272 lines
8.6 KiB
Python
272 lines
8.6 KiB
Python
# Copyright (c) 2014 Rackspace, 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.
|
|
|
|
"""Cassandra storage driver implementation."""
|
|
|
|
import copy
|
|
import multiprocessing
|
|
import os
|
|
import ssl
|
|
|
|
import cassandra
|
|
from cassandra import auth
|
|
from cassandra import cluster
|
|
from cassandra import policies
|
|
from cassandra import query
|
|
from cdeploy import migrator
|
|
from oslo_config import cfg
|
|
from oslo_log import log
|
|
|
|
from poppy.storage import base
|
|
from poppy.storage.cassandra import controllers
|
|
|
|
|
|
LOG = log.getLogger(__name__)
|
|
|
|
CASSANDRA_OPTIONS = [
|
|
cfg.ListOpt('cluster', default=['127.0.0.1'],
|
|
help='Cassandra cluster contact points'),
|
|
cfg.IntOpt('port', default=9042, help='Cassandra cluster port'),
|
|
cfg.BoolOpt('ssl_enabled', default=False,
|
|
help='Communicate with Cassandra over SSL?'),
|
|
cfg.StrOpt('ssl_ca_certs', default='',
|
|
help='Absolute path to the appropriate .crt file'),
|
|
cfg.BoolOpt('auth_enabled', default=False,
|
|
help='Does Cassandra have authentication enabled?'),
|
|
cfg.StrOpt('username', default='', help='Cassandra username'),
|
|
cfg.StrOpt('password', default='', help='Cassandra password'),
|
|
cfg.StrOpt('load_balance_strategy', default='RoundRobinPolicy',
|
|
help='Load balancing strategy for connecting to cluster nodes'),
|
|
cfg.StrOpt('consistency_level', default='ONE',
|
|
help='Consistency level of your cassandra query'),
|
|
cfg.StrOpt('migrations_consistency_level', default='LOCAL_QUORUM',
|
|
help='Consistency level of cassandra migration queries'),
|
|
cfg.IntOpt('max_schema_agreement_wait', default=10,
|
|
help='The maximum duration (in seconds) that the driver will'
|
|
' wait for schema agreement across the cluster.'),
|
|
cfg.StrOpt('keyspace', default='poppy',
|
|
help='Keyspace for all queries made in session'),
|
|
cfg.DictOpt(
|
|
'replication_strategy',
|
|
default={
|
|
'class': 'SimpleStrategy',
|
|
'replication_factor': '1'
|
|
},
|
|
help='Replication strategy for Cassandra cluster'
|
|
),
|
|
cfg.StrOpt(
|
|
'migrations_path',
|
|
default=os.path.join(os.path.dirname(__file__), 'migrations'),
|
|
help='Path to directory containing CQL migration scripts',
|
|
),
|
|
cfg.BoolOpt('archive_on_delete', default=True,
|
|
help='Archive services on delete?'),
|
|
cfg.BoolOpt('automatic_schema_migration', default=False,
|
|
help='Automatically migrate schema in request ?')
|
|
]
|
|
|
|
CASSANDRA_GROUP = 'drivers:storage:cassandra'
|
|
|
|
|
|
def _connection(conf, datacenter, keyspace=None):
|
|
"""connection.
|
|
|
|
:param datacenter
|
|
:returns session
|
|
"""
|
|
ssl_options = None
|
|
if conf.ssl_enabled:
|
|
ssl_options = {
|
|
'ca_certs': conf.ssl_ca_certs,
|
|
'ssl_version': ssl.PROTOCOL_TLSv1
|
|
}
|
|
|
|
auth_provider = None
|
|
if conf.auth_enabled:
|
|
auth_provider = auth.PlainTextAuthProvider(
|
|
username=conf.username,
|
|
password=conf.password
|
|
)
|
|
|
|
load_balancing_policy_class = getattr(policies, conf.load_balance_strategy)
|
|
if load_balancing_policy_class is policies.DCAwareRoundRobinPolicy:
|
|
load_balancing_policy = load_balancing_policy_class(datacenter)
|
|
else:
|
|
load_balancing_policy = load_balancing_policy_class()
|
|
|
|
cluster_connection = cluster.Cluster(
|
|
conf.cluster,
|
|
auth_provider=auth_provider,
|
|
load_balancing_policy=load_balancing_policy,
|
|
port=conf.port,
|
|
ssl_options=ssl_options,
|
|
max_schema_agreement_wait=conf.max_schema_agreement_wait
|
|
)
|
|
|
|
session = cluster_connection.connect()
|
|
if not keyspace:
|
|
keyspace = conf.keyspace
|
|
try:
|
|
session.set_keyspace(keyspace)
|
|
except cassandra.InvalidRequest:
|
|
_create_keyspace(session, keyspace, conf.replication_strategy)
|
|
|
|
if conf.automatic_schema_migration:
|
|
migration_session = copy.copy(session)
|
|
migration_session.default_consistency_level = \
|
|
getattr(cassandra.ConsistencyLevel,
|
|
conf.migrations_consistency_level)
|
|
_run_migrations(conf.migrations_path, migration_session)
|
|
|
|
session.row_factory = query.dict_factory
|
|
|
|
return session
|
|
|
|
|
|
def _create_keyspace(session, keyspace, replication_strategy):
|
|
"""create_keyspace.
|
|
|
|
:param keyspace
|
|
:param replication_strategy
|
|
"""
|
|
LOG.debug('Creating keyspace: ' + keyspace)
|
|
|
|
# replication factor will come in as a string with quotes already
|
|
session.execute(
|
|
"CREATE KEYSPACE " + keyspace + " " +
|
|
"WITH REPLICATION = " + str(replication_strategy) + ";"
|
|
)
|
|
session.set_keyspace(keyspace)
|
|
|
|
|
|
def _run_migrations(migrations_path, session):
|
|
LOG.debug('Running schema migration(s)')
|
|
|
|
schema_migrator = migrator.Migrator(migrations_path, session)
|
|
schema_migrator.run_migrations()
|
|
|
|
|
|
class CassandraStorageDriver(base.Driver):
|
|
"""Cassandra Storage Driver."""
|
|
|
|
def __init__(self, conf):
|
|
super(CassandraStorageDriver, self).__init__(conf)
|
|
conf.register_opts(CASSANDRA_OPTIONS, group=CASSANDRA_GROUP)
|
|
self.cassandra_conf = conf[CASSANDRA_GROUP]
|
|
self.datacenter = conf.datacenter
|
|
self.consistency_level = getattr(
|
|
cassandra.ConsistencyLevel,
|
|
conf[CASSANDRA_GROUP].consistency_level)
|
|
self.session = None
|
|
self.archive_on_delete = self.cassandra_conf.archive_on_delete
|
|
self.lock = multiprocessing.Lock()
|
|
|
|
def change_namespace(self, namespace):
|
|
"""change_namespace.
|
|
|
|
:param namespace
|
|
"""
|
|
self.cassandra_conf.keyspace = namespace
|
|
|
|
def delete_namespace(self, namespace):
|
|
"""delete_namespace.
|
|
|
|
:param namespace
|
|
"""
|
|
self.connection.execute('DROP KEYSPACE ' + namespace)
|
|
|
|
def is_alive(self):
|
|
"""Health check for Cassandra."""
|
|
|
|
try:
|
|
self.database.execute(
|
|
"SELECT cluster_name, data_center FROM system.local;")
|
|
except Exception:
|
|
return False
|
|
return True
|
|
|
|
@property
|
|
def storage_name(self):
|
|
"""storage name.
|
|
|
|
:returns 'Cassandra'
|
|
"""
|
|
return 'Cassandra'
|
|
|
|
@property
|
|
def connection(self):
|
|
"""Cassandra connection instance."""
|
|
return _connection(self.cassandra_conf, self.datacenter)
|
|
|
|
@property
|
|
def services_controller(self):
|
|
"""services_controller.
|
|
|
|
:returns service controller
|
|
"""
|
|
return controllers.ServicesController(self)
|
|
|
|
@property
|
|
def flavors_controller(self):
|
|
"""flavors_controller.
|
|
|
|
:returns flavor controller
|
|
"""
|
|
return controllers.FlavorsController(self)
|
|
|
|
@property
|
|
def database(self):
|
|
"""database.
|
|
|
|
:returns session
|
|
"""
|
|
# if the session has been shutdown, reopen a session
|
|
# Add a time out when acquiring lock to avoid deadlock
|
|
# typically the lock acquiring will not hit timeout,
|
|
# in the case of massive database connection in a short
|
|
# amount of time, timeout can help avoid deadlock and
|
|
# can keep system running fine
|
|
# see https://docs.python.org/2/library/multiprocessing.html#
|
|
# synchronization-primitives for more details
|
|
lock_success = False
|
|
try:
|
|
if self.session is None or self.session.is_shutdown:
|
|
# only require lock when the session is closed
|
|
lock_success = self.lock.acquire(block=True, timeout=10)
|
|
self.connect()
|
|
finally:
|
|
if lock_success:
|
|
self.lock.release()
|
|
return self.session
|
|
|
|
def connect(self):
|
|
"""connect.
|
|
|
|
:returns connection
|
|
"""
|
|
self.session = _connection(self.cassandra_conf, self.datacenter)
|
|
|
|
def close_connection(self):
|
|
"""close_connection."""
|
|
lock_success = False
|
|
try:
|
|
lock_success = self.lock.acquire(block=True, timeout=10)
|
|
self.session.cluster.shutdown()
|
|
self.session.shutdown()
|
|
self.session = None
|
|
finally:
|
|
if lock_success:
|
|
self.lock.release()
|