8bee26d6d6
The root of the problem was that nested data types would use the default encoders for subitems. When the encoders were customized, they would not be used for those nested items. This fix moves the encoder functions into a class so that collections, tuples, and UDTs will use the customized mapping when encoding subitems. Fixes PYTHON-100.
861 lines
30 KiB
Python
861 lines
30 KiB
Python
# Copyright 2013-2014 DataStax, Inc.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""
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This module holds classes for working with prepared statements and
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specifying consistency levels and retry policies for individual
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queries.
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"""
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from collections import namedtuple
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from datetime import datetime, timedelta
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import re
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import struct
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import time
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import six
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from cassandra import ConsistencyLevel, OperationTimedOut
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from cassandra.cqltypes import unix_time_from_uuid1
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from cassandra.encoder import Encoder
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import cassandra.encoder
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from cassandra.util import OrderedDict
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import logging
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log = logging.getLogger(__name__)
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NON_ALPHA_REGEX = re.compile('[^a-zA-Z0-9]')
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START_BADCHAR_REGEX = re.compile('^[^a-zA-Z0-9]*')
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END_BADCHAR_REGEX = re.compile('[^a-zA-Z0-9_]*$')
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_clean_name_cache = {}
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def _clean_column_name(name):
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try:
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return _clean_name_cache[name]
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except KeyError:
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clean = NON_ALPHA_REGEX.sub("_", START_BADCHAR_REGEX.sub("", END_BADCHAR_REGEX.sub("", name)))
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_clean_name_cache[name] = clean
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return clean
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def tuple_factory(colnames, rows):
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"""
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Returns each row as a tuple
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Example::
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>>> from cassandra.query import named_tuple_factory
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>>> session = cluster.connect('mykeyspace')
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>>> session.row_factory = tuple_factory
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>>> rows = session.execute("SELECT name, age FROM users LIMIT 1")
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>>> print rows[0]
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('Bob', 42)
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.. versionchanged:: 2.0.0
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moved from ``cassandra.decoder`` to ``cassandra.query``
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"""
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return rows
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def named_tuple_factory(colnames, rows):
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"""
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Returns each row as a `namedtuple <https://docs.python.org/2/library/collections.html#collections.namedtuple>`_.
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This is the default row factory.
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Example::
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>>> from cassandra.query import named_tuple_factory
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>>> session = cluster.connect('mykeyspace')
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>>> session.row_factory = named_tuple_factory
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>>> rows = session.execute("SELECT name, age FROM users LIMIT 1")
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>>> user = rows[0]
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>>> # you can access field by their name:
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>>> print "name: %s, age: %d" % (user.name, user.age)
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name: Bob, age: 42
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>>> # or you can access fields by their position (like a tuple)
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>>> name, age = user
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>>> print "name: %s, age: %d" % (name, age)
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name: Bob, age: 42
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>>> name = user[0]
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>>> age = user[1]
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>>> print "name: %s, age: %d" % (name, age)
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name: Bob, age: 42
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.. versionchanged:: 2.0.0
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moved from ``cassandra.decoder`` to ``cassandra.query``
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"""
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Row = namedtuple('Row', map(_clean_column_name, colnames))
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return [Row(*row) for row in rows]
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def dict_factory(colnames, rows):
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"""
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Returns each row as a dict.
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Example::
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>>> from cassandra.query import dict_factory
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>>> session = cluster.connect('mykeyspace')
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>>> session.row_factory = dict_factory
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>>> rows = session.execute("SELECT name, age FROM users LIMIT 1")
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>>> print rows[0]
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{u'age': 42, u'name': u'Bob'}
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.. versionchanged:: 2.0.0
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moved from ``cassandra.decoder`` to ``cassandra.query``
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"""
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return [dict(zip(colnames, row)) for row in rows]
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def ordered_dict_factory(colnames, rows):
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"""
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Like :meth:`~cassandra.query.dict_factory`, but returns each row as an OrderedDict,
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so the order of the columns is preserved.
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.. versionchanged:: 2.0.0
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moved from ``cassandra.decoder`` to ``cassandra.query``
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"""
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return [OrderedDict(zip(colnames, row)) for row in rows]
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FETCH_SIZE_UNSET = object()
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class Statement(object):
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"""
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An abstract class representing a single query. There are three subclasses:
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:class:`.SimpleStatement`, :class:`.BoundStatement`, and :class:`.BatchStatement`.
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These can be passed to :meth:`.Session.execute()`.
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"""
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retry_policy = None
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"""
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An instance of a :class:`cassandra.policies.RetryPolicy` or one of its
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subclasses. This controls when a query will be retried and how it
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will be retried.
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"""
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trace = None
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"""
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If :meth:`.Session.execute()` is run with `trace` set to :const:`True`,
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this will be set to a :class:`.QueryTrace` instance.
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"""
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consistency_level = None
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"""
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The :class:`.ConsistencyLevel` to be used for this operation. Defaults
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to :const:`None`, which means that the default consistency level for
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the Session this is executed in will be used.
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"""
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fetch_size = FETCH_SIZE_UNSET
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"""
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How many rows will be fetched at a time. This overrides the default
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of :attr:`.Session.default_fetch_size`
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This only takes effect when protocol version 2 or higher is used.
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See :attr:`.Cluster.protocol_version` for details.
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.. versionadded:: 2.0.0
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"""
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_serial_consistency_level = None
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_routing_key = None
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def __init__(self, retry_policy=None, consistency_level=None, routing_key=None,
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serial_consistency_level=None, fetch_size=FETCH_SIZE_UNSET):
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self.retry_policy = retry_policy
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if consistency_level is not None:
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self.consistency_level = consistency_level
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if serial_consistency_level is not None:
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self.serial_consistency_level = serial_consistency_level
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if fetch_size is not FETCH_SIZE_UNSET:
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self.fetch_size = fetch_size
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self._routing_key = routing_key
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def _get_routing_key(self):
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return self._routing_key
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def _set_routing_key(self, key):
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if isinstance(key, (list, tuple)):
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self._routing_key = b"".join(struct.pack("HsB", len(component), component, 0)
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for component in key)
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else:
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self._routing_key = key
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def _del_routing_key(self):
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self._routing_key = None
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routing_key = property(
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_get_routing_key,
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_set_routing_key,
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_del_routing_key,
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"""
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The :attr:`~.TableMetadata.partition_key` portion of the primary key,
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which can be used to determine which nodes are replicas for the query.
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If the partition key is a composite, a list or tuple must be passed in.
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Each key component should be in its packed (binary) format, so all
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components should be strings.
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""")
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def _get_serial_consistency_level(self):
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return self._serial_consistency_level
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def _set_serial_consistency_level(self, serial_consistency_level):
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acceptable = (None, ConsistencyLevel.SERIAL, ConsistencyLevel.LOCAL_SERIAL)
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if serial_consistency_level not in acceptable:
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raise ValueError(
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"serial_consistency_level must be either ConsistencyLevel.SERIAL "
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"or ConsistencyLevel.LOCAL_SERIAL")
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def _del_serial_consistency_level(self):
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self._serial_consistency_level = None
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serial_consistency_level = property(
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_get_serial_consistency_level,
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_set_serial_consistency_level,
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_del_serial_consistency_level,
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"""
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The serial consistency level is only used by conditional updates
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(``INSERT``, ``UPDATE`` and ``DELETE`` with an ``IF`` condition). For
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those, the ``serial_consistency_level`` defines the consistency level of
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the serial phase (or "paxos" phase) while the normal
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:attr:`~.consistency_level` defines the consistency for the "learn" phase,
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i.e. what type of reads will be guaranteed to see the update right away.
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For example, if a conditional write has a :attr:`~.consistency_level` of
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:attr:`~.ConsistencyLevel.QUORUM` (and is successful), then a
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:attr:`~.ConsistencyLevel.QUORUM` read is guaranteed to see that write.
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But if the regular :attr:`~.consistency_level` of that write is
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:attr:`~.ConsistencyLevel.ANY`, then only a read with a
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:attr:`~.consistency_level` of :attr:`~.ConsistencyLevel.SERIAL` is
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guaranteed to see it (even a read with consistency
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:attr:`~.ConsistencyLevel.ALL` is not guaranteed to be enough).
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The serial consistency can only be one of :attr:`~.ConsistencyLevel.SERIAL`
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or :attr:`~.ConsistencyLevel.LOCAL_SERIAL`. While ``SERIAL`` guarantees full
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linearizability (with other ``SERIAL`` updates), ``LOCAL_SERIAL`` only
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guarantees it in the local data center.
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The serial consistency level is ignored for any query that is not a
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conditional update. Serial reads should use the regular
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:attr:`consistency_level`.
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Serial consistency levels may only be used against Cassandra 2.0+
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and the :attr:`~.Cluster.protocol_version` must be set to 2 or higher.
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.. versionadded:: 2.0.0
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""")
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@property
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def keyspace(self):
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"""
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The string name of the keyspace this query acts on.
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"""
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return None
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class SimpleStatement(Statement):
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"""
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A simple, un-prepared query. All attributes of :class:`Statement` apply
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to this class as well.
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"""
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def __init__(self, query_string, *args, **kwargs):
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"""
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`query_string` should be a literal CQL statement with the exception
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of parameter placeholders that will be filled through the
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`parameters` argument of :meth:`.Session.execute()`.
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"""
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Statement.__init__(self, *args, **kwargs)
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self._query_string = query_string
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@property
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def query_string(self):
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return self._query_string
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def __str__(self):
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consistency = ConsistencyLevel.value_to_name.get(self.consistency_level, 'Not Set')
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return (u'<SimpleStatement query="%s", consistency=%s>' %
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(self.query_string, consistency))
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__repr__ = __str__
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class PreparedStatement(object):
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"""
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A statement that has been prepared against at least one Cassandra node.
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Instances of this class should not be created directly, but through
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:meth:`.Session.prepare()`.
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A :class:`.PreparedStatement` should be prepared only once. Re-preparing a statement
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may affect performance (as the operation requires a network roundtrip).
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"""
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column_metadata = None
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query_id = None
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query_string = None
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keyspace = None
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routing_key_indexes = None
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consistency_level = None
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serial_consistency_level = None
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_protocol_version = None
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fetch_size = FETCH_SIZE_UNSET
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def __init__(self, column_metadata, query_id, routing_key_indexes, query, keyspace,
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protocol_version, consistency_level=None, serial_consistency_level=None,
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fetch_size=FETCH_SIZE_UNSET):
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self.column_metadata = column_metadata
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self.query_id = query_id
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self.routing_key_indexes = routing_key_indexes
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self.query_string = query
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self.keyspace = keyspace
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self._protocol_version = protocol_version
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self.consistency_level = consistency_level
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self.serial_consistency_level = serial_consistency_level
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if fetch_size is not FETCH_SIZE_UNSET:
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self.fetch_size = fetch_size
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@classmethod
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def from_message(cls, query_id, column_metadata, cluster_metadata, query, keyspace, protocol_version):
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if not column_metadata:
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return PreparedStatement(column_metadata, query_id, None, query, keyspace, protocol_version)
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partition_key_columns = None
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routing_key_indexes = None
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ks_name, table_name, _, _ = column_metadata[0]
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ks_meta = cluster_metadata.keyspaces.get(ks_name)
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if ks_meta:
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table_meta = ks_meta.tables.get(table_name)
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if table_meta:
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partition_key_columns = table_meta.partition_key
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# make a map of {column_name: index} for each column in the statement
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statement_indexes = dict((c[2], i) for i, c in enumerate(column_metadata))
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# a list of which indexes in the statement correspond to partition key items
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try:
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routing_key_indexes = [statement_indexes[c.name]
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for c in partition_key_columns]
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except KeyError:
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pass # we're missing a partition key component in the prepared
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# statement; just leave routing_key_indexes as None
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return PreparedStatement(column_metadata, query_id, routing_key_indexes,
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query, keyspace, protocol_version)
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def bind(self, values):
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"""
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Creates and returns a :class:`BoundStatement` instance using `values`.
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The `values` parameter **must** be a sequence, such as a tuple or list,
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even if there is only one value to bind.
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"""
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return BoundStatement(self).bind(values)
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def __str__(self):
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consistency = ConsistencyLevel.value_to_name.get(self.consistency_level, 'Not Set')
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return (u'<PreparedStatement query="%s", consistency=%s>' %
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(self.query_string, consistency))
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__repr__ = __str__
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class BoundStatement(Statement):
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"""
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A prepared statement that has been bound to a particular set of values.
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These may be created directly or through :meth:`.PreparedStatement.bind()`.
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All attributes of :class:`Statement` apply to this class as well.
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"""
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prepared_statement = None
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"""
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The :class:`PreparedStatement` instance that this was created from.
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"""
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values = None
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"""
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The sequence of values that were bound to the prepared statement.
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"""
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def __init__(self, prepared_statement, *args, **kwargs):
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"""
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`prepared_statement` should be an instance of :class:`PreparedStatement`.
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All other ``*args`` and ``**kwargs`` will be passed to :class:`.Statement`.
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"""
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self.consistency_level = prepared_statement.consistency_level
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self.serial_consistency_level = prepared_statement.serial_consistency_level
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self.fetch_size = prepared_statement.fetch_size
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self.prepared_statement = prepared_statement
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self.values = []
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Statement.__init__(self, *args, **kwargs)
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def bind(self, values):
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"""
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Binds a sequence of values for the prepared statement parameters
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and returns this instance. Note that `values` *must* be:
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* a sequence, even if you are only binding one value, or
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* a dict that relates 1-to-1 between dict keys and columns
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"""
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if values is None:
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values = ()
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col_meta = self.prepared_statement.column_metadata
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proto_version = self.prepared_statement._protocol_version
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# special case for binding dicts
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if isinstance(values, dict):
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dict_values = values
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values = []
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# sort values accordingly
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for col in col_meta:
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try:
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values.append(dict_values[col[2]])
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except KeyError:
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raise KeyError(
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'Column name `%s` not found in bound dict.' %
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(col[2]))
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# ensure a 1-to-1 dict keys to columns relationship
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if len(dict_values) != len(col_meta):
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# find expected columns
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columns = set()
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for col in col_meta:
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columns.add(col[2])
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# generate error message
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if len(dict_values) > len(col_meta):
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difference = set(dict_values.keys()).difference(columns)
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msg = "Too many arguments provided to bind() (got %d, expected %d). " + \
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"Unexpected keys %s."
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else:
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difference = set(columns).difference(dict_values.keys())
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msg = "Too few arguments provided to bind() (got %d, expected %d). " + \
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"Expected keys %s."
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# exit with error message
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msg = msg % (len(values), len(col_meta), difference)
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raise ValueError(msg)
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if len(values) > len(col_meta):
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raise ValueError(
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"Too many arguments provided to bind() (got %d, expected %d)" %
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(len(values), len(col_meta)))
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self.raw_values = values
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self.values = []
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for value, col_spec in zip(values, col_meta):
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if value is None:
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self.values.append(None)
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else:
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col_type = col_spec[-1]
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try:
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self.values.append(col_type.serialize(value, proto_version))
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except (TypeError, struct.error):
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col_name = col_spec[2]
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expected_type = col_type
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actual_type = type(value)
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message = ('Received an argument of invalid type for column "%s". '
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'Expected: %s, Got: %s' % (col_name, expected_type, actual_type))
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raise TypeError(message)
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return self
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@property
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def routing_key(self):
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if not self.prepared_statement.routing_key_indexes:
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return None
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if self._routing_key is not None:
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return self._routing_key
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routing_indexes = self.prepared_statement.routing_key_indexes
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if len(routing_indexes) == 1:
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self._routing_key = self.values[routing_indexes[0]]
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else:
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components = []
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for statement_index in routing_indexes:
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val = self.values[statement_index]
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components.append(struct.pack("HsB", len(val), val, 0))
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self._routing_key = b"".join(components)
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return self._routing_key
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@property
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def keyspace(self):
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meta = self.prepared_statement.column_metadata
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if meta:
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return meta[0][0]
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else:
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return None
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|
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def __str__(self):
|
|
consistency = ConsistencyLevel.value_to_name.get(self.consistency_level, 'Not Set')
|
|
return (u'<BoundStatement query="%s", values=%s, consistency=%s>' %
|
|
(self.prepared_statement.query_string, self.raw_values, consistency))
|
|
__repr__ = __str__
|
|
|
|
|
|
class BatchType(object):
|
|
"""
|
|
A BatchType is used with :class:`.BatchStatement` instances to control
|
|
the atomicity of the batch operation.
|
|
|
|
.. versionadded:: 2.0.0
|
|
"""
|
|
|
|
LOGGED = None
|
|
"""
|
|
Atomic batch operation.
|
|
"""
|
|
|
|
UNLOGGED = None
|
|
"""
|
|
Non-atomic batch operation.
|
|
"""
|
|
|
|
COUNTER = None
|
|
"""
|
|
Batches of counter operations.
|
|
"""
|
|
|
|
def __init__(self, name, value):
|
|
self.name = name
|
|
self.value = value
|
|
|
|
def __str__(self):
|
|
return self.name
|
|
|
|
def __repr__(self):
|
|
return "BatchType.%s" % (self.name, )
|
|
|
|
|
|
BatchType.LOGGED = BatchType("LOGGED", 0)
|
|
BatchType.UNLOGGED = BatchType("UNLOGGED", 1)
|
|
BatchType.COUNTER = BatchType("COUNTER", 2)
|
|
|
|
|
|
class BatchStatement(Statement):
|
|
"""
|
|
A protocol-level batch of operations which are applied atomically
|
|
by default.
|
|
|
|
.. versionadded:: 2.0.0
|
|
"""
|
|
|
|
batch_type = None
|
|
"""
|
|
The :class:`.BatchType` for the batch operation. Defaults to
|
|
:attr:`.BatchType.LOGGED`.
|
|
"""
|
|
|
|
_statements_and_parameters = None
|
|
_session = None
|
|
|
|
def __init__(self, batch_type=BatchType.LOGGED, retry_policy=None,
|
|
consistency_level=None, session=None):
|
|
"""
|
|
`batch_type` specifies The :class:`.BatchType` for the batch operation.
|
|
Defaults to :attr:`.BatchType.LOGGED`.
|
|
|
|
`retry_policy` should be a :class:`~.RetryPolicy` instance for
|
|
controlling retries on the operation.
|
|
|
|
`consistency_level` should be a :class:`~.ConsistencyLevel` value
|
|
to be used for all operations in the batch.
|
|
|
|
Example usage:
|
|
|
|
.. code-block:: python
|
|
|
|
insert_user = session.prepare("INSERT INTO users (name, age) VALUES (?, ?)")
|
|
batch = BatchStatement(consistency_level=ConsistencyLevel.QUORUM)
|
|
|
|
for (name, age) in users_to_insert:
|
|
batch.add(insert_user, (name, age))
|
|
|
|
session.execute(batch)
|
|
|
|
You can also mix different types of operations within a batch:
|
|
|
|
.. code-block:: python
|
|
|
|
batch = BatchStatement()
|
|
batch.add(SimpleStatement("INSERT INTO users (name, age) VALUES (%s, %s)", (name, age))
|
|
batch.add(SimpleStatement("DELETE FROM pending_users WHERE name=%s", (name,))
|
|
session.execute(batch)
|
|
|
|
.. versionadded:: 2.0.0
|
|
"""
|
|
self.batch_type = batch_type
|
|
self._statements_and_parameters = []
|
|
self._session = session
|
|
Statement.__init__(self, retry_policy=retry_policy, consistency_level=consistency_level)
|
|
|
|
def add(self, statement, parameters=None):
|
|
"""
|
|
Adds a :class:`.Statement` and optional sequence of parameters
|
|
to be used with the statement to the batch.
|
|
|
|
Like with other statements, parameters must be a sequence, even
|
|
if there is only one item.
|
|
"""
|
|
if isinstance(statement, six.string_types):
|
|
if parameters:
|
|
encoder = Encoder() if self._session is None else self._session.encoder
|
|
statement = bind_params(statement, parameters, encoder)
|
|
self._statements_and_parameters.append((False, statement, ()))
|
|
elif isinstance(statement, PreparedStatement):
|
|
query_id = statement.query_id
|
|
bound_statement = statement.bind(() if parameters is None else parameters)
|
|
self._statements_and_parameters.append(
|
|
(True, query_id, bound_statement.values))
|
|
elif isinstance(statement, BoundStatement):
|
|
if parameters:
|
|
raise ValueError(
|
|
"Parameters cannot be passed with a BoundStatement "
|
|
"to BatchStatement.add()")
|
|
self._statements_and_parameters.append(
|
|
(True, statement.prepared_statement.query_id, statement.values))
|
|
else:
|
|
# it must be a SimpleStatement
|
|
query_string = statement.query_string
|
|
if parameters:
|
|
encoder = Encoder() if self._session is None else self._session.encoder
|
|
query_string = bind_params(query_string, parameters, encoder)
|
|
self._statements_and_parameters.append((False, query_string, ()))
|
|
return self
|
|
|
|
def add_all(self, statements, parameters):
|
|
"""
|
|
Adds a sequence of :class:`.Statement` objects and a matching sequence
|
|
of parameters to the batch. :const:`None` can be used in place of
|
|
parameters when no parameters are needed.
|
|
"""
|
|
for statement, value in zip(statements, parameters):
|
|
self.add(statement, parameters)
|
|
|
|
def __str__(self):
|
|
consistency = ConsistencyLevel.value_to_name.get(self.consistency_level, 'Not Set')
|
|
return (u'<BatchStatement type=%s, statements=%d, consistency=%s>' %
|
|
(self.batch_type, len(self._statements_and_parameters), consistency))
|
|
__repr__ = __str__
|
|
|
|
|
|
ValueSequence = cassandra.encoder.ValueSequence
|
|
"""
|
|
A wrapper class that is used to specify that a sequence of values should
|
|
be treated as a CQL list of values instead of a single column collection when used
|
|
as part of the `parameters` argument for :meth:`.Session.execute()`.
|
|
|
|
This is typically needed when supplying a list of keys to select.
|
|
For example::
|
|
|
|
>>> my_user_ids = ('alice', 'bob', 'charles')
|
|
>>> query = "SELECT * FROM users WHERE user_id IN %s"
|
|
>>> session.execute(query, parameters=[ValueSequence(my_user_ids)])
|
|
|
|
"""
|
|
|
|
|
|
def bind_params(query, params, encoder):
|
|
if isinstance(params, dict):
|
|
return query % dict((k, encoder.cql_encode_all_types(v)) for k, v in six.iteritems(params))
|
|
else:
|
|
return query % tuple(encoder.cql_encode_all_types(v) for v in params)
|
|
|
|
|
|
class TraceUnavailable(Exception):
|
|
"""
|
|
Raised when complete trace details cannot be fetched from Cassandra.
|
|
"""
|
|
pass
|
|
|
|
|
|
class QueryTrace(object):
|
|
"""
|
|
A trace of the duration and events that occurred when executing
|
|
an operation.
|
|
"""
|
|
|
|
trace_id = None
|
|
"""
|
|
:class:`uuid.UUID` unique identifier for this tracing session. Matches
|
|
the ``session_id`` column in ``system_traces.sessions`` and
|
|
``system_traces.events``.
|
|
"""
|
|
|
|
request_type = None
|
|
"""
|
|
A string that very generally describes the traced operation.
|
|
"""
|
|
|
|
duration = None
|
|
"""
|
|
A :class:`datetime.timedelta` measure of the duration of the query.
|
|
"""
|
|
|
|
coordinator = None
|
|
"""
|
|
The IP address of the host that acted as coordinator for this request.
|
|
"""
|
|
|
|
parameters = None
|
|
"""
|
|
A :class:`dict` of parameters for the traced operation, such as the
|
|
specific query string.
|
|
"""
|
|
|
|
started_at = None
|
|
"""
|
|
A UTC :class:`datetime.datetime` object describing when the operation
|
|
was started.
|
|
"""
|
|
|
|
events = None
|
|
"""
|
|
A chronologically sorted list of :class:`.TraceEvent` instances
|
|
representing the steps the traced operation went through. This
|
|
corresponds to the rows in ``system_traces.events`` for this tracing
|
|
session.
|
|
"""
|
|
|
|
_session = None
|
|
|
|
_SELECT_SESSIONS_FORMAT = "SELECT * FROM system_traces.sessions WHERE session_id = %s"
|
|
_SELECT_EVENTS_FORMAT = "SELECT * FROM system_traces.events WHERE session_id = %s"
|
|
_BASE_RETRY_SLEEP = 0.003
|
|
|
|
def __init__(self, trace_id, session):
|
|
self.trace_id = trace_id
|
|
self._session = session
|
|
|
|
def populate(self, max_wait=2.0):
|
|
"""
|
|
Retrieves the actual tracing details from Cassandra and populates the
|
|
attributes of this instance. Because tracing details are stored
|
|
asynchronously by Cassandra, this may need to retry the session
|
|
detail fetch. If the trace is still not available after `max_wait`
|
|
seconds, :exc:`.TraceUnavailable` will be raised; if `max_wait` is
|
|
:const:`None`, this will retry forever.
|
|
"""
|
|
attempt = 0
|
|
start = time.time()
|
|
while True:
|
|
time_spent = time.time() - start
|
|
if max_wait is not None and time_spent >= max_wait:
|
|
raise TraceUnavailable(
|
|
"Trace information was not available within %f seconds. Consider raising Session.max_trace_wait." % (max_wait,))
|
|
|
|
log.debug("Attempting to fetch trace info for trace ID: %s", self.trace_id)
|
|
session_results = self._execute(
|
|
self._SELECT_SESSIONS_FORMAT, (self.trace_id,), time_spent, max_wait)
|
|
|
|
if not session_results or session_results[0].duration is None:
|
|
time.sleep(self._BASE_RETRY_SLEEP * (2 ** attempt))
|
|
attempt += 1
|
|
continue
|
|
log.debug("Fetched trace info for trace ID: %s", self.trace_id)
|
|
|
|
session_row = session_results[0]
|
|
self.request_type = session_row.request
|
|
self.duration = timedelta(microseconds=session_row.duration)
|
|
self.started_at = session_row.started_at
|
|
self.coordinator = session_row.coordinator
|
|
self.parameters = session_row.parameters
|
|
|
|
log.debug("Attempting to fetch trace events for trace ID: %s", self.trace_id)
|
|
time_spent = time.time() - start
|
|
event_results = self._execute(
|
|
self._SELECT_EVENTS_FORMAT, (self.trace_id,), time_spent, max_wait)
|
|
log.debug("Fetched trace events for trace ID: %s", self.trace_id)
|
|
self.events = tuple(TraceEvent(r.activity, r.event_id, r.source, r.source_elapsed, r.thread)
|
|
for r in event_results)
|
|
break
|
|
|
|
def _execute(self, query, parameters, time_spent, max_wait):
|
|
# in case the user switched the row factory, set it to namedtuple for this query
|
|
future = self._session._create_response_future(query, parameters, trace=False)
|
|
future.row_factory = named_tuple_factory
|
|
future.send_request()
|
|
|
|
timeout = (max_wait - time_spent) if max_wait is not None else None
|
|
try:
|
|
return future.result(timeout=timeout)
|
|
except OperationTimedOut:
|
|
raise TraceUnavailable("Trace information was not available within %f seconds" % (max_wait,))
|
|
|
|
def __str__(self):
|
|
return "%s [%s] coordinator: %s, started at: %s, duration: %s, parameters: %s" \
|
|
% (self.request_type, self.trace_id, self.coordinator, self.started_at,
|
|
self.duration, self.parameters)
|
|
|
|
|
|
class TraceEvent(object):
|
|
"""
|
|
Representation of a single event within a query trace.
|
|
"""
|
|
|
|
description = None
|
|
"""
|
|
A brief description of the event.
|
|
"""
|
|
|
|
datetime = None
|
|
"""
|
|
A UTC :class:`datetime.datetime` marking when the event occurred.
|
|
"""
|
|
|
|
source = None
|
|
"""
|
|
The IP address of the node this event occurred on.
|
|
"""
|
|
|
|
source_elapsed = None
|
|
"""
|
|
A :class:`datetime.timedelta` measuring the amount of time until
|
|
this event occurred starting from when :attr:`.source` first
|
|
received the query.
|
|
"""
|
|
|
|
thread_name = None
|
|
"""
|
|
The name of the thread that this event occurred on.
|
|
"""
|
|
|
|
def __init__(self, description, timeuuid, source, source_elapsed, thread_name):
|
|
self.description = description
|
|
self.datetime = datetime.utcfromtimestamp(unix_time_from_uuid1(timeuuid))
|
|
self.source = source
|
|
if source_elapsed is not None:
|
|
self.source_elapsed = timedelta(microseconds=source_elapsed)
|
|
else:
|
|
self.source_elapsed = None
|
|
self.thread_name = thread_name
|
|
|
|
def __str__(self):
|
|
return "%s on %s[%s] at %s" % (self.description, self.source, self.thread_name, self.datetime)
|