Files
deb-python-cassandra-driver/cassandra/decoder.py
2014-03-19 17:14:11 -05:00

867 lines
24 KiB
Python

import logging
import socket
from uuid import UUID
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO # ignore flake8 warning: # NOQA
from cassandra import (Unavailable, WriteTimeout, ReadTimeout,
AlreadyExists, InvalidRequest, Unauthorized,
UnsupportedOperation)
from cassandra.marshal import (int32_pack, int32_unpack, uint16_pack, uint16_unpack,
int8_pack, int8_unpack)
from cassandra.cqltypes import (AsciiType, BytesType, BooleanType,
CounterColumnType, DateType, DecimalType,
DoubleType, FloatType, Int32Type,
InetAddressType, IntegerType, ListType,
LongType, MapType, SetType, TimeUUIDType,
UTF8Type, UUIDType, lookup_casstype)
log = logging.getLogger(__name__)
class NotSupportedError(Exception):
pass
class InternalError(Exception):
pass
HEADER_DIRECTION_FROM_CLIENT = 0x00
HEADER_DIRECTION_TO_CLIENT = 0x80
HEADER_DIRECTION_MASK = 0x80
_message_types_by_name = {}
_message_types_by_opcode = {}
class _register_msg_type(type):
def __init__(cls, name, bases, dct):
if not name.startswith('_'):
_message_types_by_name[cls.name] = cls
_message_types_by_opcode[cls.opcode] = cls
class _MessageType(object):
__metaclass__ = _register_msg_type
tracing = False
def to_string(self, stream_id, protocol_version, compression=None):
body = StringIO()
self.send_body(body, protocol_version)
body = body.getvalue()
version = protocol_version | HEADER_DIRECTION_FROM_CLIENT
flags = 0
if compression is not None and len(body) > 0:
body = compression(body)
flags |= 0x01
if self.tracing:
flags |= 0x02
msglen = int32_pack(len(body))
msg_parts = map(int8_pack, (version, flags, stream_id, self.opcode)) + [msglen, body]
return ''.join(msg_parts)
def __str__(self):
paramstrs = ['%s=%r' % (pname, getattr(self, pname)) for pname in _get_params(self)]
return '<%s(%s)>' % (self.__class__.__name__, ', '.join(paramstrs))
__repr__ = __str__
def _get_params(message_obj):
base_attrs = dir(_MessageType)
return [a for a in dir(message_obj)
if a not in base_attrs and not a.startswith('_') and not callable(getattr(message_obj, a))]
def decode_response(stream_id, flags, opcode, body, decompressor=None):
if flags & 0x01:
if decompressor is None:
raise Exception("No decompressor available for compressed frame!")
body = decompressor(body)
flags ^= 0x01
body = StringIO(body)
if flags & 0x02:
trace_id = UUID(bytes=body.read(16))
flags ^= 0x02
else:
trace_id = None
if flags:
log.warn("Unknown protocol flags set: %02x. May cause problems.", flags)
msg_class = _message_types_by_opcode[opcode]
msg = msg_class.recv_body(body)
msg.stream_id = stream_id
msg.trace_id = trace_id
return msg
error_classes = {}
class ErrorMessage(_MessageType, Exception):
opcode = 0x00
name = 'ERROR'
summary = 'Unknown'
def __init__(self, code, message, info):
self.code = code
self.message = message
self.info = info
@classmethod
def recv_body(cls, f):
code = read_int(f)
msg = read_string(f)
subcls = error_classes.get(code, cls)
extra_info = subcls.recv_error_info(f)
return subcls(code=code, message=msg, info=extra_info)
def summary_msg(self):
msg = 'code=%04x [%s] message="%s"' \
% (self.code, self.summary, self.message)
if self.info is not None:
msg += (' info=' + repr(self.info))
return msg
def __str__(self):
return '<ErrorMessage %s>' % self.summary_msg()
__repr__ = __str__
@staticmethod
def recv_error_info(f):
pass
def to_exception(self):
return self
class ErrorMessageSubclass(_register_msg_type):
def __init__(cls, name, bases, dct):
if cls.error_code is not None:
error_classes[cls.error_code] = cls
class ErrorMessageSub(ErrorMessage):
__metaclass__ = ErrorMessageSubclass
error_code = None
class RequestExecutionException(ErrorMessageSub):
pass
class RequestValidationException(ErrorMessageSub):
pass
class ServerError(ErrorMessageSub):
summary = 'Server error'
error_code = 0x0000
class ProtocolException(ErrorMessageSub):
summary = 'Protocol error'
error_code = 0x000A
class UnavailableErrorMessage(RequestExecutionException):
summary = 'Unavailable exception'
error_code = 0x1000
@staticmethod
def recv_error_info(f):
return {
'consistency': read_consistency_level(f),
'required_replicas': read_int(f),
'alive_replicas': read_int(f),
}
def to_exception(self):
return Unavailable(self.summary_msg(), **self.info)
class OverloadedErrorMessage(RequestExecutionException):
summary = 'Coordinator node overloaded'
error_code = 0x1001
class IsBootstrappingErrorMessage(RequestExecutionException):
summary = 'Coordinator node is bootstrapping'
error_code = 0x1002
class TruncateError(RequestExecutionException):
summary = 'Error during truncate'
error_code = 0x1003
class WriteTimeoutErrorMessage(RequestExecutionException):
summary = 'Timeout during write request'
error_code = 0x1100
@staticmethod
def recv_error_info(f):
return {
'consistency': read_consistency_level(f),
'received_responses': read_int(f),
'required_responses': read_int(f),
'write_type': read_string(f),
}
def to_exception(self):
return WriteTimeout(self.summary_msg(), **self.info)
class ReadTimeoutErrorMessage(RequestExecutionException):
summary = 'Timeout during read request'
error_code = 0x1200
@staticmethod
def recv_error_info(f):
return {
'consistency': read_consistency_level(f),
'received_responses': read_int(f),
'required_responses': read_int(f),
'data_retrieved': bool(read_byte(f)),
}
def to_exception(self):
return ReadTimeout(self.summary_msg(), **self.info)
class SyntaxException(RequestValidationException):
summary = 'Syntax error in CQL query'
error_code = 0x2000
class UnauthorizedErrorMessage(RequestValidationException):
summary = 'Unauthorized'
error_code = 0x2100
def to_exception(self):
return Unauthorized(self.summary_msg())
class InvalidRequestException(RequestValidationException):
summary = 'Invalid query'
error_code = 0x2200
def to_exception(self):
return InvalidRequest(self.summary_msg())
class ConfigurationException(RequestValidationException):
summary = 'Query invalid because of configuration issue'
error_code = 0x2300
class PreparedQueryNotFound(RequestValidationException):
summary = 'Matching prepared statement not found on this node'
error_code = 0x2500
@staticmethod
def recv_error_info(f):
# return the query ID
return read_binary_string(f)
class AlreadyExistsException(ConfigurationException):
summary = 'Item already exists'
error_code = 0x2400
@staticmethod
def recv_error_info(f):
return {
'keyspace': read_string(f),
'table': read_string(f),
}
def to_exception(self):
return AlreadyExists(**self.info)
class StartupMessage(_MessageType):
opcode = 0x01
name = 'STARTUP'
KNOWN_OPTION_KEYS = set((
'CQL_VERSION',
'COMPRESSION',
))
def __init__(self, cqlversion, options):
self.cqlversion = cqlversion
self.options = options
def send_body(self, f, protocol_version):
optmap = self.options.copy()
optmap['CQL_VERSION'] = self.cqlversion
write_stringmap(f, optmap)
class ReadyMessage(_MessageType):
opcode = 0x02
name = 'READY'
@classmethod
def recv_body(cls, f):
return cls()
class AuthenticateMessage(_MessageType):
opcode = 0x03
name = 'AUTHENTICATE'
def __init__(self, authenticator):
self.authenticator = authenticator
@classmethod
def recv_body(cls, f):
authname = read_string(f)
return cls(authenticator=authname)
class CredentialsMessage(_MessageType):
opcode = 0x04
name = 'CREDENTIALS'
def __init__(self, creds):
self.creds = creds
def send_body(self, f, protocol_version):
if protocol_version > 1:
raise UnsupportedOperation(
"Credentials-based authentication is not supported with "
"protocol version 2 or higher. Use the SASL authentication "
"mechanism instead.")
write_short(f, len(self.creds))
for credkey, credval in self.creds.items():
write_string(f, credkey)
write_string(f, credval)
class OptionsMessage(_MessageType):
opcode = 0x05
name = 'OPTIONS'
def send_body(self, f, protocol_version):
pass
class SupportedMessage(_MessageType):
opcode = 0x06
name = 'SUPPORTED'
def __init__(self, cql_versions, options):
self.cql_versions = cql_versions
self.options = options
@classmethod
def recv_body(cls, f):
options = read_stringmultimap(f)
cql_versions = options.pop('CQL_VERSION')
return cls(cql_versions=cql_versions, options=options)
# used for QueryMessage and ExecuteMessage
_VALUES_FLAG = 0x01
_SKIP_METADATA_FLAG = 0x01
_PAGE_SIZE_FLAG = 0x04
_WITH_PAGING_STATE_FLAG = 0x08
_WITH_SERIAL_CONSISTENCY_FLAG = 0x10
class QueryMessage(_MessageType):
opcode = 0x07
name = 'QUERY'
def __init__(self, query, consistency_level, serial_consistency_level=None,
fetch_size=None, paging_state=None):
self.query = query
self.consistency_level = consistency_level
self.serial_consistency_level = serial_consistency_level
self.fetch_size = fetch_size
self.paging_state = paging_state
def send_body(self, f, protocol_version):
write_longstring(f, self.query)
write_consistency_level(f, self.consistency_level)
flags = 0x00
if self.serial_consistency_level:
if protocol_version >= 2:
flags |= _WITH_SERIAL_CONSISTENCY_FLAG
else:
raise UnsupportedOperation(
"Serial consistency levels require the use of protocol version "
"2 or higher. Consider setting Cluster.protocol_version to 2 "
"to support serial consistency levels.")
if self.fetch_size:
if protocol_version >= 2:
flags |= _PAGE_SIZE_FLAG
else:
raise UnsupportedOperation(
"Automatic query paging may only be used with protocol version "
"2 or higher. Consider setting Cluster.protocol_version to 2.")
if self.paging_state:
if protocol_version >= 2:
flags |= _WITH_PAGING_STATE_FLAG
else:
raise UnsupportedOperation(
"Automatic query paging may only be used with protocol version "
"2 or higher. Consider setting Cluster.protocol_version to 2.")
write_byte(f, flags)
if self.fetch_size:
write_int(f, self.fetch_size)
if self.paging_state:
write_longstring(f, self.paging_state)
if self.serial_consistency_level:
write_consistency_level(f, self.serial_consistency_level)
CUSTOM_TYPE = object()
RESULT_KIND_VOID = 0x0001
RESULT_KIND_ROWS = 0x0002
RESULT_KIND_SET_KEYSPACE = 0x0003
RESULT_KIND_PREPARED = 0x0004
RESULT_KIND_SCHEMA_CHANGE = 0x0005
class ResultMessage(_MessageType):
opcode = 0x08
name = 'RESULT'
kind = None
results = None
paging_state = None
_type_codes = {
0x0000: CUSTOM_TYPE,
0x0001: AsciiType,
0x0002: LongType,
0x0003: BytesType,
0x0004: BooleanType,
0x0005: CounterColumnType,
0x0006: DecimalType,
0x0007: DoubleType,
0x0008: FloatType,
0x0009: Int32Type,
0x000A: UTF8Type,
0x000B: DateType,
0x000C: UUIDType,
0x000D: UTF8Type,
0x000E: IntegerType,
0x000F: TimeUUIDType,
0x0010: InetAddressType,
0x0020: ListType,
0x0021: MapType,
0x0022: SetType,
}
_FLAGS_GLOBAL_TABLES_SPEC = 0x0001
_HAS_MORE_PAGES_FLAG = 0x0002
_NO_METADATA_FLAG = 0x0004
def __init__(self, kind, results, paging_state=None):
self.kind = kind
self.results = results
self.paging_state = paging_state
@classmethod
def recv_body(cls, f):
kind = read_int(f)
paging_state = None
if kind == RESULT_KIND_VOID:
results = None
elif kind == RESULT_KIND_ROWS:
paging_state, results = cls.recv_results_rows(f)
elif kind == RESULT_KIND_SET_KEYSPACE:
ksname = read_string(f)
results = ksname
elif kind == RESULT_KIND_PREPARED:
results = cls.recv_results_prepared(f)
elif kind == RESULT_KIND_SCHEMA_CHANGE:
results = cls.recv_results_schema_change(f)
return cls(kind, results, paging_state)
@classmethod
def recv_results_rows(cls, f):
paging_state, column_metadata = cls.recv_results_metadata(f)
rowcount = read_int(f)
rows = [cls.recv_row(f, len(column_metadata)) for x in xrange(rowcount)]
colnames = [c[2] for c in column_metadata]
coltypes = [c[3] for c in column_metadata]
return (
paging_state,
(colnames, [tuple(ctype.from_binary(val) for ctype, val in zip(coltypes, row))
for row in rows]))
@classmethod
def recv_results_prepared(cls, f):
query_id = read_binary_string(f)
_, column_metadata = cls.recv_results_metadata(f)
return (query_id, column_metadata)
@classmethod
def recv_results_metadata(cls, f):
flags = read_int(f)
glob_tblspec = bool(flags & cls._FLAGS_GLOBAL_TABLES_SPEC)
colcount = read_int(f)
if flags & cls._HAS_MORE_PAGES_FLAG:
paging_state = read_binary_longstring(f)
else:
paging_state = None
if glob_tblspec:
ksname = read_string(f)
cfname = read_string(f)
column_metadata = []
for x in xrange(colcount):
if glob_tblspec:
colksname = ksname
colcfname = cfname
else:
colksname = read_string(f)
colcfname = read_string(f)
colname = read_string(f)
coltype = cls.read_type(f)
column_metadata.append((colksname, colcfname, colname, coltype))
return paging_state, column_metadata
@classmethod
def recv_results_schema_change(cls, f):
change_type = read_string(f)
keyspace = read_string(f)
table = read_string(f)
return dict(change_type=change_type, keyspace=keyspace, table=table)
@classmethod
def read_type(cls, f):
optid = read_short(f)
try:
typeclass = cls._type_codes[optid]
except KeyError:
raise NotSupportedError("Unknown data type code 0x%04x. Have to skip"
" entire result set." % (optid,))
if typeclass in (ListType, SetType):
subtype = cls.read_type(f)
typeclass = typeclass.apply_parameters((subtype,))
elif typeclass == MapType:
keysubtype = cls.read_type(f)
valsubtype = cls.read_type(f)
typeclass = typeclass.apply_parameters((keysubtype, valsubtype))
elif typeclass == CUSTOM_TYPE:
classname = read_string(f)
typeclass = lookup_casstype(classname)
return typeclass
@staticmethod
def recv_row(f, colcount):
return [read_value(f) for x in xrange(colcount)]
class PrepareMessage(_MessageType):
opcode = 0x09
name = 'PREPARE'
def __init__(self, query):
self.query = query
def send_body(self, f, protocol_version):
write_longstring(f, self.query)
class ExecuteMessage(_MessageType):
opcode = 0x0A
name = 'EXECUTE'
def __init__(self, query_id, query_params, consistency_level,
serial_consistency_level=None, fetch_size=None,
paging_state=None):
self.query_id = query_id
self.query_params = query_params
self.consistency_level = consistency_level
self.serial_consistency_level = serial_consistency_level
self.fetch_size = fetch_size
self.paging_state = paging_state
def send_body(self, f, protocol_version):
write_string(f, self.query_id)
if protocol_version == 1:
if self.serial_consistency_level:
raise UnsupportedOperation(
"Serial consistency levels require the use of protocol version "
"2 or higher. Consider setting Cluster.protocol_version to 2 "
"to support serial consistency levels.")
if self.fetch_size or self.paging_state:
raise UnsupportedOperation(
"Automatic query paging may only be used with protocol version "
"2 or higher. Consider setting Cluster.protocol_version to 2.")
write_short(f, len(self.query_params))
for param in self.query_params:
write_value(f, param)
write_consistency_level(f, self.consistency_level)
else:
write_consistency_level(f, self.consistency_level)
flags = _VALUES_FLAG
if self.serial_consistency_level:
flags |= _WITH_SERIAL_CONSISTENCY_FLAG
if self.fetch_size:
flags |= _PAGE_SIZE_FLAG
if self.paging_state:
flags |= _WITH_PAGING_STATE_FLAG
write_byte(f, flags)
write_short(f, len(self.query_params))
for param in self.query_params:
write_value(f, param)
if self.fetch_size:
write_int(f, self.fetch_size)
if self.paging_state:
write_longstring(f, self.paging_state)
if self.serial_consistency_level:
write_consistency_level(f, self.serial_consistency_level)
class BatchMessage(_MessageType):
opcode = 0x0D
name = 'BATCH'
def __init__(self, batch_type, queries, consistency_level):
self.batch_type = batch_type
self.queries = queries
self.consistency_level = consistency_level
def send_body(self, f, protocol_version):
write_byte(f, self.batch_type.value)
write_short(f, len(self.queries))
for prepared, string_or_query_id, params in self.queries:
if not prepared:
write_byte(f, 0)
write_longstring(f, string_or_query_id)
else:
write_byte(f, 1)
write_short(f, len(string_or_query_id))
f.write(string_or_query_id)
write_short(f, len(params))
for param in params:
write_value(f, param)
write_consistency_level(f, self.consistency_level)
known_event_types = frozenset((
'TOPOLOGY_CHANGE',
'STATUS_CHANGE',
'SCHEMA_CHANGE'
))
class RegisterMessage(_MessageType):
opcode = 0x0B
name = 'REGISTER'
def __init__(self, event_list):
self.event_list = event_list
def send_body(self, f, protocol_version):
write_stringlist(f, self.event_list)
class EventMessage(_MessageType):
opcode = 0x0C
name = 'EVENT'
def __init__(self, event_type, event_args):
self.event_type = event_type
self.event_args = event_args
@classmethod
def recv_body(cls, f):
event_type = read_string(f).upper()
if event_type in known_event_types:
read_method = getattr(cls, 'recv_' + event_type.lower())
return cls(event_type=event_type, event_args=read_method(f))
raise NotSupportedError('Unknown event type %r' % event_type)
@classmethod
def recv_topology_change(cls, f):
# "NEW_NODE" or "REMOVED_NODE"
change_type = read_string(f)
address = read_inet(f)
return dict(change_type=change_type, address=address)
@classmethod
def recv_status_change(cls, f):
# "UP" or "DOWN"
change_type = read_string(f)
address = read_inet(f)
return dict(change_type=change_type, address=address)
@classmethod
def recv_schema_change(cls, f):
# "CREATED", "DROPPED", or "UPDATED"
change_type = read_string(f)
keyspace = read_string(f)
table = read_string(f)
return dict(change_type=change_type, keyspace=keyspace, table=table)
def read_byte(f):
return int8_unpack(f.read(1))
def write_byte(f, b):
f.write(int8_pack(b))
def read_int(f):
return int32_unpack(f.read(4))
def write_int(f, i):
f.write(int32_pack(i))
def read_short(f):
return uint16_unpack(f.read(2))
def write_short(f, s):
f.write(uint16_pack(s))
def read_consistency_level(f):
return read_short(f)
def write_consistency_level(f, cl):
write_short(f, cl)
def read_string(f):
size = read_short(f)
contents = f.read(size)
return contents.decode('utf8')
def read_binary_string(f):
size = read_short(f)
contents = f.read(size)
return contents
def write_string(f, s):
if isinstance(s, unicode):
s = s.encode('utf8')
write_short(f, len(s))
f.write(s)
def read_binary_longstring(f):
size = read_int(f)
contents = f.read(size)
return contents
def read_longstring(f):
return read_binary_longstring().decode('utf8')
def write_longstring(f, s):
if isinstance(s, unicode):
s = s.encode('utf8')
write_int(f, len(s))
f.write(s)
def read_stringlist(f):
numstrs = read_short(f)
return [read_string(f) for x in xrange(numstrs)]
def write_stringlist(f, stringlist):
write_short(f, len(stringlist))
for s in stringlist:
write_string(f, s)
def read_stringmap(f):
numpairs = read_short(f)
strmap = {}
for x in xrange(numpairs):
k = read_string(f)
strmap[k] = read_string(f)
return strmap
def write_stringmap(f, strmap):
write_short(f, len(strmap))
for k, v in strmap.items():
write_string(f, k)
write_string(f, v)
def read_stringmultimap(f):
numkeys = read_short(f)
strmmap = {}
for x in xrange(numkeys):
k = read_string(f)
strmmap[k] = read_stringlist(f)
return strmmap
def write_stringmultimap(f, strmmap):
write_short(f, len(strmmap))
for k, v in strmmap.items():
write_string(f, k)
write_stringlist(f, v)
def read_value(f):
size = read_int(f)
if size < 0:
return None
return f.read(size)
def write_value(f, v):
if v is None:
write_int(f, -1)
else:
write_int(f, len(v))
f.write(v)
def read_inet(f):
size = read_byte(f)
addrbytes = f.read(size)
port = read_int(f)
if size == 4:
addrfam = socket.AF_INET
elif size == 16:
addrfam = socket.AF_INET6
else:
raise InternalError("bad inet address: %r" % (addrbytes,))
return (socket.inet_ntop(addrfam, addrbytes), port)
def write_inet(f, addrtuple):
addr, port = addrtuple
if ':' in addr:
addrfam = socket.AF_INET6
else:
addrfam = socket.AF_INET
addrbytes = socket.inet_pton(addrfam, addr)
write_byte(f, len(addrbytes))
f.write(addrbytes)
write_int(f, port)