding init arguments. """ super(CIMError, self).__init__( status_code, status_description, instances, conn_id=conn_id, request_data=request_data) @property def status_code(self): """ :term:`integer`: Numeric CIM status code. *New in pywbem 0.9.* Example: 5 See :ref:`CIM status codes` for constants defining the numeric CIM status code values.""" return self.args[0] # pylint: disable=unsubscriptable-object @property def status_code_name(self): """ :term:`string`: Symbolic name of the CIM status code. Example: "CIM_ERR_INVALID_CLASS" *New in pywbem 0.9.* If the CIM status code is invalid, the string "Invalid status code <status_code>" is returned.""" return _statuscode2name(self.status_code) @property def status_description(self): """ :term:`string`: CIM status description text returned by the server, representing a human readable message describing the error. *New in pywbem 0.9.* Example: "The specified class does not exist." If the server did not return a description, a short default text for the CIM status code is returned. If the CIM status code is invalid, the string "Invalid status code <status_code>" is returned. """ desc = self.args[1] # pylint: disable=unsubscriptable-object return desc or _statuscode2string(self.status_code) @property def instances(self): """ List of :class:`~pywbem.CIMInstance`: CIM instances returned by the WBEM server in the error response, that provide more details on the error. *New in pywbem 0.13.* `None` if there are no such instances. """ return self.args[2] # pylint: disable=unsubscriptable-object def __str__(self): inst_str = " ({0} instances)".format(len(self.instances)) \ if self.instances else "" ret_str = "{0} ({1}): {2}{3}".format( self.status_code, self.status_code_name, self.status_description, inst_str) return ret_str
[docs]class ModelError(Error): """ This exception indicates an error with the model implemented by the WBEM server, that was detected by the pywbem client. Examples are mismatches in data types of CIM elements (properties, methods, parameters) between classes and instances, CIM elements that appear in instances without being declared in classes, or violations of requirements defined in advertised management profiles. Derived from :exc:`~pywbem.Error`. """ def __init__(self, message, conn_id=None): """ Parameters: message (:term:`string`): Error message (will be put into `args[0]`). conn_id (:term:`connection id`): Connection ID of the connection in whose context the error happened. Omitted or `None` if the error did not happen in context of any connection, or if the connection context was not known. :ivar args: A tuple (message, ) set from the corresponding init argument. """ assert message is None or isinstance(message, six.string_types), \ str(type(message)) super(ModelError, self).__init__(message, conn_id=conn_id)