# Copyright 2013-2016 DataStax, Inc.
#
# 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 logging
class NullHandler(logging.Handler):
def emit(self, record):
pass
logging.getLogger('cassandra').addHandler(NullHandler())
__version_info__ = (3, 2, 0, 'post0')
__version__ = '.'.join(map(str, __version_info__))
[docs]class ConsistencyLevel(object):
"""
Spcifies how many replicas must respond for an operation to be considered
a success. By default, ``ONE`` is used for all operations.
"""
ANY = 0
"""
Only requires that one replica receives the write *or* the coordinator
stores a hint to replay later. Valid only for writes.
"""
ONE = 1
"""
Only one replica needs to respond to consider the operation a success
"""
TWO = 2
"""
Two replicas must respond to consider the operation a success
"""
THREE = 3
"""
Three replicas must respond to consider the operation a success
"""
QUORUM = 4
"""
``ceil(RF/2)`` replicas must respond to consider the operation a success
"""
ALL = 5
"""
All replicas must respond to consider the operation a success
"""
LOCAL_QUORUM = 6
"""
Requires a quorum of replicas in the local datacenter
"""
EACH_QUORUM = 7
"""
Requires a quorum of replicas in each datacenter
"""
SERIAL = 8
"""
For conditional inserts/updates that utilize Cassandra's lightweight
transactions, this requires consensus among all replicas for the
modified data.
"""
LOCAL_SERIAL = 9
"""
Like :attr:`~ConsistencyLevel.SERIAL`, but only requires consensus
among replicas in the local datacenter.
"""
LOCAL_ONE = 10
"""
Sends a request only to replicas in the local datacenter and waits for
one response.
"""
ConsistencyLevel.value_to_name = {
ConsistencyLevel.ANY: 'ANY',
ConsistencyLevel.ONE: 'ONE',
ConsistencyLevel.TWO: 'TWO',
ConsistencyLevel.THREE: 'THREE',
ConsistencyLevel.QUORUM: 'QUORUM',
ConsistencyLevel.ALL: 'ALL',
ConsistencyLevel.LOCAL_QUORUM: 'LOCAL_QUORUM',
ConsistencyLevel.EACH_QUORUM: 'EACH_QUORUM',
ConsistencyLevel.SERIAL: 'SERIAL',
ConsistencyLevel.LOCAL_SERIAL: 'LOCAL_SERIAL',
ConsistencyLevel.LOCAL_ONE: 'LOCAL_ONE'
}
ConsistencyLevel.name_to_value = {
'ANY': ConsistencyLevel.ANY,
'ONE': ConsistencyLevel.ONE,
'TWO': ConsistencyLevel.TWO,
'THREE': ConsistencyLevel.THREE,
'QUORUM': ConsistencyLevel.QUORUM,
'ALL': ConsistencyLevel.ALL,
'LOCAL_QUORUM': ConsistencyLevel.LOCAL_QUORUM,
'EACH_QUORUM': ConsistencyLevel.EACH_QUORUM,
'SERIAL': ConsistencyLevel.SERIAL,
'LOCAL_SERIAL': ConsistencyLevel.LOCAL_SERIAL,
'LOCAL_ONE': ConsistencyLevel.LOCAL_ONE
}
def consistency_value_to_name(value):
return ConsistencyLevel.value_to_name[value] if value is not None else "Not Set"
class SchemaChangeType(object):
DROPPED = 'DROPPED'
CREATED = 'CREATED'
UPDATED = 'UPDATED'
class SchemaTargetType(object):
KEYSPACE = 'KEYSPACE'
TABLE = 'TABLE'
TYPE = 'TYPE'
FUNCTION = 'FUNCTION'
AGGREGATE = 'AGGREGATE'
class SignatureDescriptor(object):
def __init__(self, name, argument_types):
self.name = name
self.argument_types = argument_types
@property
def signature(self):
"""
function signature string in the form 'name([type0[,type1[...]]])'
can be used to uniquely identify overloaded function names within a keyspace
"""
return self.format_signature(self.name, self.argument_types)
@staticmethod
def format_signature(name, argument_types):
return "%s(%s)" % (name, ','.join(t for t in argument_types))
def __repr__(self):
return "%s(%s, %s)" % (self.__class__.__name__, self.name, self.argument_types)
[docs]class UserFunctionDescriptor(SignatureDescriptor):
"""
Describes a User function by name and argument signature
"""
name = None
"""
name of the function
"""
argument_types = None
"""
Ordered list of CQL argument type names comprising the type signature
"""
[docs]class UserAggregateDescriptor(SignatureDescriptor):
"""
Describes a User aggregate function by name and argument signature
"""
name = None
"""
name of the aggregate
"""
argument_types = None
"""
Ordered list of CQL argument type names comprising the type signature
"""
class DriverException(Exception):
pass
[docs]class Unavailable(DriverException):
"""
There were not enough live replicas to satisfy the requested consistency
level, so the coordinator node immediately failed the request without
forwarding it to any replicas.
"""
consistency = None
""" The requested :class:`ConsistencyLevel` """
required_replicas = None
""" The number of replicas that needed to be live to complete the operation """
alive_replicas = None
""" The number of replicas that were actually alive """
def __init__(self, summary_message, consistency=None, required_replicas=None, alive_replicas=None):
self.consistency = consistency
self.required_replicas = required_replicas
self.alive_replicas = alive_replicas
Exception.__init__(self, summary_message + ' info=' +
repr({'consistency': consistency_value_to_name(consistency),
'required_replicas': required_replicas,
'alive_replicas': alive_replicas}))
[docs]class Timeout(DriverException):
"""
Replicas failed to respond to the coordinator node before timing out.
"""
consistency = None
""" The requested :class:`ConsistencyLevel` """
required_responses = None
""" The number of required replica responses """
received_responses = None
"""
The number of replicas that responded before the coordinator timed out
the operation
"""
def __init__(self, summary_message, consistency=None, required_responses=None, received_responses=None):
self.consistency = consistency
self.required_responses = required_responses
self.received_responses = received_responses
Exception.__init__(self, summary_message + ' info=' +
repr({'consistency': consistency_value_to_name(consistency),
'required_responses': required_responses,
'received_responses': received_responses}))
[docs]class ReadTimeout(Timeout):
"""
A subclass of :exc:`Timeout` for read operations.
This indicates that the replicas failed to respond to the coordinator
node before the configured timeout. This timeout is configured in
``cassandra.yaml`` with the ``read_request_timeout_in_ms``
and ``range_request_timeout_in_ms`` options.
"""
data_retrieved = None
"""
A boolean indicating whether the requested data was retrieved
by the coordinator from any replicas before it timed out the
operation
"""
def __init__(self, message, data_retrieved=None, **kwargs):
Timeout.__init__(self, message, **kwargs)
self.data_retrieved = data_retrieved
[docs]class WriteTimeout(Timeout):
"""
A subclass of :exc:`Timeout` for write operations.
This indicates that the replicas failed to respond to the coordinator
node before the configured timeout. This timeout is configured in
``cassandra.yaml`` with the ``write_request_timeout_in_ms``
option.
"""
write_type = None
"""
The type of write operation, enum on :class:`~cassandra.policies.WriteType`
"""
def __init__(self, message, write_type=None, **kwargs):
Timeout.__init__(self, message, **kwargs)
self.write_type = write_type
class CoordinationFailure(DriverException):
"""
Replicas sent a failure to the coordinator.
"""
consistency = None
""" The requested :class:`ConsistencyLevel` """
required_responses = None
""" The number of required replica responses """
received_responses = None
"""
The number of replicas that responded before the coordinator timed out
the operation
"""
failures = None
"""
The number of replicas that sent a failure message
"""
def __init__(self, summary_message, consistency=None, required_responses=None, received_responses=None, failures=None):
self.consistency = consistency
self.required_responses = required_responses
self.received_responses = received_responses
self.failures = failures
Exception.__init__(self, summary_message + ' info=' +
repr({'consistency': consistency_value_to_name(consistency),
'required_responses': required_responses,
'received_responses': received_responses,
'failures': failures}))
[docs]class ReadFailure(CoordinationFailure):
"""
A subclass of :exc:`CoordinationFailure` for read operations.
This indicates that the replicas sent a failure message to the coordinator.
"""
data_retrieved = None
"""
A boolean indicating whether the requested data was retrieved
by the coordinator from any replicas before it timed out the
operation
"""
def __init__(self, message, data_retrieved=None, **kwargs):
CoordinationFailure.__init__(self, message, **kwargs)
self.data_retrieved = data_retrieved
[docs]class WriteFailure(CoordinationFailure):
"""
A subclass of :exc:`CoordinationFailure` for write operations.
This indicates that the replicas sent a failure message to the coordinator.
"""
write_type = None
"""
The type of write operation, enum on :class:`~cassandra.policies.WriteType`
"""
def __init__(self, message, write_type=None, **kwargs):
CoordinationFailure.__init__(self, message, **kwargs)
self.write_type = write_type
[docs]class FunctionFailure(DriverException):
"""
User Defined Function failed during execution
"""
keyspace = None
"""
Keyspace of the function
"""
function = None
"""
Name of the function
"""
arg_types = None
"""
List of argument type names of the function
"""
def __init__(self, summary_message, keyspace, function, arg_types):
self.keyspace = keyspace
self.function = function
self.arg_types = arg_types
Exception.__init__(self, summary_message)
[docs]class AlreadyExists(DriverException):
"""
An attempt was made to create a keyspace or table that already exists.
"""
keyspace = None
"""
The name of the keyspace that already exists, or, if an attempt was
made to create a new table, the keyspace that the table is in.
"""
table = None
"""
The name of the table that already exists, or, if an attempt was
make to create a keyspace, :const:`None`.
"""
def __init__(self, keyspace=None, table=None):
if table:
message = "Table '%s.%s' already exists" % (keyspace, table)
else:
message = "Keyspace '%s' already exists" % (keyspace,)
Exception.__init__(self, message)
self.keyspace = keyspace
self.table = table
[docs]class InvalidRequest(DriverException):
"""
A query was made that was invalid for some reason, such as trying to set
the keyspace for a connection to a nonexistent keyspace.
"""
pass
[docs]class Unauthorized(DriverException):
"""
The current user is not authorized to perfom the requested operation.
"""
pass
[docs]class AuthenticationFailed(DriverException):
"""
Failed to authenticate.
"""
pass
[docs]class OperationTimedOut(DriverException):
"""
The operation took longer than the specified (client-side) timeout
to complete. This is not an error generated by Cassandra, only
the driver.
"""
errors = None
"""
A dict of errors keyed by the :class:`~.Host` against which they occurred.
"""
last_host = None
"""
The last :class:`~.Host` this operation was attempted against.
"""
def __init__(self, errors=None, last_host=None):
self.errors = errors
self.last_host = last_host
message = "errors=%s, last_host=%s" % (self.errors, self.last_host)
Exception.__init__(self, message)
class UnsupportedOperation(DriverException):
"""
An attempt was made to use a feature that is not supported by the
selected protocol version. See :attr:`Cluster.protocol_version`
for more details.
"""
pass